Proposal of a skill level index based on user's thinking time

Abstract

The time required to accomplish a task is the most common index of skill level. A learning curve that expresses the deductive process in relation to time needed is widely used. However, it does not always provide an accurate picture, because it cannot be used for a task that has an irregular form. And it cannot perform evaluations in real time during user operation. Moreover, because it is influenced by an error factor, it lacks precision. Studies have already been undertaken on a basic user adaptive interface. However, to increase its effectiveness and enable it to provide more intelligent support, it is necessary to consider the user's skill level. Thus, a skill level index is provided based on the user's thinking time.To put it more concretely, the authors looked at the time interval between one operation and the next. Using a statistical technique, we evaluated the shll level quantitatively. Experiments with test subjects showed that the proposed index coincides well with the subjectivity of the experimenter and the working time. The features of this index are that it does not depend directly on the content of the task, but on the user's cognitive performance. Therefore, this index can be used for a task with an irregular form and will provide real-time evaluation by repeatedly gathering event data at regular intervals.

Pauses in man-machine interactions: a clue to users' skill levels and their user interface requirements

“…701 (see online version for colours) Figure 10 Mean values for operationIntervalVariance across the 15 trials. operationIntervalVariance is defi ned as the variance of the time intervals between consecutive operations in performing a task (Nakamura et al, 1996). The time between two subsequent activities is considered as pause.…”

“…However, there is inconsistency in using the term pause in the related literature. Some works, such as Santos and Badre (1994) and Nakamura et al (1996), have considered the time interval between every two subsequent actions as a pause and not the absolute motionless periods in which the users do not even move the mouse and no physical interaction takes place at all. On the other hand, there are research works, such as Reeder and Maxion (2006), that have considered only absolute motionless periods during the users' interactions as pauses.…”

“…They measured the pauses in subjects' interactions while performing a variety of partially-defi ned goal-oriented tasks. Nakamura et al (1996) found that the variance of the operation time interval is a useful index in determining the skill levels of users. They defi ned operation time interval as the time between the completion of one operation and the start of the next (i.e., the time interval between two consecutive operations).…”