U.S. patent application number 14/543643 was filed with the patent office on 2015-03-12 for integration of a computer-based message priority system with mobile electronic devices.
The applicant listed for this patent is Microsoft Corporation. Invention is credited to Eric J. Horvitz.
Application Number | 20150072709 14/543643 |
Document ID | / |
Family ID | 31993816 |
Filed Date | 2015-03-12 |
United States Patent
Application |
20150072709 |
Kind Code |
A1 |
Horvitz; Eric J. |
March 12, 2015 |
INTEGRATION OF A COMPUTER-BASED MESSAGE PRIORITY SYSTEM WITH MOBILE
ELECTRONIC DEVICES
Abstract
Methods for integrating mobile electronic devices with
computational methods for assigning priorities to documents are
disclosed. In one embodiment, a computer-implemented method first
receives a new document such as an electronic mail message. The
method assigns a priority to the document, based on a text
classifier such as a Bayesian classifier or a support-vector
machine classifier. The method then alerts a user on an electronic
device, such as a pager or a cellular phone, based on an alert
criteria that can be made sensitive to information about the
location, inferred task, and focus of attention of the user. Such
information can be inferred under uncertainty or can be accessed
directly from online information sources. One embodiment makes use
of information from an online calendar to control the criteria used
to make decisions about relaying information to a mobile
device.
Inventors: |
Horvitz; Eric J.; (Kirkland,
WA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Microsoft Corporation |
Redmond |
WA |
US |
|
|
Family ID: |
31993816 |
Appl. No.: |
14/543643 |
Filed: |
November 17, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12258749 |
Oct 27, 2008 |
8892674 |
|
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14543643 |
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10795695 |
Mar 8, 2004 |
7444384 |
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12258749 |
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09365293 |
Jul 30, 1999 |
6714967 |
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10795695 |
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Current U.S.
Class: |
455/456.1 ;
709/206 |
Current CPC
Class: |
G06Q 10/107 20130101;
H04W 4/025 20130101; H04L 51/34 20130101; H04L 51/24 20130101; H04W
4/12 20130101; H04L 51/26 20130101; H04L 51/12 20130101 |
Class at
Publication: |
455/456.1 ;
709/206 |
International
Class: |
H04L 12/58 20060101
H04L012/58; H04W 4/02 20060101 H04W004/02; H04W 4/12 20060101
H04W004/12 |
Claims
1. A method in a first device, comprising: receiving a text
directed to a user; generating a priority of the text; and
contacting a second device over a network to alert the user based
on an alert criteria.
2. The method of claim 1, wherein said contacting comprises:
contacting the second device over the network to alert the user
based on the alert criteria, the second device being a mobile
device.
3. The method of claim 2, further comprising: using information
from an online calendar in a decision regarding relaying alert
information to the mobile device.
4. The method of claim 1, further comprising: assessing a location
of the user as at least a portion of the alert criteria.
5. The method of claim 1, further comprising: inferring a current
task of the user as at least a portion of the alert criteria.
6. The method of claim 1, further comprising: inferring a focus of
attention of the user as at least a portion of the alert
criteria.
7. The method of claim 1, wherein said contacting comprises:
contacting the second device over the network to alert the user
based on the alert criteria, the second device being a device that
is worn by the user.
8. An electronic device, comprising: a processing unit; and system
memory that stores at least one program configured to be executed
by the processing unit to: generate a priority of a received text
that is directed to a user; determine an expected cost of alerting
the user regarding the received text based at least on a sensor
associated with the user; and alert the user.
9. The electronic device of claim 8, wherein the sensor is at least
one of an infrared sensor or a pressure sensor.
10. The electronic device of claim 8, wherein the sensor is on the
user.
11. The electronic device of claim 8, wherein the at least one
program is configured to be executed by the processing unit to
alert the user when the determined expected cost of alerting the
user is not greater than an expected cost of distracting the
user.
12. The electronic device of claim 8, wherein to determine the
expected cost of alerting the user, the at least one program is
configured to be executed by the processing unit at least to infer
an activity of the user.
13. The electronic device of claim 8, wherein to infer the activity
of the user, the at least one program is configured to be executed
by the processing unit to at least one of: perform automated scene
analysis; determine last mouse or keyboard activity; perform
acoustical analysis; determine recent application history;
determine an application in focus; determine a telephone status; or
analyze explicit user input about whereabouts.
14. A server, comprising: a processing unit; a network interface;
and system memory that stores at least one program configured to be
executed by the processing unit to: receive a text directed to a
user; generate a priority of the text; and operate the network
interface to communicate with an electronic device over a network
to alert the user based on an alert criteria.
15. The server of claim 14, wherein the electronic device is a
mobile device.
16. The server of claim 14, wherein the at least one program is
configured to be executed by the processing unit to: use
information from an online calendar in a decision regarding
relaying alert information to the electronic device.
17. The server of claim 14, wherein the at least one program is
configured to be executed by the processing unit to: assess a
location of the user as at least a portion of the alert
criteria.
18. The server of claim 14, wherein the at least one program is
configured to be executed by the processing unit to: infer a
current task of the user as at least a portion of the alert
criteria.
19. The server of claim 14, wherein the at least one program is
configured to be executed by the processing unit to: infer a focus
of attention of the user as at least a portion of the alert
criteria.
20. The server of claim 14, wherein the electronic device is worn
by the user.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. Ser. No.
12/258,749, filed Oct. 27, 2008, entitled "Integration of a
Computer-Based Message Priority System With Mobile Electronic
Devices", now allowed, which is a continuation of U.S. Ser. No.
10/795,695, filed Mar. 8, 2004, entitled "Integration of a
Computer-Based Message Priority System With Mobile Electronic
Devices", now U.S. Pat. No. 7,444,384, which is a continuation of
Ser. No. 09/365,293, filed on Jul. 30, 1999, entitled "Integration
of a Computer-Based Message Priority System With Mobile Electronic
Devices", now U.S. Pat. No. 6,714,967, which is related to the
cofiled, copending and coassigned applications entitled "Method for
Automatically Assigning Priorities to Documents and Messages",
filed on Jul. 30, 1999 and assigned Ser. No. 09/364,527, now U.S.
Pat. No. 7,194,681, "Methods for Routing Documents based on a
Measure of Criticality", filed on Jul. 30, 1999 and assigned Ser.
No. 09/364,528, now U.S. Pat. No. 6,622,160, "Methods for Display,
Notification, and Interaction with Prioritized Messages", filed on
Jul. 30, 1999, and assigned Ser. No. 09/364,522, now U.S. Pat. No.
7,120,865, and "A Computational Architecture for Managing the
Transmittal and Rendering of Information, Alerts, and
Notifications", filed on Jul. 30, 1999 and assigned Ser. No.
09/365,287, now U.S. Pat. No. 6,618,716, the entireties of all of
which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to prioritized text such as
prioritized email messages, and more particularly to electronic
device alerting for such prioritized text.
BACKGROUND OF THE INVENTION
[0003] Electronic mail programs have become a popular application
among computer users. Especially with the advent of the Internet,
exchanging email has almost become a reason why people purchase
computers for personal reasons, and within many corporate
environments, email has become the standard manner by which
coworkers exchange information. However, with the increasing
popularity of email, shortcomings have become apparent.
[0004] Chief among these shortcomings is that many users now face a
deluge of email every day, such that the capability of being able
to send and receive email has almost become a hindrance to their
day-to-day ability to get their job done, as opposed to being an
asset. Some users report receiving over 100 email messages a day.
With such large numbers of email, it is difficult to manage the
email, such that the users read the most important messages
first.
[0005] Limited solutions to this problem have been attempted in the
prior art. Prior art exists for attempting to curtail the amount of
junk email--e.g., unsolicited email, typically regarding a service
or product for sale--that users receive. Moreover, some electronic
mail programs allow for the generation of rules that govern how an
email is managed within the program--for example, placing all
emails from certain coworkers in a special folder.
[0006] These limited solutions, however, do not strike at the basic
problem behind email--that with so much email being received, it
would be most useful for a user to be able to have his or her
computer automatically prioritize the email by importance or review
urgency, and perform actions based on that prioritization. For
these and other reasons, there is a need for the present
invention.
SUMMARY OF THE INVENTION
[0007] The invention relates to electronic device alerting for
prioritized text. In one embodiment, a computer-implemented method
first receives a text. The method generates a priority of the text,
based on a text classifier such as a Bayesian classifier or a
support-vector machine classifier. The method then alerts a user on
an electronic device, such as a pager or a cellular phone, based on
an alert criteria.
[0008] Embodiments of the invention provide for advantages over the
prior art. A user, for example, in one embodiment, may ask that he
or she only be disturbed if the priority of the text is greater
than a given threshold. Thus, even if the user receives over 100
different email, he or she will be alerted to the most important
email, and then will be able to deal with the other email when the
user has time. Prioritization, in other words, makes email much
more useful in environments where a lot of email is exchanged on a
regular basis.
[0009] Embodiments of the invention include computer-implemented
methods, computer-readable media, and computerized systems of
varying embodiments. Still other embodiments, advantages and
aspects of the invention will become apparent by reading the
following detailed description, and by reference to the
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a diagram of an operating environment in
conjunction with which embodiments of the invention may be
practiced;
[0011] FIG. 2 is a diagram showing explicit and implicit training
of a text classifier, according to an embodiment of the
invention;
[0012] FIG. 3 is a diagram showing how a priority for a text is
generated by input to a text classifier, according to an embodiment
of the invention;
[0013] FIG. 4(a) is a diagram of a scheme according to which the
priority of a text can be classified, according to an embodiment of
the invention;
[0014] FIG. 4(b) is a diagram of another scheme according to which
the priority of a text can be classified, according to another
embodiment of the invention;
[0015] FIG. 5(a) is a graph showing linear cost functions of high,
medium and low priority texts, according to an embodiment of the
invention;
[0016] FIG. 5(b) is a graph showing a non-linear cost function for
a text, according to an embodiment of the invention;
[0017] FIG. 6 is a diagram showing classes of evidence that can be
used to make an inference about a user's activity (e.g., if a user
is present), according to one embodiment of the invention;
[0018] FIG. 7 is a diagram showing a Bayesian network that can be
used for inferring a user's activity (e.g., if a user is present),
according to one embodiment of the invention;
[0019] FIGS. 8-10 are influence diagrams showing how in one
embodiment decision models can be utilized to make the decision as
to how and when to alert a user to a message;
[0020] FIG. 11 is a flowchart of a method according to an
embodiment of the invention;
[0021] FIG. 12 is a diagram of a system according to an embodiment
of the invention;
[0022] FIG. 13 is a diagram of a system according to another
embodiment of the invention; and,
[0023] FIG. 14 is a diagram of a user interface via which alert
criteria can be modified, according to an embodiment of the
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0024] In the following detailed description of exemplary
embodiments of the invention, reference is made to the accompanying
drawings which form a part hereof, and in which is shown by way of
illustration specific exemplary embodiments in which the invention
may be practiced. These embodiments are described in sufficient
detail to enable those skilled in the art to practice the
invention, and it is to be understood that other embodiments may be
utilized and that logical, mechanical, electrical and other changes
may be made without departing from the spirit or scope of the
present invention. The following detailed description is,
therefore, not to be taken in a limiting sense, and the scope of
the present invention is defined only by the appended claims.
[0025] Some portions of the detailed descriptions which follow are
presented in terms of algorithms and symbolic representations of
operations on data bits within a computer memory. These algorithmic
descriptions and representations are the means used by those
skilled in the data processing arts to most effectively convey the
substance of their work to others skilled in the art. An algorithm
is here, and generally, conceived to be a self-consistent sequence
of steps leading to a desired result. The steps are those requiring
physical manipulations of physical quantities. Usually, though not
necessarily, these quantities take the form of electrical or
magnetic signals capable of being stored, transferred, combined,
compared, and otherwise manipulated.
[0026] It has proven convenient at times, principally for reasons
of common usage, to refer to these signals as bits, values,
elements, symbols, characters, terms, numbers, or the like. It
should be borne in mind, however, that all of these and similar
terms are to be associated with the appropriate physical quantities
and are merely convenient labels applied to these quantities.
Unless specifically stated otherwise as apparent from the following
discussions, it is appreciated that throughout the present
invention, discussions utilizing terms such as processing or
computing or calculating or determining or displaying or the like,
refer to the action and processes of a computer system, or similar
electronic computing device, that manipulates and transforms data
represented as physical (electronic) quantities within the computer
system's registers and memories into other data similarly
represented as physical quantities within the computer system
memories or registers or other such information storage,
transmission or display devices. (It is noted that the terms
document and text are used interchangeably herein and should be
construed as interchangeable as well.)
Operating Environment
[0027] Referring to FIG. 1, a diagram of the hardware and operating
environment in conjunction with which embodiments of the invention
may be practiced is shown. The description of FIG. 1 is intended to
provide a brief, general description of suitable computer hardware
and a suitable computing environment in conjunction with which the
invention may be implemented. Although not required, the invention
is described in the general context of computer-executable
instructions, such as program modules, being executed by a
computer, such as a personal computer. Generally, program modules
include routines, programs, objects, components, data structures,
etc., that perform particular tasks or implement particular
abstract data types.
[0028] Moreover, those skilled in the art will appreciate that the
invention may be practiced with other computer system
configurations, including hand-held devices, multiprocessor
systems, microprocessor-based or programmable consumer electronics,
network PC's, minicomputers, mainframe computers, and the like. The
invention may also be practiced in distributed computing
environments where tasks are performed by remote processing devices
that are linked through a communications network. In a distributed
computing environment, program modules may be located in both local
and remote memory storage devices.
[0029] The exemplary hardware and operating environment of FIG. 1
for implementing the invention includes a general purpose computing
device in the form of a computer 20, including a processing unit
21, a system memory 22, and a system bus 23 that operatively
couples various system components include the system memory to the
processing unit 21. There may be only one or there may be more than
one processing unit 21, such that the processor of computer 20
comprises a single central-processing unit (CPU), or a plurality of
processing units, commonly referred to as a parallel processing
environment. The computer 20 may be a conventional computer, a
distributed computer, or any other type of computer; the invention
is not so limited.
[0030] The system bus 23 may be any of several types of bus
structures including a memory bus or memory controller, a
peripheral bus, and a local bus using any of a variety of bus
architectures. The system memory may also be referred to as simply
the memory, and includes read only memory (ROM) 24 and random
access memory (RAM) 25. A basic input/output system (BIOS) 26,
containing the basic routines that help to transfer information
between elements within the computer 20, such as during start-up,
is stored in ROM 24. The computer 20 further includes a hard disk
drive 27 for reading from and writing to a hard disk, not shown, a
magnetic disk drive 28 for reading from or writing to a removable
magnetic disk 29, and an optical disk drive 30 for reading from or
writing to a removable optical disk 31 such as a CD ROM or other
optical media.
[0031] The hard disk drive 27, magnetic disk drive 28, and optical
disk drive 30 are connected to the system bus 23 by a hard disk
drive interface 32, a magnetic disk drive interface 33, and an
optical disk drive interface 34, respectively. The drives and their
associated computer-readable media provide nonvolatile storage of
computer-readable instructions, data structures, program modules
and other data for the computer 20. It should be appreciated by
those skilled in the art that any type of computer-readable media
which can store data that is accessible by a computer, such as
magnetic cassettes, flash memory cards, digital video disks,
Bernoulli cartridges, random access memories (RAMs), read only
memories (ROMs), and the like, may be used in the exemplary
operating environment.
[0032] A number of program modules may be stored on the hard disk,
magnetic disk 29, optical disk 31, ROM 24, or RAM 25, including an
operating system 35, one or more application programs 36, other
program modules 37, and program data 38. A user may enter commands
and information into the personal computer 20 through input devices
such as a keyboard 40 and pointing device 42. Other input devices
(not shown) may include a microphone, joystick, game pad, satellite
dish, scanner, or the like. These and other input devices are often
connected to the processing unit 21 through a serial port interface
46 that is coupled to the system bus, but may be connected by other
interfaces, such as a parallel port, game port, or a universal
serial bus (USB). A monitor 47 or other type of display device is
also connected to the system bus 23 via an interface, such as a
video adapter 48. In addition to the monitor, computers typically
include other peripheral output devices (not shown), such as
speakers and printers.
[0033] The computer 20 may operate in a networked environment using
logical connections to one or more remote computers, such as remote
computer 49. These logical connections are achieved by a
communication device coupled to or a part of the computer 20; the
invention is not limited to a particular type of communications
device. The remote computer 49 may be another computer, a server, a
router, a network PC, a client, a peer device or other common
network node, and typically includes many or all of the elements
described above relative to the computer 20, although only a memory
storage device 50 has been illustrated in FIG. 1. The logical
connections depicted in FIG. 1 include a local-area network (LAN)
51 and a wide-area network (WAN) 52. Such networking environments
are commonplace in office networks, enterprise-wide computer
networks, intranets and the Internal, which are all types of
networks.
[0034] When used in a LAN-networking environment, the computer 20
is connected to the local network 51 through a network interface or
adapter 53, which is one type of communications device. When used
in a WAN-networking environment, the computer 20 typically includes
a modem 54, a type of communications device, or any other type of
communications device for establishing communications over the wide
area network 52, such as the Internal. The modem 54, which may be
internal or external, is connected to the system bus 23 via the
serial port interface 46. In a networked environment, program
modules depicted relative to the personal computer 20, or portions
thereof, may be stored in the remote memory storage device. It is
appreciated that the network connections shown are exemplary and
other means of and communications devices for establishing a
communications link between the computers may be used.
Generating a Priority for a Text
[0035] In this section of the detailed description, the generation
of a priority for a text such as an email, according to one
embodiment of the invention, is described. The generation of
priorities for texts as described can then be used in methods,
systems, and computer-readable media (as well as other embodiments)
of the invention as are presented in other sections of the detailed
description. The description in this section is provided in
conjunction with FIG. 2 and FIG. 3, the former which is a diagram
showing explicit and implicit training of a text classifier,
according to an embodiment of the invention, and the latter which
is a diagram showing how a priority for a text is generated by
input to a text classifier, according to an embodiment of the
invention. The description is also provided in conjunction with
FIGS. 4(a) and 4(b), which are diagrams of different schema
according to which the priority of a text can be classified, and in
conjunction with FIGS. 5(a) and 5(b), which are graphs showing
different cost functions that may be applicable depending on text
type.
[0036] Referring first to FIG. 2, the text classifier 200 is able
to be trained both explicitly, as represented by the arrow 202, and
implicitly, as represent by the arrow 204. The explicit training
represented by the arrow 202 is usually conducted at the initial
phases of constructing the text classifier 200, while the implicit
training represented by the arrow 204 is usually conducted after
the text classifier 200 has been constructed, to fine tune the
classifier 200. However, the invention is not so limited.
[0037] The text classifier 200 in one embodiment is a Bayesian
classifier, as known within the art, while in another embodiment it
is a support vector machine (SVM) classifier, as also known within
the art. Text classification methodology based on a Bayesian
learning approach is specifically described in the reference M.
Sahami, S. Dumais, D. Heckerman, E. Horvitz, A Bayesian Approach to
Junk E-Mail Filtering, AAAI Workshop on Text Classification, July
1998, Madison, Wis., AAAI Technical Report WS-98-05, which is
hereby incorporated by reference. Text classification methodology
based on an SVM approach is specifically described in the following
references: the coassigned patent, U.S. Pat. No. 5,864,848, issued
Jan. 26, 1999, which is hereby incorporated by reference; the
previously filed and coassigned case entitled "Methods and
Apparatus for Building a Support Vector Machine Classifier," Ser.
No. 09/055,477, filed on Apr. 6, 1998, which is also hereby
incorporated by reference; and, the reference J. Platt, Fast
Training of Support Vector Machines using Sequential Minimal
Optimization, MIT Press, Baltimore, Md., 1998, which is also hereby
incorporated by reference. For purposes of this application,
specific description is made with reference to an SVM classifier,
although those of ordinary skill within the art can appreciate that
the invention is not so limited.
[0038] As shown in FIG. 2, the explicit training of the text
classifier 200 as represented by the arrow 202 includes
constructing the classifier in 206, including utilizing feature
selection. In general, Support Vector Machines build classifiers by
identifying a hyperplane that separates a set of positive and
negative examples with a maximum margin. In the linear form of SVM
that is employed in one embodiment, the margin is defined by the
distance of the hyperplane to the nearest positive and negative
cases for each class. Maximizing the margin can be expressed as an
optimization problem. A post-processing procedure described in the
Platt reference is used that employs regularized maximum likelihood
fitting to produce estimations of posterior probabilities. The
method fits a sigmoid to the score that is output by the SVM
classifier.
[0039] In the explicit training, the text classifier is presented
with both time-critical and non-time-critical texts (e.g., email
messages), so that it may be able to discriminate between the two.
This training set may be provided by the user, or a standard
training set may be used. Given a training corpus, the text
classifier first applies feature-selection procedures that attempt
to find the most discriminatory features. This process employs a
mutual-information analysis. Feature selection can operate on
single words or higher-level distinctions made available, such as
phrases and parts of speech tagged with natural language
processing--that is, the text classifier 200 is able to be seeded
with specially tagged text to discriminate features of a text that
are considered important.
[0040] Feature selection for text classification typically performs
a search over single words. Beyond the reliance on single words,
domain-specific phrases and high-level patterns of features are
also made available. Special tokens can also enhance
classification. The quality of the learned classifiers for email
criticality can be enhanced by inputting to the feature selection
procedures handcrafted features that are identified as being useful
for distinguishing among email of different time criticality. Thus,
during feature selection, single words as well as special phrases
and symbols that are useful for discriminating among messages of
different levels of time criticality are considered.
[0041] Tokens and patterns of value in identifying the criticality
of messages include such distinctions as (including Boolean
combinations thereof):
To: field Addressed just to user Addressed to only a few people
including user Addressed to an alias with a small number of people
Addressed to several aliases with a small number of people Cc:'d to
user Bcc:'d to user
People
[0042] Names on pre-determined list of important people Family
members People at company Organization chart structure [0043]
Managers I report to [0044] Managers of managers of people I report
to [0045] People who report to me External business people Past
tense These include descriptions about events that have already
occurred such as:
We met
[0046] meeting went happened got together took care of meeting
yesterday Future tense
Tomorrow
[0047] This week Are you going to
When can we
[0048] Meeting and coordination Get together Can you meet Will get
together Coordinate with Need to get together Resolved dates Dates
indicated from text and msg. time (e.g., tomorrow, send
yesterday)
Questions
Word+?
[0049] Indications of personal requests:
Can you
Are you
Will you
[0050] you please
Can you do
[0051] Indications of need: I need He needs She needs I'd like It
would be great I want He wants She wants Take care of Time
criticality happening soon right away deadline will be deadline is
as soon as possible needs this soon to be done soon done right
away
Importance
[0052] is important is critical
Word+!
[0053] Explicit priority flag status (low, none, high) Length of
message Number of bytes in component of new message Signs of
Commercial and Adult-Content Junk email
Free!!
[0054] !!!
Under 18
Adult
[0055] Percent caps Percent nonalphanumeric characters etc.
[0056] Other features that may be used for feature selection are
described in the cofiled, copending and coassigned application
entitled "A Computational Architecture for Managing the Transmittal
and Rendering of Information, Alerts, and Notifications," U.S. Ser.
No. 09/365,287, which is hereby incorporated by reference, and in
the copending and coassigned application entitled "Methods and
Apparatus for Building a Support Vector Machine Classifier," U.S.
Ser. No. 09/055,477, filed on Apr. 6, 1998, which has already been
incorporated by reference.
[0057] Furthermore, still referring to FIG. 2, implicit training of
the text classifier 200, as represented by the arrow 204, can be
conducted by continually watching the user work in 210. The
assumption is that as users work, and lists of mail are reviewed,
time-critical messages are read first, and low-priority messages
are reviewed later, or just deleted. That is, when presented with a
new email, the user is watched to determine whether or she
immediately opens the email, and in what order (if more than one
new email are present), deletes the email without opening, and/or
replies to the email right away. Thus, the text classifier is such
that a user is continually watched while working, and the
classifier is continually refined by training in the background and
being updated in real time for decision making. For each message
inputted into the classifier, a new case for the classifier is
created. The cases are stored as negative and positive examples of
texts that are either high or low priority.
[0058] Referring next to FIG. 3, a text, such as an email message,
300 is input into the text classifier 200, which based thereon
generates a priority 302 for the text 300. That is, in one
embodiment, the text classifier 200 generates a priority 302,
measured as a percentage from 0 to 1 (i.e., 0% to 100%). This
percentage is a measure of the likelihood that the text 300 is of
high priority, based on the previous training of the classifier
200.
[0059] It is noted that as has been described, the text classifier
and the priority generated thereby is based on a scheme where each
email in the training phase is construed as either high priority or
low priority, such that the priority generated by the text
classifier is a measure of the likelihood of the text being
analyzed is of high priority. This scheme is specifically shown by
reference to FIG. 4(a), where the text classifier 200 is trained by
a group of texts 400 that are high priority and a group of texts
402 that are low priority, such that a text to be analyzed 400 is
input into the classifier 200, which outputs a scalar number 406
measuring the likelihood that the text being analyzed is of high
priority. However, those of ordinary skill within the art can
appreciate that the invention is not so limited.
[0060] For example, referring to FIG. 4(b), a diagram showing a
scheme where texts are divided into low, medium and high priority,
according to an embodiment of the invention, is shown. The text
classifier 200 in the embodiment of FIG. 4(b) is trained by a group
of texts 400 that are high priority and a group of texts 402 that
are low priority, as in the previous embodiment, but also by a
group of texts 450 that are medium priority. Thus, a text to be
analyzed 400 is input into the classifier 200, which outputs a
scalar number 406, that can measure the likelihood that the text
being analyzed is of high priority, if so desired, or medium
priority or low priority. The classifier 200 is also able to output
a class 452, which indicates the class of low, medium or high
priority that the text 404 most likely falls into. Those of
ordinary skill within the art can appreciate that further classes
can also be added if desired.
[0061] The invention is not limited to the definition of priority
as this term is used by the text classifier to assign such priority
to a text such as an email message. In one embodiment, however,
priority is defined in terms of a loss function. More specifically,
priority is defined in terms of the expected cost in lost
opportunities per time delayed in reviewing the text after it has
be received--that is, the expected lost or cost that will result
for delayed processing of the text. This loss function can further
vary according to the type of text received.
[0062] For example, the general case is shown in FIG. 5(a), which
is a graph of linear cost functions dependent on the priority of a
text. In the graph 500, as time increases, the cost of not having
reviewed a text also increases. However, the cost increases more
for a high priority message, as indicated by the line 502, as
compared to a medium priority message, as indicated by the line
504, or a low priority message, as indicated by the line 506. That
is, the high priority line 502 may have a slope of 100, the medium
priority line 504 may have a slope of 10, and the low priority line
502 may have a slope of 1. These slope values can then be used by
the text classifier to assist in assigning a priority to a given
text, for example, by regression analysis.
[0063] Some messages, however, do not have their priorities well
approximated by the use of a linear cost function. For example, a
message relating to a meeting will have its cost function increase
as the time of the meeting nears, and thereafter, the cost function
rapidly decreases--since after the meeting is missed, there is not
much generally a user can do about it. This situation is better
approximated by a non-linear cost function, as shown in FIG. 5(b).
In the graph 550, the cost function 554 rapidly increases until it
reaches the time of the meeting demarcated by the line 552, after
which it rapidly decreases. Thus, those of ordinary skill within
the art can appreciate that depending on a message's type, the cost
function can be approximated by one of many different
representative cost functions, both linear and non-linear.
[0064] Thus, as has been described, the priority of a text can be
just the likelihood that it is of high priority based on output of
a text classifier, or the most likely priority class (i.e., medium,
low or high priority) it falls into, also based on the output of
the text classifier. However, in another embodiment of the
invention, an expected time criticality of each text, such as an
email message, is determined. This can be written as
EL = i n p ( critical i ) C ( critical i ) ##EQU00001##
where EL is the expected loss, p(critical.sub.i) is the probability
that a text has the criticality i (e.g., where i=0 may be low
priority and i=1 may be high priority, or where i=0 may be low
priority, i=1 medium priority and i=2 high priority, etc.),
C(critical.sub.i) is the cost function for text having the
criticality i, and n is the total number of criticality classes
minus one. The cost functions may be linear or non-linear, as has
been described--in the case where the function are linear, the cost
function is thus the rate of loss.
[0065] In the case where n=1, specifying that there are only two
priority classes low and high, the expected loss can be
reformulated as
EC=p(critical.sub.high)C(critical.sub.high)+[1-p(critical.sub.low)]C(cri-
tical.sub.low)
where EC is the expected criticality of a text. Furthermore, if the
cost function of low criticality messages is set to zero, this
becomes
EC=p(critical.sub.high)C(critical.sub.high)
The total loss until the time of review of a text can be expressed
as the integration of the expressed criticality, or,
EL=.intg..sub.0.sup.tp(critical.sub.high)C(critical.sub.high)
where t is the time of review. Determining when to Alert the
User
[0066] In this section of the detailed description, described is
provided as to determining when to alert the user of a
high-priority text, for example, a text that has a likelihood of
being high priority greater than a user-set threshold, or greater
than a threshold determined by decision theoretic reasoning. That
is, beyond knowing about time critical messages, it is also
important in one embodiment to decide when to alert a user to
time-critical messages if the user is not directly viewing incoming
email (in one embodiment). In the general case, a cost of
distracting the user from the current task being addressed to learn
about the time-critical message is determined
[0067] In general, a user should be alerted when a cost-benefit
analysis suggests that the expected loss the user would incur in
not reviewing the message at time t is greater than the expected
cost of alerting the user. That is, alerting should be conducted
if
EL-EC>0
where EL is the expected loss of non-review of the text at a
current time t, and EC is the expected cost of alerting the user of
the text at the current time t. The expected loss is as described
in the previous section of the detailed description.
[0068] However, this formulation is not entirely accurate, because
the user is assumed to review the message on his or her own at some
point in the future anyway. Therefore, in actuality, the user
should be alerted when the expected value of alerting, referred to
as ECA, is positive. The expected value of alerting should thus
consider the value of alerting the user of the text now, as opposed
to the value of the user reviewing the message later on his or her
own, without alert, minus the cost of alerting. This can be stated
as
EVA=EL.sub.alert-EL.sub.no-alert-EC
where EL.sub.alert is the expected loss of the user reviewing the
message if he or she were to review the message now, upon being
alerted, as opposed to EL.sub.no-alert, which is the expected loss
of the user reviewing the message on his or her own at some point,
without being alerted, minus EC, the expected cost of alerting
(now).
[0069] Furthermore, in one specific embodiment of the invention,
information from several messages are grouped together into a
single compound alert. Reviewing information about multiple
messages in an alert can be more costly than an alert relaying
information about a single messages. Such increases in distraction
can be represented by making the cost of an alert a function of its
informational complexity. It is assumed that the EVA of an email
message is independent of the EVA of the other email messages.
EVA(M.sub.i,t) is used to refer to the value of alerting a user
about a single message M.sub.i at time t and ECA(n) is used to
refer to the expected cost of relaying the content of n messages.
Thus, multiple messages can be considered by summing together the
expected value of relaying information about a set of n
messages,
NEVA = i = 1 EVA ( M i , t ) - ECA ( n ) . ##EQU00002##
[0070] In one embodiment of the invention, it is noted that
determining when to alert the user is conducted in accordance with
the more rigorous treatment of EVA described in the copending,
cofiled and coassigned application entitled "A Computational
Architecture for Managing the Transmittal and Rendering of
Information, Alerts, and Notifications," U.S. Ser. No. 09/365,287,
which is hereby incorporated by reference. However, the invention
is not so limited.
[0071] It is also noted that in order to determine the expect cost
of alerting, it is useful to infer or directly access information
about whether the user is present--and therefore can see or hear
alerts from the computer--or is not present. Sensors can be used in
one embodiment that indicate when a user is in the office, such as
infrared sensors, pressure sensors (on the chair), etc. However, if
such devices are not available, a probability that a user is in the
office can be assigned as a function of user activity on the
computer, such as the time since last observed mouse or keyboard
activity. Furthermore, scheduling information available in a
calendar can also be made use of to make inferences about the
distance and disposition of a user, to consider the costs of
forwarding messages to the user by different means (e.g., cell
phone, pager, etc.).
[0072] It is also important to know how busy the user is in making
decisions about interrupting the user with information about
messages with high time criticality. In one embodiment, it is
reasoned about whether and the rate at which a user is working on a
computer, or whether the user is on the telephone, speaking with
someone, or at a meeting at another location. In one embodiment,
several classes of evidence can be used to assess a user's activity
or his or her focus of attention, as shown in FIG. 6. A Bayesian
network, as known in the art, can then be used for performing an
inference about a user's activity; an example of such a network is
shown in FIG. 7. Utilizing evidence to infer whether the user is
present is described more rigorously in the cofiled, copending and
coassigned application entitled "A Computational Architecture for
Managing the Transmittal and Rendering of Information, Alerts, and
Notifications," U.S. Ser. No. 09/365,287, which has already been
incorporated by reference (specifically, with respect to
determining an alert-reception probability). Thus, in one
embodiment, a probability inference as to whether a user is present
is determined in accordance with the description provided in this
application.
[0073] In general, a decision should be made as to when and how to
alert users to messages and to provide services (for example) based
on the inference of expected criticality and user activity. In one
embodiment, this decision is made as described in the cofiled,
copending and coassigned application entitled "A Computational
Architecture for Managing the Transmittal and Rendering of
Information, Alerts, and Notifications," U.S. Ser. No. 09/365,287,
which has already been incorporated by reference (specifically,
with respect to the attention management module).
[0074] In another embodiment, this decision is made by utilizing
decision models, as known within the art. FIGS. 8-10 are influence
diagrams, as known within the art, showing how in one specific
embodiment such decision models can be utilized to make this
decision. Specifically, FIG. 8 displays a decision model for
decisions about interrupting a user, considering current activity,
expected time criticality of messages, and cost of alerting
depending on the modality. FIG. 9 also includes variables
representing the current location and the influence of that
variable on activity and cost of the alternate messaging
techniques. Finally, FIG. 10 is further expanded to consider the
costs associated with losses in fidelity when a message with
significant graphics content is forwarded to a user without the
graphical content being present.
[0075] In still another embodiment, the decision as to when and how
to alerts users is made by employment of a set of user-specified
thresholds and parameters defining policies on alerting. In this
embodiment, user presence can be inferred based on mouse or
keyboard activity. Thus, a user can be allowed to input distinct
thresholds on alerting for inferred states of activity and
nonactivity. Users can input an amount of idle activity following
activity where alerting will occur at lower criticalities. In this
embodiment, if it is determined that the user is not available
based on the time that no computer activity is seen--or on the
user's inactivity when an attempt to alert is made--then messages
and stored, and are reported to the user in order of criticality
when the user returns to interact with the computer (or, returns to
the room, given the availability of inputs from infrared or other
presence detection).
[0076] Furthermore, in this embodiment, users can specify routing
and paging options (as well as other output options) as a function
of quantities including expected criticality, maximum expected
loss, and value of alerting the user. Such routing, paging and
other output options are more specifically described in the
copending, cofiled, and coassigned applications entitled "Methods
for Routing Documents based on a Measure of Criticality," U.S. Ser.
No. 09/364,528, "Methods for Display, Notification, and Interaction
with Prioritized Messages," U.S. Ser. No. 09/364,522, which are all
hereby incorporated by reference. The invention is not so limited,
however.
Method and System
[0077] In this section of the detailed description, a
computer-implemented method according to an embodiment of the
invention is described, and a computerized system according to an
embodiment of the invention is described. With respect to the
method, the method is desirably realized at least in part as one or
more programs running on a computer--that is, as a program executed
from a computer-readable medium such as a memory by a processor of
a computer. The program is desirably storable on a machine-readable
medium such as a floppy disk or a CD-ROM, for distribution and
installation and execution on another computer.
[0078] Referring to FIG. 11, a flowchart of a method according to
an embodiment of the invention is shown. In 900, a text to have a
priority thereof assigned is received. The text can be an email
message, or any other type of text; the invention is not so
limited. In 902, the priority of the text is generated, based on a
text classifier, as has been described. Thus, in one embodiment,
902 includes initially training and continually training the text
classifier, as has been described.
[0079] The priority of the text is then output in 904. In one
embodiment, as indicated in FIG. 11, this can include 906, 908,
910, 912 and 914; however, the invention is not so limited. In 906,
an expected loss of non-review of the text at a current time t is
determined--in one embodiment, by also considering the expected
loss of now-review of the text at a future time, based on the
assumption that ultimately the user will review the text him or
herself, without being alerted, as has been described. In 908, an
expected cost of alerting is determined, as has also been
described. If the loss is greater than the cost in 910, then no
alert is made at the time t, and the method proceeds back to 906,
to redetermine the cost-benefit analysis, at a new current time t.
This is done because as time progresses, the expected loss may at
some point outweigh the alert cost, such that the calculus in 910
changes. Upon the expected loss outweighing the alert cost, then an
alert to the user is performed in 914, as has been described.
[0080] In one embodiment, the output of the alert is performed as
is now described. A user is alerted on an electronic device based
on an alert criteria, which indicates when the user should be
alerted of a prioritized text. Alert criteria that can be used in
conjunction with embodiments of the invention is not limited by the
invention; however, in one embodiment, the alert criteria is as
described in a further section of the detailed description. The
electronic device on which the user is alerted can in one
embodiment be a pager or a cellular telephone; however, the
invention is not so limited.
[0081] In one embodiment, the method alerts a user on an electronic
device, such as a pager or a cellular phone, based on an alert
criteria that can be made sensitive to information about the
location, inferred task, and focus of attention of the user. Such
information can be inferred under uncertainty or can be accessed
directly from online information sources. One embodiment makes use
of information from an online calendar to control the criteria used
to make decisions about relaying information to a mobile
device.
[0082] Referring next to FIG. 12, a diagram of a system according
to an embodiment of the invention is shown. The system includes a
program 950 and a text classifier 952. Each of the program 950 and
the classifier 952 include a computer program executed by a
processor of a computer from a computer-readable medium thereof, in
one embodiment. However, the invention is not so limited.
[0083] The program 950 generates a text for input into the text
classifier 952. In one embodiment, the program includes an
electronic mail program that receives email, which then serve as
the text. The text classifier 952, based on the text, generates a
priority thereof, as has been described. In one embodiment, the
text classifier 952 is a Bayesian text classifier, while in another
embodiment, it is a Support Vector Machine classifier. The priority
of the text output by the text classifier 952 can then be used in
further conjunction with a cost-benefit analysis, as has been
described, to effectuate further output and/or alerting based
thereon, as has been described. The invention is not so limited,
however.
[0084] Referring next to FIG. 13, a diagram of a system according
to another embodiment of the invention is shown. The system of FIG.
13 includes an additional component, an alert mechanism 970. Not
shown in FIG. 13 are the program 950 and the text classifier 952;
however, the alert mechanism 970 is operatively and/or
communicatively coupled to the latter. In one embodiment, the
mechanism 970 includes a computer program executed by a processor
of a computer from a computer-readable medium thereof, but the
invention is not so limited.
[0085] As shown in FIG. 13, the alert mechanism 970 is
communicatively coupled to the Internet 972, which is the network
by which the alert mechanism 970 contacts an electronic device to
alert the user to a prioritized text, based on an alert criteria,
in one embodiment. The network is not limited to the Internet 972,
however. Thus, the alert mechanism 970 is able to alert the user of
a prioritized text via contacting a pager 974, or a cellular phone
976, or other electronic devices capable of receiving information
from over a network such as the Internet 972, and which are not
shown in FIG. 13. The invention is not limited as to a particular
alert criteria, although in one embodiment, the alert criteria is
as described in the next section of the detailed description.
Alert Criteria
[0086] In this section of the detailed description, an alert
criteria according to one embodiment of the invention is described.
The alert criteria is the criteria that governs when and how a user
is alerted to a prioritized text. The alert criteria is described
with reference to FIG. 14, which is a diagram of a user interface
via which alert criteria options can be modified, according to one
embodiment of the invention.
[0087] Referring now to FIG. 14, in text entry box 980, the user is
able to enter the email address of a pager or a cellular phone on
which the user would like to be notified of prioritized text. As
known within the art, pagers and cellular phones are available that
allow for paging by emailing text to an email address assigned to
the pager or cellular phone. For example, as shown in FIG. 14, the
device has an email address 4255555555@mobile.phoneco.net, where
4255555555 corresponds to the phone number of the cellular phone or
the pager number of the pager, as provided by the phone company
"phoneco."
[0088] It is noted that the alert criteria of FIG. 14 specifically
relates to new email messages, but that the invention is not so
limited. Three alert criteria are specifically shown in FIG. 14,
and are referred to as options 982, 984 and 986. The options are
not mutually exclusive, however. That is, the user can select one,
two, or all three of the options 982, 984 and 986.
[0089] In the option 982, the user is able to specify that the
electronic device should be contacted if a new email is received
that has a priority greater than a predetermined threshold, and the
user has been away from the computer for more than a predetermined
amount of time. As shown in FIG. 14, the predetermined threshold is
a priority of 85, while the predetermined amount of time is 75
minutes. Thus, if it is determined that the priority of an email
message is greater than 85, and that the user has been away from
the computer for more than 75 minutes, then the user's electronic
device will be alerted, consistent with the other options 984
and/or 986 if selected.
[0090] In the option 984, the user is able to specify that the
electronic device should be contacted only when the current time is
within a predetermined range of times. As shown in FIG. 14, the
predetermined range of times is between 8:15 a.m. and 7:30 p.m.
Thus, if it is determined that the current time is between 8:15
a.m. and 7:30 p.m., then the user's electronic device will be
alerted, consistent with the other options 982 and/or 986 if
selected.
[0091] In the option 986, the user is able to specific that if the
user is in a meeting--for example, as determined by examining a
schedule of the user--then the user should only be notified if the
priority is greater than a predetermined meeting threshold. In
general, this meeting threshold is desirably greater than the
threshold specified in the option 982--the purpose of this greater
threshold is to indicate that the user is receptive to notification
of email messages greater than a particular priority in usual
circumstances, but that the user is receptive to notification of
email messages during meetings only if they have a priority that is
unusually great. As shown in FIG. 14, then, the predetermined
meeting threshold is a priority of 95, which is higher than the
predetermined threshold of 85 in the option 982. Thus, if it is
determined that the user is in a meeting, and a message is received
having a threshold greater than 95, then the user is alerted via
his or her electronic device.
EXAMPLE EMBODIMENTS
[0092] In one embodiment, a computer-implemented method comprises:
receiving a text;
generating a priority of the text based on a text classifier; and,
alerting a user on an electronic device based on an alert
criteria.
[0093] In an embodiment, the alert criteria is sensitive to
information about location, inferred task, and focus of attention
of the user.
[0094] In an embodiment, the information is inferred under
uncertainty.
[0095] In an embodiment, the information is accessed directly from
online information sources.
[0096] In an embodiment, the online information sources comprises
an online calendar.
[0097] In an embodiment, the receiving a text comprises receiving
an email.
[0098] In an embodiment, the alerting a user on an electronic
device comprises alerting the user on the electronic device
comprising a pager.
[0099] In an embodiment, the alerting a user on an electronic
device comprises alerting the user on the electronic device
comprising a cellular phone.
[0100] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether
the priority of the text is greater than a predetermined threshold;
and, alerting the user upon determining that the priority of the
text is greater than the predetermined threshold.
[0101] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether
the priority of the text is greater than a predetermined threshold;
determining whether the user has been away for more than a
predetermined amount of time; and, upon determining that the
priority of the text is greater than the predetermined threshold
and that the user has been away for more than the predetermined
amount of time, alerting the user.
[0102] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether a
current time is within a predetermined range of times; and, upon
determining that the current time is within the predetermined range
of times, alerting the user.
[0103] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether
the user is in a meeting; upon determining that the user is in a
meeting, determining whether the priority is greater than a
predetermined meeting threshold; and, upon determining that the
priority is greater than the predetermined meeting threshold,
alerting the user.
[0104] In another embodiment, a computer-implemented method
comprises: training a text classifier comprising one of a Bayesian
classifier and a support-vector machine classifier; receiving a
text comprising an email; generating a priority of the text based
on the text classifier; and, alerting a user on an electronic
device based on an alert criteria.
[0105] In an embodiment, the alerting a user on an electronic
device comprises alerting the user on the electronic device
comprising one of a pager and a cellular phone.
[0106] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether
the priority of the text is greater than a predetermined threshold;
and, alerting the user upon determining that the priority of the
text is greater than the predetermined threshold.
[0107] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether
the priority of the text is greater than a predetermined threshold;
determining whether the user has been away for more than a
predetermined amount of time; and, upon determining that the
priority of the text is greater than the predetermined threshold
and that the user has been away for more than the predetermined
amount of time, alerting the user.
[0108] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether
the priority of the text is greater than a predetermined threshold;
determining whether the user has been away for more than a
predetermined amount of time; determining whether a current time is
within a predetermined range of times; and, upon determining that
the priority of the text is greater than the predetermined
threshold, that the user has been away for more than the
predetermined amount of time, and that the current time is within
the predetermined range of times, alerting the user.
[0109] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether
the user is in a meeting; upon determining that the user is in a
meeting, determining whether the priority is greater than a
predetermined meeting threshold; and, upon determining that the
priority is greater than the predetermined meeting threshold,
alerting the user.
[0110] In another embodiment, a machine-readable medium has
instructions stored thereon for execution by a processor to perform
a method comprising: receiving a text; generating a priority of the
text based on a text classifier; and, alerting a user on an
electronic device based on an alert criteria.
[0111] In an embodiment, the receiving a text comprises receiving
an email.
[0112] In an embodiment, the alerting a user on an electronic
device comprises alerting the user on the electronic device
comprising a pager.
[0113] In an embodiment, the alerting a user on an electronic
device comprises alerting the user on the electronic device
comprising a cellular phone.
[0114] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether
the priority of the text is greater than a predetermined threshold;
and, alerting the user upon determining that the priority of the
text is greater than the predetermined threshold.
[0115] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether
the priority of the text is greater than a predetermined threshold;
determining whether the user has been away for more than a
predetermined amount of time; and, upon determining that the
priority of the text is greater than the predetermined threshold
and that the user has been away for more than the predetermined
amount of time, alerting the user.
[0116] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether a
current time is within a predetermined range of times; and, upon
determining that the current time is within the predetermined range
of times, alerting the user.
[0117] In an embodiment, the alerting a user on an electronic
device based on an alert criteria comprises: determining whether
the user is in a meeting; upon determining that the user is in a
meeting, determining whether the priority is greater than a
predetermined meeting threshold; and, upon determining that the
priority is greater than the predetermined meeting threshold,
alerting the user.
[0118] In another embodiment, a computerized system comprises: a
program to generate a text; a text classifier to generate a
priority of the text; and, an alert mechanism to alert a user on an
electronic device based on an alert criteria.
[0119] In an embodiment, the program comprises an electronic mail
program to receive an electronic mail as the text.
[0120] In an embodiment, the text classifier comprises a Bayesian
text classifier.
[0121] In an embodiment, the text classifier comprises a
support-vector-machine classifier.
[0122] In an embodiment, the electronic device comprises one of a
pager and a cellular phone.
[0123] In an embodiment, the alert criteria comprises a
determination of whether the priority of the text is greater than a
predetermined threshold.
[0124] In an embodiment, the alert criteria comprises a
determination of whether the priority of the text is greater than a
predetermined threshold and whether the user has been away for more
than a predetermined amount of time.
[0125] In an embodiment, the alert criteria comprises a
determination of whether a current time is within a predetermined
range of times.
[0126] In an embodiment, the alert criteria comprises a
determination of whether the user is in a meeting and whether the
priority is greater than a predetermined meeting threshold.
[0127] In an embodiment, at least one of the alert mechanism, the
program and the text classifier comprise a computer program
executed by a processor from a computer-readable medium.
CONCLUSION
[0128] Although specific embodiments have been illustrated and
described herein, it will be appreciated by those of ordinary skill
in the art that any arrangement which is calculated to achieve the
same purpose may be substituted for the specific embodiments shown.
This application is intended to cover any adaptations or variations
of the present invention. Therefore, it is manifestly intended that
this invention be limited only by the following claims and
equivalents thereof
* * * * *