Question 3. [ 14 marks ] [ First half of Chapter 8] Computer output from SPSS for use in Question 3 (d) Researchers at the University of Utah asked 64 student volunteers to use a machine that simulated car driving conditions. A light in the simulator would randomly flash red or green and the students were Choose from EITHER Independent Samples Test instructed to press a brake button as soon as possible when they detected the red flashes. For each OR Paired Samples Test student, the machine would calculate an overall reaction time' in milliseconds by averaging all their individual reaction times. Before using the simulator, the students were randomly assigned to either a cell phone group or a control group. The 32 students in the cell phone group conducted a conversation on a cell phone while using the simulator whereas the 32 students in the control group did not use a cell phone. The data are displayed below: Cell phone group Control group Group Statistics 636 626 543 456 557 642 610 485 Group N Mean Sid. Deviation Std. Error Mean 623 501 520 688 572 476 444 539 Reaction time Cell phone 32 585.18 19.646 15.847 615 574 609 679 457 586 626 523 Control 32 533.59 15.360 11.554 672 168 559 960 569 626 179 501 578 595 558 532 61 126 535 600 560 565 182 506 528 585 60 Independent Samples Test 542 525 573 527 487 Levene's Test 648 578 512 or Equality of 554 647 554 536 485 472 436 449 Variances t-test for Equality of Means 95% Confidence Interval For this study describe the [ 1 mark ] Sig- 12 Mean Std. Error of the Difference (i) units, Sig. tailed] Difference Difference Lower Upper (ii) treatment or factor of interest, Reaction Equal variances 077 783 2.631 011 assumed 51.594 19.612 12.390 864706 (iii) response. time Equal variances (b) Which form of statistical analysis should be used to investigate this data? not assumed 2.631 56.698 .011 51.594 19.612 12.317 90.871 For your answer, write down EITHER A two-independent sample t-test OR A paired data t-test [ 1 mark ] (c) (i) Use iNZight to draw the appropriate plot(s) for this study. [ 1 mark ] Note: Two files of the data table above are available on Canvas: Assignments > Assignment 3. You will need to choose EITHER ReactionTimeDatal.CSV Paired Samples Statistics OR ReactionTimeData2 . csv Mean N Std. Deviation Sld. Error Mean You may need to manipulate the data prior to drawing your plot(s). Pair 1 Cell phone 585.19 32 39.646 15.847 Hint: Consider how the data should be arranged given the answer you chose for (b).] Control 533.59 32 65.380 11.554 (ii) Comment on any features in the plot(s) in terms of the original story. [ 3 marks ] (d) Investigate whether, on average, the reaction times differ between the two groups. Use the appropriate f-test computer output from SPSS given to the right to conduct the f-test you chose in (b). Interpret your results. [ 6 marks ] Paired Samples Test Notes: Paired Differences (i) You must clearly show that you have followed Steps 1, 2, 3, 7, 9 and 10 in the "Step-by- 95% Confidence Interval of the Difference Step Guide to Performing a Hypothesis Test by Hand", Lecture Workbook, page 12, Sid Sid. Error Sig. (2 Chapter 7. Steps 4, 5, 6, and & are replaced by the computer output from SPSS given to Mean Deviation Mean Lower Upper di tailed) the right. Pair 1 Cell phone - Control 51.594 117.109 20.702 9.372 93.816 2.492 31 .018 (ii) Refer to the instructions on Page 1 of this assignment: "Hypothesis tests in this assignment". (e) Comment on the validity of the /-procedures conducted in (d) by briefly discussing each assumption in terms of the original story. [2 marks ]