Akhilesh Bajaj

A feedback model to understand information system usage

A significant portion of the risk that is assumed by the developer of an information system (IS) is whether end-users will actually use it. Past models in IS research have listed external variables (such as technical features and organizational environment) as well as internal psychological variables (such as past education and attitude to system use) as influencing the continued usage of the IS. In this work, we extend these models and propose and test a new model that posits that attitudes may also be shaped by past behavior (usage of the system). Past usage apparently influences the ease of use of the system and this is a key factor in determining future usage. A longitudinal model was tested using statistical panel data techniques with instrumental constructs. The model has implications for IS theory as well as providing guidelines for industry on the implementation of new ISs.

Managing NPD: Cost and Schedule Performance in Design and Manufacturing

In this field study, conducted at a leading avionics guidance systems manufacturer, we gathered primary data on time and cost performance of both the design and manufacturing phases of new product development (NPD). We modeled the impact of the management levers relating to oversight, the intensity of design specialization, and the level of interaction with the customer. The study highlights the necessity of leveraging the interdependencies between the design and manufacturing phases in NPD.

SEAM: A state-entity-activity-model for a well-defined workflow development methodology

Current conceptual workflow models use either informally defined conceptual models or several formally defined conceptual models that capture different aspects of the workflow, e.g., the data, process, and organizational aspects of the workflow. To the best of our knowledge, there are no algorithms that can amalgamate these models to yield a single view of reality. A fragmented conceptual view is useful for systems analysis and documentation. However, it fails to realize the potential of conceptual models to provide a convenient interface to automate the design and management of workflows. First, as a step toward accomplishing this objective, we propose SEAM (State-Entity-Activity-Model), a conceptual workflow model defined in terms of set theory. Second, no attempt has been made, to the best of our knowledge, to incorporate time into a conceptual workflow model. SEAM incorporates the temporal aspect of workflows. Third, we apply SEAM to a real-life organizational units workflows. In this work, we show a subset of the workflows modeled for this organization using SEAM. We also demonstrate, via a prototype application, how the SEAM schema can be implemented on a relational database management system. We present the lessons we learned about the advantages obtained for the organization and, for developers who choose to use SEAM, we also present potential pitfalls in using the SEAM methodology to build workflow systems on relational platforms. The information contained in this work is sufficient enough to allow application developers to utilize SEAM as a methodology to analyze, design, and construct workflow applications on current relational database management systems. The definition of SEAM as a context-free grammar, definition of its semantics, and its mapping to relational platforms should be sufficient also, to allow the construction of an automated workflow design and construction tool with SEAM as the user interface.

Multiclass transaction scheduling and overload management in firm real-time database systems

Real-Time Database Systems (RTDBSs), have attracted considerable amount of research attention in the recent past and a number of important applications have been identified for such systems, such as telecommunications network management, automated air traffic control, automated financial trading, process control and military command and control systems. Due to the rapidity of change of the system state in such applications, as well as the inherent complexities in controlling such systems (which result in frequent violation of consistency requirements and consequent repeated firings of control actions), it is likely that the transaction load in these systems would be fairly high. Thus RTDBSs need to be equipped with overload management mechanisms. Unfortunately overload management has been a fairly neglected area in real-time systems research in general and real-time database research in particular. In this paper we introduce Adaptive Access Parameter (AAP), a scheduling mechanism for multiclass transactions in real-time database systems that employs an explicit admission control policy to manage overload as well as system bias towards particular transaction classes. We show the theoretical underpinnings behind AAP and then report a thorough performance study that demonstrates AAPs substantial superiority over current algorithms with regard to performance metrics as well as computational overhead.

The effect of the number of concepts on the readability of schemas: an empirical study with data models

The number of concepts in a model has been frequently used in the literature to measure the ease of use in creating model schemas. However, to the best of our knowledge, nobody has looked at its effect on the readability of the model schemas after they have been created. The readability of a model schema is important in situations where the schemas are created by one team of analysts and read by other analysts, system developers, or maintenance administrators. Given the recent trend of models with increasing numbers of concepts such as the unified modeling language (UML), the effect of the number of concepts (NOC) on the readability of schemas has become increasingly important. In this work, we operationalize readability along three dimensions: effectiveness, efficiency, and learnability. We draw on the Bunge Wand Weber (BWW) framework, as well as the signal detection recognition theory and the ACT theory from cognitive psychology to formulate hypotheses and conduct an experiment to study the effects of the NOC in a data model on these readability dimensions. Our work makes the following contributions: (a) it extends the operationalization of the readability construct, and (b) unlike earlier empirical work that has focused exclusively on comparing models that differ along several dimensions, this work proposes an empirical methodology that isolates the effect of a model-independent variable (the NOC) on readability. From a practical perspective, our findings have implications both for creators of new models, as well as for practitioners who use currently available models for creating schemas to communicate requirements during the entire lifecycle of a system.

IAIS: A methodology to enable inter-agency information sharing in eGovernment

Recently, there has been increased interest in information sharing among government agencies, with a view toward improving security, reducing costs and offering better quality service to users of government services. In this work, the authors complement earlier work by proposing a comprehensive methodology called IAIS (Inter Agency Information Sharing) that uses XML to facilitate the definition of information that needs to be shared, the storage of such information, the access to this information and finally the maintenance of shared information. The authors compare IAIS with two alternate methodologies to share information among agencies, and analyze the pros and cons of each. They also show how IAIS leverages the recently proposed XML (extensible markup language) standard to allow for inclusion of various groups’ viewpoints when determining what information should be shared and how it should be structured.

AWSM: Allocation of workflows utilizing social network metrics

The primary contribution of this work is a methodology that serves as a decision support tool to create teams of human actors within an organization to perform workflows, based on optimizing social network (SN) measures of choice, such as group or team cohesiveness. Past literature shows that the constituent activities of the workflows will be performed with greater efficiency and/or effectiveness if the workgroup of actors is optimized along an SN measure such as group cohesiveness. The major contribution here is the creation and implementation of a formal generalized methodology we call AWSM (Allocation of Workflows with Social Network Metrics) that incorporates ideas from two diverse fields: social network theory and workflow modeling, and allows optimization of work groups along any SN metric. In order to implement this model we present newly created algorithms to structure and represent the problem so that standard integer programming solvers can be utilized to solve it. We also present a performance analysis of the AWSM methodology and empirically test its feasibility for solving real world sized problems.

CMU-WEB: a conceptual model for designing usable web applications

With the ubiquitous availability of browsers and internet access, the last few years have seen a tremendous growth in the number of applications being developed on the world wide web (WWW). Models for analyzing and designing these applications are only just beginning to emerge. In this work, we propose a 3-dimensional classification space for WWW applications, consisting of a degree of structure of pages dimension, a degree of support for interrelated events dimension and a location of processing dimension. Next, we propose usability design metrics for WWW applications along the structure of pages dimension. To measure these ,we propose CMU-WEB: a conceptual model that can be used to design WWW applications, such that its schemas provide values for the design metrics. This work represents the first effort, to the best of our knowledge, to provide a conceptual model that measures quantifiable metrics that can be used for the design of more usable web applications, and that can also be used to compare the usability of existing web applications, without empirical testing.

SAAS: Integrating Systems Analysis with Accounting and Strategy for Ex Ante Evaluation of IS Investments

For many companies, investment in information systems (IS) is one of the largest expenditures in the firms capital budget. An important goal of ex ante investment evaluation of an information system is to reasonably determine the return on investment (ROI) of the proposed information system. However, past research has shown that business managers have significant concerns about the soundness of ex ante ROI evaluations of information systems. This relates to the fact that several benefits of an IS are intangible and nonfinancial. In addition, it has long been recognized that, unlike many other capital projects, IS projects exhibit significant contextual interaction. Further, different professionals such as accountants and Information Technology (IT) personnel often use different approaches to evaluate a potential information system. This study develops a framework and methodology that integrates and accommodates the different perspectives of IT personnel, accountants, and business managers. We propose a f...

A Comprehensive Framework Towards Information Sharing Between Government Agencies

Recently, there has been increased interest in sharing digitized information between government agencies, with the goals of improving security, reducing costs, and offering better quality service to users of government services. The bulk of previous work in interagency information sharing has focused largely on the sharing of structured information among heterogeneous data sources, whereas government agencies need to share data with varying degrees of structure ranging from free text documents to relational data. In this work, we explore the different technologies available to share information. Specifically, our framework discusses the optional data storage mechanisms required to support a Service Oriented Architecture (SOA). We compare XML document, free text search engine, and relational database technologies and analyze the pros and cons of each approach. We explore these options along the dimensions of information definition, information storage, the access to this information, and finally the maintenance of shared information.