A Psychologist Who Taught the Introductory Psychology Course Always Gave $\Sigma$

Essay

A psychologist who taught the introductory psychology course always gave her class a "misinformation test"on the first day of class. Her test contained some commonly held incorrect beliefs about psychology. Over the years the mean number of errors on this test had been 21.50. The data for this year follow. Analyze the data with a t test, calculate the effect size index, and write a conclusion. $\Sigma$ X = 198 $\Sigma$ X² = 4700 N = 11