Perceived Usefulness, Perceived Ease of Use, and User

Valid measurement scales for predicting user acceptance of computers are in short supply. Most subjective measures used in practice are unvalidated, and their relationship to system usage is unknown. The present research develops and validates new scales for two specific variables, perceived usefulness and perceived ease of use, which are hypothesized to be fundamental determinants of user acceptance. Definitions of these two variables were used to develop scale items that were pretested for content validity and then tested for reliability and construct validity in two studies involving a total of 152 users and four application programs. The measures were refined and streamlined, resulting in two six-item scales with reliabilities of .98 for usefulness and .94 for ease of use. The scales exhibited hgih convergent, discriminant, and factorial validity. Perceived usefulness was significnatly correlated with both self-reported current usage r = .63, Study 1) and self-predicted future usage r = .85, Study 2). Perceived ease of use was also significantly correlated with current usage r = .45, Study 1) and future usage r = .59, Study 2). In both studies, usefulness had a signficnatly greater correaltion with usage behavior than did ease of use. Regression analyses suggest that perceived ease of use may actually be a causal antecdent to perceived usefulness, as opposed to a parallel, direct determinant of system usage. Implications are drawn for future research on user acceptance.

Perceived usefulness, perceived ease of use, and user acceptance of information technology

From the Publisher:
Written by the author of the best-selling HyperText & HyperMedia, this book provides an excellent guide to the methods of usability engineering. Special features: emphasizes cost-effective methods that will help developers improve their user interfaces immediately, shows you how to avoid the four most frequently listed reasons for delay in software projects, provides step-by-step information about which methods to use at various stages during the development life cycle, and offers information on the unique issues relating to informational usability. You do not need to have previous knowledge of usability to implement the methods provided, yet all of the latest research is covered.

Usability Engineering

This article describes recent research in subjective usability measurement at IBM, focused on evaluating the psychometric properties of questionnaires designed for use in scenario‐based usability evaluation The questionnaires address evaluation at both a global overall system level and at a more detailed scenario level The primary goals of this article are to (a) discuss the psychometric characteristics of IBM questionnaires that measure user satisfaction with computer system usability, and (b) provide the questionnaires, with administration and scoring instructions For scenario‐level measurement, the 3‐item After‐Scenario Questionnaire (ASQ) has excellent internal consistency, with coefficient alphas across a set of scenarios ranging from 90 to 96 For more global assessment, the Post‐Study System Usability Questionnaire (PSSUQ) also has excellent internal consistency, with an overall coefficient alpha of 97 Preliminary principal factor analysis of 48 PSSUQ questionnaires suggested the presence of

IBM computer usability satisfaction questionnaires: psychometric evaluation and instructions for use

Microcomputer playfulness: development of a measure with workplace implications

This study is a part of a research effort to develop the Questionnaire for User Interface Satisfaction (QUIS). Participants, 150 PC user group members, rated familiar software products. Two pairs of software categories were compared: 1) software that was liked and disliked, and 2) a standard command line system (CLS) and a menu driven application (MDA). The reliability of the questionnaire was high, Cronbach's alpha=.94. The overall reaction ratings yielded significantly higher ratings for liked software and MDA over disliked software and a CLS, respectively. Frequent and sophisticated PC users rated MDA more satisfying, powerful and flexible than CLS. Future applications of the QUIS on computers are discussed.

Development of an instrument measuring user satisfaction of the human-computer interface

Search processes in a hierarchical menu selection system were investigated in a study that varied the structure of the tree. A hierarchical data base was composed of 256 gift items grouped into different clusters and presented using menus. Depth of the tree was held constant while breadth varied with level. Five structures were explored with the following number of alternatives at each of four levels: constant (4 × 4 × 4 × 4), decreasing (8 × 8 × 2 × 2), increasing (2 × 2 × 8 × 8), concave (8 × 2 × 2 × 8), and convex (2 × 8 × 8 × 2). Subjects searched for either specifically named gifts (explicit targets) or gifts appropriate for a scenario situation (scenario targets). In general, explicit targets took less time to find and fewer frames to traverse than for scenario targets. For explicit targets, the increasing menu was slightly superior to the rest. Search time was about the same across the five tree structures for explicit targets, but differed greatly for scenario targets. The concave and inc...

The effect of tree structure on search in a hierarchical menu selection system

Menu selection in human/computer interaction is a metaphor of the restaurant menu. Although menu selection is widely used, its scope is currently limited, ill-defined, and information lean. A comparison of the restaurant menu and the computer menu reveal three avenues of improvement in menu systems. The correspondence of elements and features between restaurant and computer menus suggests that this powerful metaphor should be more fully developed. Second, there are a number of advantages of dynamic computer menus over static listings common to restaurants. Finally, restaurant menus currently have the advantage of breadth, richness, and graphic layout as well as a natural support system (the server) that is unparalleled in current computer applications. An analysis of deficiences in computer menus should prove invaluable in developing the next generation of menu selection techniques.

John P. Chin

Papers

Development of an instrument measuring user satisfaction of the human-computer interface

The effect of tree structure on search in a hierarchical menu selection system

The menu metaphor: food for thought