March 1995 - Vol. 38 No. 3

March 1995 issue cover image

Features

Opinion

The Internet is not TV: Web publishing

Don't turn the page. This is not yet-another article on how great the World-Wide Web is, and how fast it is growing. By now you must have read many of those, and surfed the Web a bit. But, the Internet is not television—are you ready to become a Web author? This article describes tools and considerations for publishing on them Web, and looks toward the future. Let's start with server platfroms.
Research and Advances

Bayesian networks

This brief tutorial on Bayesian networks serves to introduce readers to some of the concepts, terminology, and notation employed by articles in this special section. In a Bayesian network, a variable takes on values from a collection of mutually exclusive and collective exhaustive states. A variable may be discrete, having a finite or countable number of states, or it may be continuous. Often the choice of states itself presents an interesting modeling question. For example, in a system for troubleshooting a problem with printing, we may choose to model the variable “print output” with two states—“present” and “absent”—or we may want to model the variable with finer distinctions such as “absent,” “blurred ,” “cut off,” and “ok.”
Research and Advances

Structure and chance: melding logic and probability for software debugging

Software errors abound in the world of computing. Sophisticated computer programs rank high on the list of the most complex systems ever created by humankind. The complexity of a program or a set of interacting programs makes it extremely difficult to perform offline verification of run-time behavior. Thus, the creation and maintenance of program code is often linked to a process of incremental refinement and ongoing detection and correction of errors. To be sure, the detection and repair of program errors is an inescapable part of the process of software development. However, run-time software errors may be discovered in fielded applications days, months, or even years after the software was last modified—especially in applications composed of a plethora of separate programs created and updated by different people at different times. In such complex applications, software errors are revealed through the run-time interaction of hundreds of distinct processes competing for limited memory and CPU resources. Software developers and support engineers responsible for correcting software problems face difficult challenges in tracking down the source of run-time errors in complex applications. The information made available to engineers about the nature of a failure often leaves open a wide range of possibilities that must be sifted through carefully in searching for an underlying error.
Research and Advances

Applying Bayesian networks to information retrieval

Information retrieval (IR) is the identification of documents or other units of information in a collection that are relevant to a particular information need. An information need is a set of questions to which someone would like to find an answer. Here are some examples of IR tasks: finding articles in the New York Times that discuss the Iran-Contra affair; searching the recent postings in a Usenet newsgroup for references to a particular model of personal computer; finding the entries referring to butterflies in an online CD-ROM encyclopedia.
Research and Advances

Temporal difference learning and TD-Gammon

Ever since the days of Shannon's proposal for a chess-playing algorithm [12] and Samuel's checkers-learning program [10] the domain of complex board games such as Go, chess, checkers, Othello, and backgammon has been widely regarded as an ideal testing ground for exploring a variety of concepts and approaches in artificial intelligence and machine learning. Such board games offer the challenge of tremendous complexity and sophistication required to play at expert level. At the same time, the problem inputs and performance measures are clear-cut and well defined, and the game environment is readily automated in that it is easy to simulate the board, the rules of legal play, and the rules regarding when the game is over and determining the outcome.
Research and Advances

Coordination in software development

Since its inception, the software industry has been in crisis. As Blazer noted 20 years ago, “[Software] is unreliable, delivered late, unresponsive to change, inefficient, and expensive … and has been for the past 20 years” [4]. In a survey of software contractors and government contract officers, over half of the respondents believed that calendar overruns, cost overruns, code that required in-house modifications before being usable, and code that was difficult to modify were common problems in the software projects they supervised [22]. Even today, problems with software systems are common and highly-publicized occurrences.
Research and Advances

Race differences in job performance and career success

Although blacks have gained entry to the information systems (IS) field and various managerial positions, they continue to experience more restricted career advancement prospects than whites. They have found it difficult to advance professionally and managerially within their organizations. Perhaps, as the management literature suggests, this is because minorities may experience considerable discrimination in their jobs that lowers their performance and ultimately impedes their career advancement [10].
Opinion

To take arms against a sea of email

The rapid growth of the Internet means there is more email traffic now than ever before, and there will be still more in years to come. There was a time when only hard-core hackers had to deal with significant amounts of email. As email becomes a standard medium of communication, and more and more nonprogrammers join mailing lists, an increasing number of people find themselves receiving large amounts of email and must cope with it.

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