Author Question: Z-scores are useful because a) z-scores indicate a person's standing as compared to the group ... (Read 113 times)

hbsimmons88 · **on:** Jun 19, 2018

Z-scores are useful because

a) z-scores indicate a person's standing as compared to the group mean
b) z-scores can be converted to percentiles (assuming a relatively normal distribution)
c) z-scores are usually positive
d) both a and b

Question 2

Item difficulty refers to

a) item complexity
b) item obscurity
c) the number of people who answer an item correctly
d) all of the above