An educational psychologist is testing the discriminant validity of a new measure of numerical learning difficulties. he gives his measure to a group of students along with another measure of verbal learning difficulties, which he predicts should not be strongly related to numerical learning difficulties. which of the following correlations would the psychologist hope to find in order to establish discriminant validity?
a. r = 1.0
b. r = 0.83
c. r = −0.18
d. r = −1.0

Which of the following selections is least useful for supporting the claim that states intentionally built unequal school systems? question 1 options: the supreme court ruling in plessy v. ferguson (1896) wrote into law that america had two separate societies: one black and one white. it was very clear by the mid-1900s that southern states had expertly built separate educational systems. these schools, however, were never equal. states with laws keeping schools segregated never gave equal amounts of money to their black and white schools. ten years after brown, fewer than 10 percent of southern public schools had integrated. some areas did not comply at all.