• 23. In her prediction study of high school mathematics experiences and University
calculus performance, Kirby reported that number of courses taken was correlated r=.42
while the grades in high school mathematics courses was correlated r=.25 with university
grades. Given her findings, Kirby can conclude which of the following?
a. High school grades are a better predictor than are number of courses taken.
b. Both high school grades and number of courses taken are strong predictors.
c. Both high school grades and number of courses taken are weak predictors.
d. Number of courses taken are a better predictor than are high school grades.
24. Testing the statistical significance of a correlation requires knowledge of
a. mean, sample size, level of significance.
b. mean and level of significance.
c. level of significance and sample size.
d. sample size and mean.
• 25. In a prediction study of low achieving students academic motivation, Hillary was
surprised that achievement scores were not a significant predictor of motivation. Hillary’s
analysis is most likely is displaying
a. shrinkage.
b. attenuation.
c. standard variance.
d. restriction of range.
26. Attentuation refers to
a. stating there is not a relationship between two variables when there is one
b. lowered accuracy in a prediction equation when it is applied to a new sample.
c. combining many variables in order to predict the most amount of variance.
d. effects of unreliable instruments underestimating the correlation.
27. Shrinkage refers to
a. lowered accuracy in a prediction equation when it is applied to a new sample.
b. combining many variables in order to predict the most amount of variance.
c. effects of unreliable instruments underestimating the correlation.
d. a measure of the error found in a regression equation.
28. Errors in instrument reliability
a. do not effect interrelatedness of variables.
b. decrease the number of significant relationships found.
c. increase the number of significant relationships found.
d. may either increase of decrease the number of relationships between variables.
29. Data collection for types of correlation studies is generally
a. longer than most qualitative approaches.
b. shorter for prediction studies than for correlation studies.
c. longer than most types of quantitative research.
d. shorter than most types of quantitative research.