Solved by verified expert:QUESTION 1Two researchers (A and B) compute a one-sample t test. For both tests, the mean difference between the sample and value stated in the null hypothesis is 5, but the standard error is smaller for Researcher A. Which test is more likely to result in a decision to reject the null hypothesis?a.The likelihood is the same for both researchers.b.Researcher B.c.Researcher A.d.There is not enough information to answer this question.10 points QUESTION 2A researcher selects a sample of 16 women and asks them to rate how important a sense of humor is in someone they want a long-term relationship with. She records scores averaging 1.6±0.8 (M±SD) on a rating scale from -3 (not important at all) to +3 (very important). Assuming that an average score of 0 is the null hypothesis, test whether or not women find this trait important at a .05 level of significance.a.Women did not find this trait to be important, p > .05.b.Women found this trait to be important, and this result was significant, t(16) = 8.00, p < .05.c.There is not enough information to answer this question.d.Women found this trait to be important, and this result was significant, t(15) = 8.00, p < .05.10 points QUESTION 3The t distribution is similar to the z distribution except:a.It is associated with greater variability.b.It is characterized by “thicker” tails compared with the z distribution.c.It is associated with scores being more likely in the tails of the distribution.d.All of the above.10 points QUESTION 4Two researchers (A and B) compute a two-independent sample t test. For both tests, the standard error is the same, but the mean difference between the groups is larger for Researcher A. Which test is more likely to result in a decision to reject the null hypothesis?a.There is not enough information to answer this question.b.Researcher A.c.Researcher B.d.The likelihood is the same for both researchers.10 points QUESTION 5As a requirement for the t test, researchers compute any type of t test with samples selected from populations in which:a.The population is the same size as the sample.b.The population size is very large.c.The population variance is known.d.The population variance is unknown.10 points QUESTION 6A researcher conducts a study and concludes that a new behavioral health treatment program significantly reduces one's risk for disease compared with risk levels in the general population (d = -0.64). Interpret the size of this effect.a.64% of the variability in risk level can be accounted for by the new treatment.b.Risk levels in the population shifted 0.64 standard deviations above the mean.c.Risk levels in the population shifted 0.64 standard deviations below the mean.d.64% of the new treatment can be accounted for by the risk levels.10 points QUESTION 7Which of the following summarizes a t test that was significant and associated with a large effect size?a.T(30) = 1.03, p < .05, d = .20.b.T(60) = 1.76, p < .05, d = .45.c.T(12) = 2.95, p < .05, d = .82.d.T(22) = 3.02, p < .05, d = .36.10 points QUESTION 8Is a one-sample t test reported differently for one-tailed and two-tailed tests?a.It depends on whether the results were significant.b.It can be reported differently when the effect size is large.c.Yes, only significant results for a two-tailed test are reported.d.No, the same values are reported.10 points QUESTION 9A researcher conducts two t tests. Test 1 is a one-tailed test with a smaller sample size at a .05 level of significance. Test 2 is a one-tailed test with a larger sample size at a .05 level of significance. What do you know about the critical values for each test?a.It depends; there is not enough information to answer this question.b.Test 2 is associated with smaller critical values.c.Each test is associated with the same critical values.d.Test 1 is associated with smaller critical values.10 points QUESTION 10Two researchers (A and B) compute a one-sample t test. For both tests, the standard error is the same, but the mean difference between the sample and value stated in the null hypothesis is smaller for Researcher A. Which test is more likely to result in a decision to reject the null hypothesis?a.Researcher A.b.The likelihood is the same for both researchers.c.Researcher B.d.There is not enough information to answer this question. cf_u06a1_onesample_t_test__confidenceintervals.doc Unformatted Attachment Preview PSYC4700 - Statistics for the Behavioral Sciences u06a1 – One-Sample t Tests, Independent Samples t Tests, and Confidence Intervals Complete the following problems within the Word document (do not submit other files). Show your work for problem sets that require calculations. Ensure that your answer to each problem is clearly visible. (You may want to highlight your answer or use a different type of color to set it apart.) Submit the document to your instructor by Sunday, 11:59 p.m. central time. Problem Set 6.1: One-Sample t Test Criterion: Hand calculate a one-sample t test. Data: Rex’s Flower Shop advertised freshly cut roses that last longer than other roses. The mean vase life for a rose is 8 days. The following is a sample of the vase life of 9 bouquets of roses from Rex’s Flower Shop: 8, 6, 12, 11, 8, 9, 14, 15, 10. Instruction: Complete the following: a. State the nondirectional hypothesis. b. State the critical t for α = .05 (two tails). c. Calculate t. Show your work. d. Answer: Is the vase life of Rex’s roses significantly different than the population mean? Explain. Remember, you must show all of your work to receive credit. Problem Set 6.2: One-Sample t Test in SPSS Criterion: Calculate a one-sample t test in SPSS. Data: Use the Rex’s Flower Shop data from problem set 6.1. Instruction: Complete the following: a. Enter the data from problem set 6.1 into SPSS and name the variable as Roses. b. In the Toolbar, click Analyze, select Compare Means, and then select One-Sample t Test. c. Select Roses, then click Arrow to send it over to the right side of the table. In the box labeled Test Value, enter 8. d. Click OK and copy and paste the output into the Word document. e. Compare your SPSS output to your hand calculations from Problem Set 6.1. Are they the same? (Assignment continues on next page.) 1 PSYC4700 - Statistics for the Behavioral Sciences Problem Set 6.3: Confidence Intervals Criterion: Calculate confidence intervals using SPSS. Data: Use the SPSS output from Problem Set 6.2 above. Instruction: Based on the SPSS output from Problem Set 6.2, including a test value (population mean) of 8, calculate the 95% confidence interval. Problem Set 6.4: Standard Error of the Difference Between the Means Criterion: Analyze the relationship between standard error and the difference between the means. Data: A researcher examines the results of two separate studies. In the first study, the difference between Group A and Group B is two points, but the standard error is large and the difference is not significant. In the second study, the difference between Group A and Group B is also two points, but the standard error is small and the difference is significant. Instruction: Answer this: What might be the reason for the difference in the standard error across the two studies? Problem Set 6.5: Independent Samples t Test in SPSS • Criterion: Calculate an independent samples t test in SPSS. • Data: Ms Z has two groups of band students. She asks Group 1 to use her new embouchure strengthening cream before practice and asks Group 2 to practice as usual. The groups practiced for the following number of minutes: o • Minutes of practice: ▪ Group 1: 55, 44, 62, 30, 78, 50, 52. ▪ Group 2: 31, 40, 53, 22, 41, 16, 33. Instruction: Complete the following steps: a. Open SPSS and create a New Dataset. b. Click the Variable View tab and type Groups in the Name column. Click on the gray box in the Values column. Value Labels window appears. Enter 1 in the Value area and enter Embouchure Cream in the Label area. Click Add. Now enter 2 in the Value area and enter No Cream in the Label area. Click Add. Click OK. The Variable View screen appears. c. In row two, enter Minutes in the Name column. d. Click Data View. (Assignment continues on next page.) 2 PSYC4700 - Statistics for the Behavioral Sciences e. Enter the minutes of practice data (e.g., 1 under Groups and 55 under Minutes; 2 under Groups and 31 under Minutes). f. In the Toolbar, click Analyze, select Compare Means, and then select Independent-Samples t Test. g. Select Minutes, then click Arrow to send it over to the Test Variable box. h. Select Groups and then click Arrow to send it over to the Grouping Variable box. i. Click Define Groups and enter 1 for Group 1 and enter 2 for Group 2. Click Continue. j. Click OK and then copy and paste the output to the Word document. Problem Set 6.6: Independent Samples t Test Criterion: Identify IV, DV, and hypotheses and evaluate the null hypothesis for an independent samples t test. Data: Use the information from Problem Set 6.5. Instruction: Complete the following: a. Identify the IV and DV in the study. b. State the null hypothesis and the directional (one-tailed) alternative hypothesis. c. Can you reject the null hypothesis at α = .05? Explain why or why not. 3 ... Purchase answer to see full attachment
