Professor jones wants to study vocabulary growth in preschool children. he contacts all of his faculty colleagues who have children, and from this group, he assembles a sample of 20 faculty children ranging from two to five years of age. to test each child’s word knowledge, professor jones reads each child a list of simple words that he has gathered from children’s storybooks and records whether or not the child understands each word. he then uses the results to publish norms (standard or expected levels of achievement) for vocabulary mastery for each year from two to five years of age.
what's wrong with this study? a. no control groupb. biased or nonrepresentative samplec. interpreting a correlation as indicating cause and effectd. experimenter bias (experimenters' expectations influence the results)e. participant bias (participants' expectations influence the results)