Question 8 A researcher knows that in spite of the yellow flashing lights and signs announcing “school zone, 20 mph”, drivers in front of Elementary School B proceed at a mean speed of 22 mph. The he

Question 8 

A researcher knows that in spite of the yellow flashing lights and signs announcing “school zone, 20 mph”, drivers in front of Elementary School B proceed at a mean speed of 22 mph. The head of the Police Department’s Traffic Control Division hypothesizes that having an adult wearing a florescent orange & green vest at the crosswalks in front of School B will decrease the traffic speed from the current mean of 22 mph during critical times. Thus, the comparison mean is = 22 mph. A sample of n = 10 vehicles driving in front of School B is drawn when the orange lights are flashing AND an adult in florescent clothing is at the crosswalk. The Traffic Division’s head finds the following traffic speeds:

The speeds (mph) for this sample of ten cars were: 18, 25, 22, 17, 19, 23, 25, 19, 24, 17

With = .05, determine the critical value of z* , t*, or r* that needs to be employed here. The value is:

A.  .707

B.  1.833 

C. 1.96

D.  2.228 

E. 2.292

 F. the correct value of z* , t*, or r* is not listed in alternatives "a" through "e"

Question 9 

Dr. Mindfog, is a drug researcher interested in investigating the mind-altering effects of two very potent drugs, scotch and tequila. Specifically, Dr. Mindfog wonders, “Is there a difference between the two drugs in their mind-altering effects?” Wishing to minimize and effects due to physical differences in groups of subjects, he selects ten adult twin pairs to participate in his study (five mail twin pairs and five female twin pairs, obviously matched). One member of each twin pair is randomly assigned to one of two groups, such that one member of a twin pair is in the “scotch” group and the other member of the twin pair is in the “tequila” group. Then, using the famous Olson Mind Dazedness Test (OMDT) he measures each participant’s dazedness after self-administering three ounces of the drug within an hour’s time. Below are the dazedness scores of Dr. Mindfog’s experiment -- the higher the score, the more dazed the participant.

Twin Pairs                  Group 1      Group 2

                                    Scotch        Tequila

                  Dazedness Scores      Dazedness Scores 

 Bob & Bubba                7                9 

Fred & Frank                 4                 4 

Tim & Tom                    6                 5 

Mary & Madeline         5                 8 

Elvira & Evelyn             4                 3 

Juan & Jaime              4                 8 

Charla & Carla             9                10 

Jim & John                   8                 9

 Cindy & Sandy            5                  8

 Margaret & Marlene   3                  4

With = .05, determine the critical value of z* , t*, or r* that needs to be employed here. The value is:

A. .632 

B. 2.228 

C. 2.262 

D. 2.580 

E. 2.718

F.  the correct value of z* , t*, or r* is not listed in alternatives "a" through "e"

Question 10 

A researcher has a questionnaire that measures how conservative or liberal one’s political attitudes are and speculated that in person’s over the age of 65 years there is a direct relationship between one’s political attitude and one’s support of the death penalty for persons convicted of murder. Namely, the researcher hypothesizes that the more politically conservative senior adults will be more supportive of the death penalty. To test this hypothesis the researcher distributes two questionnaires to seniors, one about political attitudes where low scores indicate that the person has liberal attitudes and high scores indicate conservatism, and the other questionnaire measured support of the death penalty, where high scores indicate more support of the death penalty.

Subjects’  Political Attitude  Support ofNames       Variable 1             Death Penalty

                                                 Variable 2

Mat                   11                         14 

Mary                  6                           7 

Betty                16                         15

 Janet               4                            7 

Nick                  1                            3 

Tina                 10                           9 

Ken                    5                           9 

Dan                   3                            8 

Debbie            12                           9

 Megan            7                            6 

Frank               11                         13

With = .05, complete step 4 of the hypothesis testing procedure, what decision and conclusion should the researcher make?

A. The researcher should retain H0 and conclude that there is a direct relationship between political conservatism and support of the death penalty in senior adults 

B. The researcher should reject H0 and conclude that there is a direct relationship between political conservatism and support of the death penalty in senior adults 

C. The researcher should reject H0 and conclude that the mean of seniors' political conservatism is not different from the mean of his/her support of the death penalty 

D. The researcher should reject H0 and conclude political conservatism causes one to support the death penalty with more enthusiasm 

E. The researcher should reject H0 and conclude that there is negative relationship between political conservatism and support of the death penalty in senior adults

Question 11 

A psychopharmacologist (a psycholgist interested in the effects of drugs and physiology) is interested in determining the effects of caffeine (from coffee) on exam performance. Twenty students from a large introductory psychology class volunteered to participate in the study; all were dedicated coffee drinkers and all drank caffeinated coffee. The volunteers were then randomly divided into two groups such that there were ten students in each group. One group of 10 students was asked to study the exam material while drinking their normal doses of coffee, and to take the exam while drinking their normal doses of coffee before the test. This group is called the “Coffee with Test” group.

The second group of 10 students was asked to study the exam material while drinking their normal doses of coffee, but to take the exam without having consumed coffee for at the least 3 hours beforehand. This group is called the “No-Coffee with Test” group. One student from the “No-Coffee with Test” group became ill and was unable to sit for the exam. The researcher recorded the number of correct responses on the exam. One could get up to 15 items correct on the exam. The scores are below.

Coffee with Test                 No-Coffee with Test (Number Correct(Number Correct)                 Group 1                                  Group 2 2                                              8

 7                                            10 

12                                           14 

9                                              12

 9                                             9

 5                                             9 

6                                             13 

14                                           8 

6                                            12

 7                                           11  

Which of the following are the correct statements of the null and alternate hypotheses, H0 and HA ? H0: µ1 = µ2 and HA: µ1 µ2 

A. H0: µ1 µ2 and HA: µ1 = µ2

B.  H0: µ1 > µ2 and HA: µ1 µ2

C.  H0: µ1 µ2 and HA: µ1 > µ2 

D. H0: µ1 < µ2 and HA: µ1 µ2

E. H0: µ1 µ2 and HA: µ1 < µ2

F.  H0: p>0 and HA: < 0

G.  H0: p<0 and HA: > 0

H.  H0: p= 0 and HA: 0

Question 12 

 For a population with = 30 and = 8, find the X value that corresponds to z = 1.25[Round to the nearest hundredths place if a decimal. If your calculated value is not identical to one of the values below, but within plus or minus 0.99 of an answer below, assume it's a rounding error and select the answer that is closest to your calculated value.] 

A.  X = 10

B.  X = 20

C.  X = 25 

D. X = 40

E.  the correct value of X is not listed in alternatives "a" through "d", even when taking into consideration a rounding error of plus or minus 0.99.

Question 13 

A mathematics professor is interested in increasing the mathematical ability of college students in remedial math classes. The professor obtains a random sample of ten students enrolled in remedial math this semester and begins the semester teaching these ten students using the new “Skills Building Program” (SBP) that the professor devised. The final exam these ten students are given is the same final exam the professor has used for the past 15 semesters, where the mean score is 12 and the standard deviation is 4 across these previous 15 semesters (μ = 12 and σ = 4). High scores on this final indicate better mathematical performance. Test the professor’s hypothesis that the new SBP method improves scores on the final exam (and hence increases mathematical ability).

Final exam scores of students with new SBP method: 12, 10, 14, 13, 17, 12, 13, 17, 13, 15

With = .01, complete step 4 of the hypothesis testing procedure, what decision and conclusion should the researcher make?

A. The researcher should retain H0 and conclude the new SBP method improves scores on the final 

B. The researcher should retain H0 and conclude the new SBP method does not improve scores on the final

C.  The researcher should reject H0 and conclude the new SBP method improves scores on the final 

D. The researcher should reject H0 and conclude the high scores on the SBP are directly related to high scores on the final 

E. The researcher should retain H0 and conclude the new SBP method improves scores on the final

Question 14 

 Given a population of scores (items correct) on recent midterm exam in a Political Science course, you know that the data form a normal distribution with a mean of µ = 85 and a standard deviation of = 14, if someone's score had been converted to a z score, and that z score is -.5, how many items did that person get correct on the psychology test? [Round to the nearest hundredths place if a decimal. If your calculated value is not identical to one of the values below, but within plus or minus 0.99 of an answer below, assume it's a rounding error and select the answer that is closest to your calculated value.] 

A. 66 

B. 71 

C. 74 

D. 78 

E. the correct value is not listed in alternatives "a" through "d", even when taking into consideration a rounding error of plus or minus 0.99.