A Common Technique in the Field of Testing Is to Design

Essay

A common technique in the field of testing is to design the test so that it will have a mean of 50 and a standard deviation of 10. Examples are the MMPI (Minnesota Multiphasic Personality Inventory), CPI (California Personality Inventory), and the Tennessee Self-Concept Scale. (Perhaps when you become a famous test maker, you'll name your test after your school.)
a. The manual for the MMPI says that there is clinical significance to scores that are two standard deviations above the mean. From a thousand persons how many would be expected to get a clinical label?
b. What proportion would be expected to score 68 and above?
c. What proportion would be expected to score between 53 and 63?
d. What score separates out the lowest one-fifth?