PUT YOUR NAME Psy 210 Spring 2004 Tues March 2, 2004
ON THE BACK Quiz 2 Instructor: Kim Barchard
1. If income is positively skewed, which is largest, the median, mode, or mean? (2 marks)
a) median
b) mode
c) mean
2. Why do we use n-1 in the formula for the sample variance? (1 mark)
3. Two researchers are doing the same experiment at different universities. They have never
spoken to each other, and they do not know that the other person is doing the same research.
When conducting their studies, the researchers can either make good decisions based on their
data, or they can make mistakes. Let us imagine that the probability of a good decision is .95
and the probability of a mistake is .05. What is the probability that both researchers make
mistakes? You may solve this problem using any strategy you like, but be sure to show all
your work. (1 mark)
