Proportion accuracy

#1
Hello, i need some help with this variables - I can't understand how it was calculated
from article <<. Accuracy at the trial level was a binary variable (incorrect answer = 0; correct answer = 1), indicating whether the participant choose the right applicant.
We aggregated accuracy across trials and used proportion correct. How can I calculate the proportion of correct choices?
In data set we have N= 119.

Also, for slope - this is defined as the mean subjective probability given that the categorical choice is correct minus the mean subjective probability given that the categorical judgment is incorrect. How in this case can I calculate slope?