onds. Three of the subjects in the latter group did not look at this area at all.

The first fixation times of the two groups were compared for the task-relevant areas in the dashboard. The bar chart labeled “Product Type By Market Size” was chosen as a task-relevant area because viewers needed to see this area to complete the task. The results (see Table 3) show viewers using the dashboard with no misuse of colors viewed this area much more quickly than the other group, indicating the contrasted areas indeed distracted the viewers who engaged in System 1 and System 2 processing, respectively.

The sample heat maps of two subjects (see Figure 4) reflect the analysis mentioned in Table 2 and Table 3. The bottom-left heat map in Figure 4 shows areas with contrasting colors attracted viewer’s attention, whereas the bottom-right heat map shows the focus was on the task-relevant areas (such as the chart title).

A fixation-sequence analysis was conducted to determine whether a viewer’s decision-making process involving the dashboard with misuse of colors was different from those viewing the dashboard with no such misuse. To do it, the dash-

Figure 3. Heat maps of a subject performing a task with overuse vs. no overuse of colors in dashboards.

(a) (b)

Figure 4. Heat maps of two subjects performing tasks with dashboards.

(a) (b)

Table 2. Analysis of fixation durations and counts for dashboards with misuse of colors.

Group Fixation duration (ms) t-stat p-value Fixation count t-stat p-value

Dashboard with misuse of colors

45176.69 2. 37 0.01* 159.43 1. 92 0.03*

Dashboard with no misuse of colors

26800.00 102.57

* significant at 0.05 level; ms = millisecond

Table 3. Analysis of the first fixation times for dashboards that misuse colors; similar results were obtained for the other task-non-relevant and -relevant areas between the two groups.

Group
First fixation time task
non-relevant area
(ms) t-stat p-value
First fixation
time-task-relevant
area (ms) t-stat p-value

Dashboard with misuse of colors

6205.31 7. 50 0.00* 13065.63 6. 76 0.00*

Dashboard with no misuse of colors

18127.09 7901.45

* significant at 0.05 level; ms = millisecond

Table 1. Analysis of fixation durations and counts for dashboards with overuse of colors.

Group Fixation duration (ms) t-stat p-value Fixation count t-stat p-value

Dashboard with overuse of colors

28313.71 2. 12 0.02* 107.78 2. 47 0.01*

Dashboard with no overuse of colors

22586.44 78. 25

* significant at 0.05 level; ms = millisecond