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Derivation of Probability Density Functions for the Relative Differences in the Standard and Poor's 100 Stock Index Over Various Intervals of Time

Description: In this study a two-part mixed probability density function was derived which described the relative changes in the Standard and Poor's 100 Stock Index over various intervals of time. The density function is a mixture of two different halves of normal distributions. Optimal values for the standard deviations for the two halves and the mean are given. Also, a general form of the function is given which uses linear regression models to estimate the standard deviations and the means. The density functions allow stock market participants trading index options and futures contracts on the S & P 100 Stock Index to determine probabilities of success or failure of trades involving price movements of certain magnitudes in given lengths of time.
Date: August 1988
Creator: Bunger, R. C. (Robert Charles)

Empirical Research of Decision-making Effectiveness When Using Differing Presentation Formats Under Varying Decision Tasks

Description: The purpose of this research was to determine if presentation format, given a particular task to be performed, would affect the decision-making process of financial decision makers. The problem motivating this study is the potential for managers to make inefficient decisions when they use reports which are presented inappropriately for a given task.
Date: December 1988
Creator: Hard, Nancy J. (Nancy Jean)

An Empirical Investigation of Psychophysiological Characteristics and Psychological Variables in Information Systems Human Factors Research

Description: The purpose of this study was to test the comparability of several psychological instruments commonly used in Information Systems (IS) cognitive style research. The objective was to determine the limitations of: existing instruments in IS cognitive style research. The motivation for this research was the inconclusive findings reported in IS human information processing research. The study used a repeated measures design. Each individual completed the following cognitive style and personality instruments; the Myers-Briggs Type Indicator, the Group Embedded-figures Test, the Learning Style Inventory, the Human Information Processing Survey, and the Torrance Tests of Creative Thinking (Figural Form A). The individual also completed a dichotic listening and tachistoscope task. Data was collected from business administration, BCIS, liberal arts majors, and IS professionals. The results of this study indicate IS researchers need to consider several factors in the use of these instruments. A direct relationship exists between cognitive ability and results on the GEFT. Cognitive ability should be considered a moderating variable in interpreting the results of the GEFT. Also, the hypothesis that the GEFT is a surrogate for analytical and low-analytical abilities is not supported by this study. Other reported results include the inappropriateness of using the TTCT with adult populations. Also, the MBTI appears to be an appropriate instrument for measuring cognitive styles in IS research. This study reported that gender is a moderating factor on the classification of MBTI types in that gender is not evenly divided among feeling and thinking types. This study reported no relationships between the cognitive style and personality instruments with the physiological measurements. The validity of the physiological measurements could be the underlying factor for not reporting any significant relationships. IS researchers will benefit from this study through an improved understanding of the appropriateness and applicability of these instruments. This benefits research through the ...
Date: December 1989
Creator: Corman, Lawrence S. (Lawrence Sanger)

The Organizational Consequences of Information Deployment

Description: This study investigates the influence that increasing end user autonomy has on organizational data models. The independence offered by microcomputer technology offers users increasing independence in their information-handling activities. As independence increases, uniformity of data models across the organization is theorized to diminish. The problem motivating this study is the potential for improper allocation of resources that may result from a misinterpretation of organizational data. This study suggests that the expanding use of microcomputers in the business setting will contribute to diversity of data models. This may eventually lead to confusion and even lack of confidence in the information produced.
Date: December 1991
Creator: Remington, William S. (William Seth)

An Empirical Investigation of Detail Design Tools and Cognitive Style of Software Developers

Description: The purpose of this study is to identify what detail design tools are more productive for the different types of professional software developers. By establishing a match between the detail design tool and the cognitive style of the professional programmer, the end product (Information Systems) should be of a higher quality. Two laboratory experiments were conducted. The first experiment was with professional Software Developers; the second one was with students. The dependant variables considered in this study were the number of semantic errors and the time required to complete a design task for conditional logic. The independent variables were the cognitive style of the subject, the complexity of the task, and the detail design tools. Decision trees, flowcharts and pseudocode were used as detailed design tools. Field dependence was the only dimension of cognitive style that was tested.
Date: May 1992
Creator: Flores-Rosales, Oscar

A Simulation Study Comparing Various Confidence Intervals for the Mean of Voucher Populations in Accounting

Description: This research examined the performance of three parametric methods for confidence intervals: the classical, the Bonferroni, and the bootstrap-t method, as applied to estimating the mean of voucher populations in accounting. Usually auditing populations do not follow standard models. The population for accounting audits generally is a nonstandard mixture distribution in which the audit data set contains a large number of zero values and a comparatively small number of nonzero errors. This study assumed a situation in which only overstatement errors exist. The nonzero errors were assumed to be normally, exponentially, and uniformly distributed. Five indicators of performance were used. The classical method was found to be unreliable. The Bonferroni method was conservative for all population conditions. The bootstrap-t method was excellent in terms of reliability, but the lower limit of the confidence intervals produced by this method was unstable for all population conditions. The classical method provided the shortest average width of the confidence intervals among the three methods. This study provided initial evidence as to how the parametric bootstrap-t method performs when applied to the nonstandard distribution of audit populations of line items. Further research should provide a reliable confidence interval for a wider variety of accounting populations.
Date: December 1992
Creator: Lee, Ihn Shik

The Fixed v. Variable Sampling Interval Shewhart X-Bar Control Chart in the Presence of Positively Autocorrelated Data

Description: This study uses simulation to examine differences between fixed sampling interval (FSI) and variable sampling interval (VSI) Shewhart X-bar control charts for processes that produce positively autocorrelated data. The influence of sample size (1 and 5), autocorrelation parameter, shift in process mean, and length of time between samples is investigated by comparing average time (ATS) and average number of samples (ANSS) to produce an out of control signal for FSI and VSI Shewhart X-bar charts. These comparisons are conducted in two ways: control chart limits pre-set at ±3σ_x / √n and limits computed from the sampling process. Proper interpretation of the Shewhart X-bar chart requires the assumption that observations are statistically independent; however, process data are often autocorrelated over time. Results of this study indicate that increasing the time between samples decreases the effect of positive autocorrelation between samples. Thus, with sufficient time between samples the assumption of independence is essentially not violated. Samples of size 5 produce a faster signal than samples of size 1 with both the FSI and VSI Shewhart X-bar chart when positive autocorrelation is present. However, samples of size 5 require the same time when the data are independent, indicating that this effect is a result of autocorrelation. This research determined that the VSI Shewhart X-bar chart signals increasingly faster than the corresponding FSI chart as the shift in the process mean increases. If the process is likely to exhibit a large shift in the mean, then the VSI technique is recommended. But the faster signaling time of the VSI chart is undesirable when the process is operating on target. However, if the control limits are estimated from process samples, results show that when the process is in control the ARL for the FSI and the ANSS for the VSI are approximately the same, and ...
Date: May 1993
Creator: Harvey, Martha M. (Martha Mattern)

Mathematical Programming Approaches to the Three-Group Classification Problem

Description: In the last twelve years there has been considerable research interest in mathematical programming approaches to the statistical classification problem, primarily because they are not based on the assumptions of the parametric methods (Fisher's linear discriminant function, Smith's quadratic discriminant function) for optimality. This dissertation focuses on the development of mathematical programming models for the three-group classification problem and examines the computational efficiency and classificatory performance of proposed and existing models. The classificatory performance of these models is compared with that of Fisher's linear discriminant function and Smith's quadratic discriminant function. Additionally, this dissertation investigates theoretical characteristics of mathematical programming models for the classification problem with three or more groups. A computationally efficient model for the three-group classification problem is developed. This model minimizes directly the number of misclassifications in the training sample. Furthermore, the classificatory performance of the proposed model is enhanced by the introduction of a two-phase algorithm. The same algorithm can be used to improve the classificatory performance of any interval-based mathematical programming model for the classification problem with three or more groups. A modification to improve the computational efficiency of an existing model is also proposed. In addition, a multiple-group extension of a mathematical programming model for the two-group classification problem is introduced. A simulation study on classificatory performance reveals that the proposed models yield lower misclassification rates than Fisher's linear discriminant function and Smith's quadratic discriminant function under certain data configurations. Data configurations, where the parametric methods outperform the proposed models, are also identified. A number of theoretical characteristics of mathematical programming models for the classification problem are identified. These include conditions for the existence of feasible solutions, as well as conditions for the avoidance of degenerate solutions. Additionally, conditions are identified that guarantee the classificatory non-inferiority of one model over another in the training ...
Date: August 1993
Creator: Loucopoulos, Constantine

Comparing the Powers of Several Proposed Tests for Testing the Equality of the Means of Two Populations When Some Data Are Missing

Description: In comparing the means .of two normally distributed populations with unknown variance, two tests very often used are: the two independent sample and the paired sample t tests. There is a possible gain in the power of the significance test by using the paired sample design instead of the two independent samples design.
Date: May 1994
Creator: Dunu, Emeka Samuel

The Effect of Certain Modifications to Mathematical Programming Models for the Two-Group Classification Problem

Description: This research examines certain modifications of the mathematical programming models to improve their classificatory performance. These modifications involve the inclusion of second-order terms and secondary goals in mathematical programming models. A Monte Carlo simulation study is conducted to investigate the performance of two standard parametric models and various mathematical programming models, including the MSD (minimize sum of deviations) model, the MIP (mixed integer programming) model and the hybrid linear programming model.
Date: May 1994
Creator: Wanarat, Pradit

Productivity Considerations for Online Help Systems

Description: The purpose of this study was to determine if task type, task complexity, and search mechanism would have a significant affect on task performance. The problem motivating this study is the potential for systems online help designers to construct systems that can improve the performance of computer users when they need help.
Date: May 1994
Creator: Shultz, Charles R. (Charles Richard)

The Risks and Effects of Outsourcing on the Information Systems Function and the Firm

Description: IS outsourcing, especially large-scale IS outsourcing, is a comparatively recent and rapidly growing IS phenomenon, but it is also an inherently risky activity. In an IS outsourcing arrangement, the outsourcing vendor accepts responsibility for IS resources and functions formerly controlled directly by the firm. This research examines IS outsourcing from two perspectives. (1) From an IS perspective, it examines the risk perceptions of IS managers of fourteen Fortune-500 firms who had recently conducted an outsourcing evaluation. (2) From a financial perspective, it examines the theoretical relationship of IS outsourcing with financial performance, and investigates the empirical effects of IS outsourcing on the firm's market value and market risk. This research views IS outsourcing as an independent variable whose effects on the firm may be measured as changes in security returns, changes in asset risk, changes in capital structure, and long-term changes in profitability. To accomplish this, it characterizes IS outsourcing as a sale-and-leaseback transaction.
Date: May 1994
Creator: Peak, Daniel Alan

Robustness of Parametric and Nonparametric Tests When Distances between Points Change on an Ordinal Measurement Scale

Description: The purpose of this research was to evaluate the effect on parametric and nonparametric tests using ordinal data when the distances between points changed on the measurement scale. The research examined the performance of Type I and Type II error rates using selected parametric and nonparametric tests.
Date: August 1994
Creator: Chen, Andrew H. (Andrew Hwa-Fen)

A Case Study of the Use of Activity-Based Analysis as an Information Resource Management Tool

Description: The purpose of the study was to investigate a modification of a managerial accounting technique, Activity-Based Costing (ABC), as a tool for addressing Information Resource Management (IRM) concerns within business processes. To indicate that ABC has been adapted for the IRM context, this study called the tool "Activity-Based Analysis" (ABA). ABA includes ABC's costing methodology as well as additional methods to address broader issues. The research method was a single-site case study at a property and casualty insurance company. The unit of analysis was a business process consisting of activities needed to provide claims handling services for workers' compensation insurance. Four questions guided the study: 1. Did ABA identify management information required to monitor process effectiveness and efficiency? 2. Did ABA support outsourcing decision making by identifying IRM cost components within business processes? 3. Did ABA identify information resources; that are sharable? 4. Did ABA identify differences between Company organizational characteristics andIRM department organizational characteristics?
Date: December 1994
Creator: Arnett, Charles A. (Charles Augustus)

Interactions of Presentation Formats and Decision-Maker Characteristics upon Multiple Decision-Making Tasks: an Experiment Using Multiple Cognitive Assessments

Description: Information systems research tends to ignore individual differences in users. This laboratory experiment sought to illuminate contributions of decision-makers' cognitive processes to decision outcome as reflected in four hypothesis sets: the impact of imagery preference and presentation format upon (HI) recall accuracy and upon hemispheric activation during (H2) encoding and (H3) recall, and (H4) to examine the relationship between hemispheric activation differences and accuracy differences. Point-value (specific values) and intraset-pattern (relationships between values) recall were considered. Thirty MBA students, grouped by imagery preference (cognitive style) as favoring verbal (textual) or visual (graphical) information presentation, performed computer-based recall tasks using tabular and graphical formats in a repeated measures design. Hemispheric activation (cognitive process) was assessed using ratios of EEG activity in six frequency bands captured from six pairs of homologous electrode sites during encoding and recall.
Date: December 1994
Creator: Henson, Kerry L. (Kerry Lynn)

The Relationships of Cross-Cultural Differences to the Values of Information Systems Professionals within the Context of Systems Development

Description: Several studies have suggested that the effect of cultural differences among Information Systems (IS) professionals from different nations on the development and implementation of IS could be important. However, IS research has generally not considered culture when investigating the process of systems development. This study examined the relationship between the cultural backgrounds of IS designers and their process-related values with a field survey in Singapore, Taiwan, the United Kingdom and the United States. Hofstede's (1980) value survey module (i.e., Power Distance (PDI), Uncertainty Avoidance (UAI), InDiVidualism (IDV) and MASculininity/femininity) and Kumar's (1984) process-related values (i.e., technical, economic, and socio-political) were utilized in the data collection. The hypotheses tested were: whether the IS professionals differed on (H.,) their cultural dimensions based on country of origin, (Hg) their process-related values based on country of origin, and (H3) whether a relationship between their cultural dimensions and their process-related values existed. The countries were significantly different on their PDI, UAI and MAS, but not on their IDV. They significantly differed on their technical and sociopolitical values but not on their economic values. IDV and MAS significantly correlated with the process-related values in Singapore, Taiwan and the United States. In the United Kingdom, UAI significantly correlated with socio-political values; and MAS significantly correlated with technical and socio-political values. In Taiwan, UAI significantly correlated with technical and economic values. PDI did not illustrate any significant correlation with the IS process-related values in all four countries. In Singapore and the United States, UAI did not significantly correlate with any of these values. The results provide evidence that IS professionals differ on most of their cultural dimensions and IS process-related values. While IDV and MAS could be useful for examining the relationship between culture and systems development, research involving PDI and UAI might be of questionable benefit.
Date: December 1995
Creator: Holmes, Monica C. (Monica Cynthia)

The Role of Workstation-Based Client/Server Systems in Changing Business Processes: a Multiple Case Study

Description: Although several studies question information technology's contribution to productivity, organizations continue to invest in client/server systems (CSSs) particularly as enablers of business process reengineering (BPR). These efforts may be wasted if they do not improve business processes. This study focused on business processes and investigated the role of workstation-based CSSs in changing business processes. A multiple case study of workstation-based CSS databases in three organizations was performed with the proposition that they moderate the relation between managerial action and changes within business processes. The research framework suggested that changes to business processes are achieved by reducing uncertainty. In order to measure change in business processes, this study categorized business process change into: (1) compressing sequential tasks across functions, (2) compressing tasks vertically within the managerial hierarchy, (3) eliminating slack resources, (4) reducing the distance between the point of decision and the point of information or eliminating intermediaries, (5) reconfiguring sequential processes to operate in parallel, and (6) linking parallel activities during the process. Data collected from questionnaires, interviews, and observations from three case studies were used to construct network diagrams, relationship matrices, reachability matrices, and task tables of business processes. The results of this research partially support the proposition that managerial action affects business process change by reducing uncertainty. This research suggests that changes in the use of workstation-based CSSs are related to changes in business processes. However, because ofthe small sample size, no finding was made regarding changes in the strength of that relationship. Therefore, within its limitations, this research (1) partially supports the proposition that CSSs moderate changes in business processes, (2) found that both favorable and unfavorable changes may result from using CSSs, (3) explains how business process change occurs, and (4) suggests new variables for measuring successful BPR.
Date: December 1995
Creator: Nik Hassan, Nik Rushdi

The Effects of Alternative Presentation Formats on Biases and Heuristics in Human Decision Making

Description: The purpose of this research was to determine whether changes in the presentation format of items in a computer display could be used to alter the impact of specific cognitive biases, and to add to the knowledge needed to construct theory-based guidelines for output design. The problem motivating this study is twofold. The first part of the problem is the sub-optimal decision making caused by the use of heuristics and their associated cognitive biases. The second part of the problem is the lack of a theoretical basis to guide the design of information presentation formats to counter the effects of such biases. An availability model of the impact of changes in presentation format on biases and heuristics was constructed based on the findings of a literature review. A six-part laboratory experiment was conducted utilizing a sample of 205 student subjects from the college of business. The independent variable was presentation format which was manipulated by altering the visual salience or visual recency of items of information in a visual computer display. The dependent variables included recall, perceived importance, and the subjects' responses to three judgment tasks. The results clearly demonstrate that changes in presentation format can be used to alter the impact of cognitive biases on human decision making. The results also provide support for the availability model, with the exception of the proposed influence of learning style. Learning style was found to have no significant impact on decision making whether alone or in combination with changes in presentation format. The results of this investigation demonstrate that by using our knowledge of cognitive processes (e.g., the visual salience effect, the visual recency effect, and the availability heuristic), presentation formats can be altered in order to moderate the effects of certain biases and heuristics in human decision making. An understanding of ...
Date: May 1996
Creator: Van Dyke, Thomas P. (Thomas Peter)

The Impact of Multimedia on Information Scanning Effectiveness: an Empirical Study in an Executive Support Systems Environment

Description: This study investigates the impact of multimedia on the effectiveness of information scanning. Information scanning is the act of seeking and receiving a wide variety of special information to develop a thorough understanding of the organization and the environment. The application domain of this study is Executive Support Systems. The experimental task is to identify potential threats and opportunities, a strategic information-scanning activity, based on the information stored in three ESS prototypes. Forty subjects from four organizations participated in the experiment. A random assignment process allocated them into three groups. The control group used the text-based ESS. The first experimental group used the visual multimedia ESS. The second experimental group used the audiovisual multimedia ESS. The experiment was carried out on the sites of the participating organizations. The investigator measured the effectiveness of information scanning based on the number of threats and opportunities each subject identifies. A close-ended questionnaire measured subjects' retention of information. The results of this study support the cognitive-fit theory. The findings indicate that multimedia is not an appropriate presentation format for analytical tasks. Subjects who use text-based ESS identify significantly more threats and opportunities than subjects who use audiovisual multimedia ESS. The cognitive style of subjects does not moderate the impact of multimedia. The results show that the use of multimedia does not necessarily improve retention of information. Further research is needed to determine the most effective combination of text, graphics, animation, video, and sound.
Date: May 1996
Creator: Huang, Hsin-Chih

An Investigation of the Productivity of Information System Helpdesk User Support Professsionals as Impacted by Their Communication Behavior : A Field Experiment

Description: This research conducted an interdisciplinary field experiment to identify relationships between productivity, user satisfaction and IS Helpdesk USP's use of effective communication behavior. An experimental group of Helpdesk USPs of a large retail organization were trained by communication professionals in communication effectiveness, with emphasis on the needs of the telephone environment.
Date: May 1996
Creator: Breshears, Robert Louis

Robustness of the One-Sample Kolmogorov Test to Sampling from a Finite Discrete Population

Description: One of the most useful and best known goodness of fit test is the Kolmogorov one-sample test. The assumptions for the Kolmogorov (one-sample test) test are: 1. A random sample; 2. A continuous random variable; 3. F(x) is a completely specified hypothesized cumulative distribution function. The Kolmogorov one-sample test has a wide range of applications. Knowing the effect fromusing the test when an assumption is not met is of practical importance. The purpose of this research is to analyze the robustness of the Kolmogorov one-sample test to sampling from a finite discrete distribution. The standard tables for the Kolmogorov test are derived based on sampling from a theoretical continuous distribution. As such, the theoretical distribution is infinite. The standard tables do not include a method or adjustment factor to estimate the effect on table values for statistical experiments where the sample stems from a finite discrete distribution without replacement. This research provides an extension of the Kolmogorov test when the hypothesized distribution function is finite and discrete, and the sampling distribution is based on sampling without replacement. An investigative study has been conducted to explore possible tendencies and relationships in the distribution of Dn when sampling with and without replacement for various parameter settings. In all, 96 sampling distributions were derived. Results show the standard Kolmogorov table values are conservative, particularly when the sample sizes are small or the sample represents 10% or more of the population.
Date: December 1996
Creator: Tucker, Joanne M. (Joanne Morris)

Computer-Supported Collaborative Work and Its Application to Software Engineering in a Case Environment

Description: This study investigated, in the context of a field-based case study, possibilities for formation of a synergistic union between CSCW and CASE tools. A major dimension of today's software challenge is in gearing up for large-scale system development necessitating large teams of systems engineers. The principal goal of this research was to advance the body of knowledge regarding the nature of collaborative technological support in the software development process. Specifically, the study was designed to evaluate the potential for using a CSCW tool as an effective front-end to a CASE tool in the furtherance of SDLC goals.
Date: May 1997
Creator: Bailey, Janet L.