
48 N. Jiang
Figure 1. Completion Rate (CR) and Error Rate (ER).
Table 4. Correlation matrix (p< 0.01).
Errors
Completion (Task A) Play.com −.709
Amazon.co.uk −.388
Completion (Task B) Play.com −.346
Amazon.co.uk .153
onTask A as it reported much higher task completion rate with lower error rate than
the latter (82% with 51% vs. 16% and 68%), which is also in line with statistical
analysis. However, the two websites delivered very similar results on Task B which
cannot lead to a conclusion as the difference is only marginal (57% with 59% vs.
55% with 61%).
Relationships between metrics
A correlation matrix with the two metrics was generated by using the