Identify the threat to internal validity in each of the following:
a. Some researchers who were given rats to train were told incorrectly that the rats had been bred for intelligence; other researchers were told that their rats were especially dull. The experimenters who had the "smart" rats reported faster learning than did the experimenters with the "dull" rats.
b. After the first exam, a professor divided his statistics class into high performers and low performers. The low performers were invited to attend special tutoring sessions where the professor not only reviewed lecture material but also discussed how to take notes and how to study for a statistics test. On the second test, the professor found that the students who received the tutoring improved considerably. The professor concluded that the tutoring sessions were effective in improving the test performance of those students.
c. A researcher divided people attending a weight control clinic into two groups. Both groups were given the same diet to follow, but the experimental group was also asked to keep a record of everything they ate, to weigh all the food in grams, and to count the calories. At the end of the study, the researcher found that the experimental group had lost more weight. The researcher concluded that the experimental treatment was more effective than diet alone.
a. Experimenter effect
b. Regression; Hawthorne effect
c. Experimental mortality may account for the finding. Because of the greater demands in the experimental group, not all subjects stayed in the program. Only those who were highly motivated to lose weight persisted in the program and were present for the post-treatment.
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The pages glued to the inside front and back boards of the cover of a book are called ________.
What will be an ideal response?
Children may be cognitively impaired by genetics, the health and habits of the mother, and the environment after the child is born
a. True b. False
Which of the following is the first step in implementing a changing criterion design?
a. determine the target criterion for acceptable performance b. determine the average performance of the student during baseline c. determine the number of data points required for each phase d. determine interim levels of performance
Karl is running for president of the student body at Pineridge High School. One of his opponents is a very popular student named Deshawn. Karl's election assembly speech was filled with derogatory and obscene language directed at his rival. He concluded his speech by unfurling a banner that said, Don't vote for Deshawn. He's Gay! When the principal suspended Karl, his father threatened a lawsuit
alleging that his son was being denied freedom of expression. Which of the following reflects the opinion of the U.S. Supreme Court on this issue? A) The First Amendment ensures Karl's freedom of speech and protects him from suspension. B) If Deshawn is gay, then Karl is telling the truth and cannot be disciplined. C) The school may discipline Karl for using obscene and derogatory language in a student assembly. D) The school cannot discipline Karl for using obscene and derogatory language in a student assembly.