8:22 Done Output2 [Document4).pdf T-TEST PAIRS=day WITH night (PAIRED) /ES DISPLAY (TRUE) STANDARDIZER (SD) /CRITERIA=CI ( . 9500) /MISSING=ANALYSIS. T-Test [DataSet4] C: \\Users\\so152301\\Downloads\\ppcs_matched_pairs_for_chapter_11 . sav Paired Samples Statistics Mean N Std. Deviation Std. Error Mean Pair 1 Duration (minutes) of stops 13.58 65 17.843 2.213 made during the day Duration (minutes) of stops 9.60 8.891 1.103 made at night Page 4 Paired Samples Correlations N Correlation Sig. Pair 1 Duration (minutes) of stops 65 129 306 made during the day & Duration (minutes) of stops made at night Paired Samples Test Paired Differences 95% Confidence Interval of the .. Mean Std. Deviation Std. Error Mean Lower Pair 1 Duration (minutes) of stops 3.985 18.882 2.342 -.694 made during the day - Duration (minutes) of stops made at night Paired Samples Test Paired ... 95% Confidence Interval of the ... Upper df Sig. (2-tailed) Pair 1 Duration (minutes) of stops 8.663 1.701 64 094 made during the day - Duration (minutes) of stops made at night Paired Samples Effect Sizes 95% ... Standardizer Point Estimate Lower Pair 1 Duration (minutes) of stops Cohen's d 18.882 211 .036 made during the day - Duration (minutes) of stops Hedges' correction 18.993 .210 .035 made at night Paired Samples Effect Sizes 95% ... Upper Pair 1 Duration (minutes) of stops Cohen's d 456 made during the day - Duration (minutes) of stops Hedges' correction .453 made at night23. Do pedestrian stops vary in duration depending on the time of day at which they take place? The data set from the Police- Public Contact Survey (PPCS) PPCS Independent Samples for Chapter 11.sav (www.sagepub.com/gau) contains the variables time and minutes , which measure whether a stop took place during the day or at night and the number of minutes the stop lasted. Run an independent-samples / test to determine whether these two variables are related. 1. At an alpha level of .05, will you use the results for the pooled/equal variances / or that for separate/unequal variances? How did you make this decision? 2. What is the obtained value of / ? 3. Would you reject the null at an alpha level of .01? Why or why not? 4. What is your substantive conclusion? In other words, are there significant differences between the two IV groups? Are the IV and the DV related? 24. Do juveniles facing charges for violent crimes have more total charges filed against them compared to juveniles charged with property crimes? The JDCC data set contains information on charge type and total charges. The data file JDCC Independent Samples for Chapter 11.sav (www.sagepub.com/gau) contains the variables offense and charges. Run an independent-samples test to determine whether offense type appears to be related to the total number of charges. 1. At an alpha level of .05, will you use the results for the pooled/equal variances f or that for separate/unequal variances? How did you make this decision? 2. What is the obtained value of ? 3. Would you reject the null at an alpha level of .05? Why or why not? 4. What is your substantive conclusion? In other words, are there significant differences between the two IV groups? Are the IV and the DV related? 25. Critics of the use of DNA evidence in criminal trials sometimes argue that DNA usage would clog up courts due to the delay caused by waiting for labs to return test results. Supporters claim, though, that any such delays would be justified by the improvement in the accuracy of felony convictions and acquittals. The Census of State Court Prosecutors is contained in the file CSCP Independent Samples for Chapter 11.sav. The variable DNA measures whether a prosecutor's office uses DNA evidence in plea negotiations or in criminal trials, and the variable convictions displays the number of felony convictions the office obtained within the past year. Run an independent-samples / test. 1. At an alpha level of .05, will you use the results for the pooled/equal variances / or that for separate/unequal variances? How did you make this decision? 2. What is the obtained value of t ? 3. Would you reject the null at an alpha level of .01? Why or why not? 4. What is your substantive conclusion? In other words, are there significant differences between the two IV groups? Are the IV and DV related? 26. In Question 23, we did not account for PPCS respondents' demographic characteristics. We can ask the same question- whether stop duration varies across day and night-and this time narrow the sample down by gender and race to create a subsample of white males. This strategy removes any potentially confounding effects of gender and race, and allows us to isolate the effects of the dayight variable. Using the data set PPCS Matched Pairs for Chapter 11.sav (www.sagcpub.com/gay), run a dependent samples / test using the day and night variables. 1. What is the obtained value of t? 2. Would you reject the null at an alpha level of .05? Why or why not? 3. What is your substantive conclusion? In other words, are there significant differences between the two IV groups? Are the IV and the DV related