noncontact sport athletes. The following table presents data similar to the resu

ID: 3309934 • Letter: N

Question

noncontact sport athletes. The following table presents data similar to the results obtained in the study Athle 13 10 12 Are the test scores significantly lower for the contact sport athletes than for the noncontact athletes? Use a one-tailed test with -.05. a. b. Compute the value for r (percentage of variance accounted for) for these data. 5. Recent research has shown that creative people are more likely to cheat than their less- creative counterparts (Gino & Ariely, 2011). Participants in the study first completed creativity assessment questionnaires and then returned to the lab several days later for a series of tasks. One task was a multiple-choice general knowledge test for which the participants circled their answers on the test sheet. Afterward, they were asked to transfer their answers to a bubble sheet for computer scoring. However, the experimenter admined that the wrong bubble sheet had been copied so that the correct answers were still faintly visible. Thus, the participants had an opportunity to cheat and inflate their test scores. Higher scores were valuable because participants were paid based on the aumber of correct answers. However, the rescarchers had secretly coded the original tests and the bubble sheets so that they could measure the degree of cheating for each participant. Assuming that the participants were divided into two groups based on their creativity scores. the following data are similar to the cheating scores obtained in the study High-Creativity Low-Creativity M-7.41 SS- 7495 n 27 M- 4.78 SS 830 a. Use a one-tailed test with 05 to determine whether these data are sufficient to conclude that high-creativity people are more likely to cheat than people with lower levels of creativity b. Compute Cohen's d to measure the size of the effect When you get a surprisingly low price on a product do you assume that you got a really good deal or that you bought a low-quality product? Research indicates that you are more likely to associate low price and low quality if someone else makes the purchase rather than yourself Yan & Sengupta, 2011 ). In a similar study, n 16 participants were asked to rate the quality of low-priced items under two scenarios: purchased by a friend or purchased yourself. The results produced a mean difference of Mp-2.6 and SS- 135 with self-purchases rated higher 6.

Explanation / Answer

Part (a)

Back-up Theory

Let X = test scores of non-contract athletes.

Y = test scores of contract athletes.

Then, X ~ N(µ1, 12) and Y ~ N(µ2, 22), where 12 = 22 = 2, say and 2 is unknown.

Claim:

Test scores are significantly lower for contract athletes than for non-contract athletes; i.e.,

µ2 < µ1

Hypotheses:

Null: H0: µ1 = µ2 Vs Alternative: HA: µ1 > µ2

Test Statistic:

t = (Xbar - Ybar)/{s(2/n)} where

s2 = (s12 + s22)/2;

Xbar and Ybar are sample averages and s1, s2 are sample standard deviations based on n observations each on X and Y.

Calculations

Summary of Excel calculations is given below:

n =

Xbar =

9.25

Ybar =

s1 =

2.251983

s2 =

2.828427

s^2 =

6.535714

s =

2.556504

tcal =

2.542534

0.05

tcrit =

1.76131

p-value =

0.011727

Distribution, Critical Value and p-value:

Under H0, t ~ t2n - 2. Hence, for level of significance %, Critical Value = upper % point of t2n - 2 and p-value = P(t2n - 2 > tcal).

Using Excel Functions, the above are found to be as given above.

Decision Criterion (Rejection Region):

Reject H0 if tcal > tcrit or p-value <

Decision:

Since tcal > tcrit, H0 is rejected. Since p-value < , H0 is rejected.

Conclusion:

There is sufficient evidence to suggest that the claim is valid. i.e.,

Test scores are significantly lower for contract athletes than for non-contract athletes ANSWER

Part (b)

r2 = 0.1132 ANSWER

n =