Download Homework Assignment: Statistics and Hypothesis Testing and more Exercises Cognitive Psychology in PDF only on Docsity! Homework # 4 – Chapter 5 Name ______________________________________________ For the following questions, select the best answer. 1. Random _______ pertains to how a sample is drawn from a population? a. assignment b. selection c. statistics d. analyses e. number 2. Consider a typical (unbiased) die with each of the numbers 1-6 represented once. On a given roll, the probability of rolling a 1 is about a. .05 b. 1.0 c. .167 d. .200 e. .283 3. If one completed 1000 trials with the die, we would expect ______ of these trials to come up with a 4. a. 50 b. 1000 c. 167 d. 200 e. 283 4. Suppose that one flips an unbiased coin 100 times, and heads comes up on 45 of these trials. If we flip the coin an additional 100 times, we would expect heads to come up on _______ of these trials. a. 45 b. 50 c. 55 5. A researcher hypothesizes that rats raised in enriched environments (i.e., those with large cages, running wheels, etc.) are more intelligent than rats raised in deprived environments (i.e., those with the bare necessities). To test this hypothesis, (s)he assigns rats randomly to an environmental condition (deprived vs. enriched), and later measures how quickly each rat “learns” a new maze. According to the null hypothesis, rats in the enriched group should learn the new maze _____ than the rats in the deprived group. a. faster b. no faster 6. If the results of a study show that the difference between the means of two groups is not significant, then we a. accept the null hypothesis. b. reject the null hypothesis. c. fail to reject the null hypothesis. 7. A ______ error occurs when one erroneously rejects the null hypothesis. a. Type I b. Type II c. Type III d. Type IV 8. From an X-ray, a phyisican determines that a tumor is present when actually there is no tumor. This “false positive” is essentially the same as a ______ error. a. Type I b. Type II c. Type III d. Type IV 9. A researcher does not find a significant difference in reaction time between a group of individuals who consumed alcohol and a control group. (S)he concludes that alcohol does not slow down reaction time. The researcher probably made a _____ error. a. Type I b. Type II c. Type III d. Type IV 10. External validity is threatened by a(n) a. unbiased sample. b. biased sample. c. random selection. d. random assignment. Docsity.com
