One possibility is that simply encouraging workers to spend more time writing their summaries improved performance, but fitting a linear model we find the correlation coefficient between time and F 1 is −0.06, indicating no linear correlation between time and accuracy across conditions.
table 1: Performance for a range of metrics (defined in § 4.4) as the number of targeted information units and the condition vary (b: Baseline, h: Highlight, p: Pin-Refine).