Host: JAPANESE SOCIETY FOR THE SCIENCE OF DESIGN
With a result of this study until now, Characters in using cellular phones were classified with each user group and the difference in the attribute such as time, place and more by the quantification-3. But, the result has vagueness and contradiction, and the characters tend to overlap in different user groups. So in this time, the classification of the using was done by Rough Sets to know the character of details of each user group. Each attribute in using was applied to condition attributes, and each function of cellular phones was applied to decision attributes, we got combination of the attribute, which decided the characteristic of the each group. For example, though it was the same "E-mail" function, a user group exchanges much of short texts at one time, and another group exchange only one of long text at one time. Those characters are most important for each user group. So, the detailed characteristic in using could be described.
