- follow-up to [[220301_145044 user ECDFs#fact-checker CDFs 60 domains|fact-checker CDF pointwise proportion tests]]
## Threshold linear regressions (control for blocking)
For each quality value (`q: [0...99]`; x-axis), we fit a model (`y ~ condition[-0.5/0.5] * mean_t0C | block`) where we assign the user's outcome `y = 100` if the user's mean quality during the campaign is above `q` (otherwise `y = 0`).
- x-axis: each threshold value (one model per value)
- y-axis: regression coefficients estimate (95% CI)
- panels: different coefficients in the model
```r
# for each quality thresold q in 0 to 99
dt1[, y := ifelse(mean_t1 > q, 100, 0)]
m_temp <- feols(y ~ conditionC * mean_t0C | block, dt1[domain_type == "overall"])
```
- first panel (**condition coefficient**): When `q` is between 15 and 45, condition coefficient is positive: Being in the treatment (vs. control) group makes it more likely for users to be belong to the "higher-quality" (`y = 100`) group.
- second panel (**condition:mean_t0 interaction**): Condition coefficient depends on users' pre-campaign quality. The coefficient is more positive for those whose pre-campaign quality is lower (again, consistent with what we have found so far! see [[220303_135802 fact-checker analyses|fact-checker analyses]]).
![[dv_fc_thresholds_interact 5.png|800]]