Toshihisa Doi

A proposal of a user-interface index that corresponds with mental model structural elements

The objective of this research is to propose a user-interface design index that corresponds with mental model structural elements. A total of 35 user-interface design indexes were extracted from previous design related rules and design guidelines that pertain to design indexes. Next, the user-interface design indexes were linked to the mental model structural elements and a formal concept analysis was done in order to determine the relationship between them. The mental model structural elements were classified and structured according to human information processing, functional and structural models. Finally, we describe how designers can easily construct user-interface designs based mainly on the user-interface design index and mental model structural elements.

Which Design Seems Easy to Use? An Analysis of Individual Differences in Mental Models

We investigated whether the influence of age and individual differences in mental model construction level affect the evaluation of appearance and functionality when users select household electrical appliances based only on appearance. Results showed that older (age 66–80) adults emphasized usability more than young (age 20–34) adults did. Moreover, users with high proficiency in mental model construction focused more on usability than did those with less advanced mental models.

Verification of the questionnaire for the level of mental models building

In this study, the verification of the questionnaire for the level of mental model building was examined from viewpoint of the actual users’ operation. The user testing is conducted to grasp the level of mental model building. The validity of the questionnaire was investigated in terms of (a) operation time of the digital camera, (b) operation errors of the digital camera and (c) Structural model / Functional mode (the test result for measurement the level of mental model building after the operation). Then, the correlation between the score of the user testing and the questionnaire score was calculated. As the result, the significant correlation is confirmed between each score and the questionnaire score. Then, we believed the proposed questionnaire can be measured the users’ mental model building level in the user-interfaces operation.

Structure of FUN factors in the interaction with products

In recent years interaction design has looked to questions of most typically positive emotions such as satisfaction, pleasure and delight. This study investigated the factors of FUN as joy and pleasure, which are created in interaction between human and products, and found their relationship. We aim for gaining useful information when we design products. First, the questionnaire regarding SCT (sentence completion test) were conducted and were analyzed by DEMATEL method (Decision MAking Trial & Evaluation Laboratory) As a result, it was found that the factors of FUN were clarified and examined the relationship.