(Prob set ch11Q9). Please answer all questions. Please ensure that you go up to three decimals places for numerical values.

9. Measures of effect size for the repeated-measures t Previous studies have shown that playing video games can increase visual perception abilities on tasks presented in the gaming zone of the screen (within 5 degrees of the center). A graduate student is interested in whether playing video games increases peripheral visual perception abilities, or decreases attention to peripheral regions because of foous on the gaming zone. For her study, she selects a random sample of 81 adults, The subjects complete a difficult spatial perception task to determine baseline levels of their abilities. After playing an action video game (a first-person combat simulation) for 1 hour a day over 10 days, they complete the difficult perception task for a second time. Before playing the action video game, the mean score in their accuracy on the spatial task was 0.31. After playing the action video game, the mean score was 0.04 higher. The graduate student has no presuppos ns about whether playing video games increases peripheral visual perception abilities, or decreases attention to peripheral regions because of focus on the gaming zone, so she formulates the null and alternative hypotheses act HO E UD - 0 HI :UD + 0 Assume that the data satisfy al lculates the following statistics for her hypothesis test: Mean difference (MD) 0,04 Estimated population standard deviation of the differences (s) 0.08 Estimated standard error of the mean differences (5MD) 0.0089 Degrees of freedom (df) 80 The t statistic 4.49 The critical values of t when a = .05 +1.990 Notice that since the t statistic (4.49) is A 95% confidence interval for the Use Cohen's d to calculate size Use ra to calculate the effect size. The re is perception is explained by whether it was measured before or after 10. Advantages and disadvantages of the related-samples desig Disadvantages of using a related sample (either one sample of participants independent samples include which of the following? Check all that apply Related samples (specifically, one sample of participants with repeated measures) between one measurement and the next might be attributable to the order in which treatment effect. Related samples (specifically, one sample of participar learn from their first measurement and therefore do better on their se A related-samples design reduces or eliminates problems caused by individual differences such as age, IQ. gender. WA study that uses related samples to compare two drugs (specifically, one s of participan bested measures) can ha carryover and/or order effect such that the effects of the drug taken before the first measurement may not wear off before the second measurement