A quiz consists of 10 multiple choice questions. Each question is marked either “right” or “wrong.” Each right answer gets 5 points, and 1 point is taken off for each wrong answer.

Problem A
The correlation between the number of right answers and the number of wrong answers is _________________.

Problem B
The correlation between the score on the test and the number of right answers is _________________.

Question

A quiz consists of 10 multiple choice questions. Each question is marked either “right” or “wrong.” Each right answer gets 5 points, and 1 point is taken off for each wrong answer.

 

Problem A
The correlation between the number of right answers and the number of wrong answers is _________________.


   
Problem B 
The correlation between the score on the test and the number of right answers is _________________.

agent0smith · Answer

A is negatively correlated - as the number of right answers increases, the number of wrong answers has to decrease, and vice versa.

B is positively correlated - as the number of right answers increases, the test score must increase, and vice versa.

agent0smith · Answer

Note that it's +EV to guess every single question on that kinda test (if it has five or less answer choices)... you have a 1/5 chance of gaining 5 points, and a 4/5 chance of losing 1 point. Your EV of guessing is +0.2 points.