Clustering students’ writing behaviors using keystroke logging: a learning analytic approach in EFL writing

Language Testing in Asia

Table 2 Process indicators weights and the explained proportion of variance for PCs

Process indicators	PC 1	PC 2	PC 3	PC 4
The geometric mean of within-word pauses	0.052	0.10	− 0.09	0.75
The geometric mean of before-word pauses	0.32	0.19	− 0.14	0.23
The geometric mean of before-sentence pauses	0.22	− 0.20	0.03	0.27
The longest pause	0.28	0.19	0.46	− 0.12
Location of the longest pause	− 0.12	− 0.29	− 0.09	0.28
Pause variance	0.41	0.02	0.34	− 0.06
Total pause time	0.36	0.30	− 0.15	− 0.008
Total active writing time	− 0.20	0.36	− 0.29	− 0.10
Total process time	0.27	0.38	− 0.22	− 0.03
Total words in main document	− 0.26	0.42	− 0.02	0.10
Mean word length	0.09	− 0.07	− 0.10	0.29
Mean typed in p-bursts	− 0.10	0.15	0.62	0.27
Total typed per minute	− 0.43	0.10	0.22	0.10
Total keystrokes	− 0.22	0.44	0.08	0.04
Explained variance proportion	0.30	0.26	0.11	0.09