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- An auditor for a local court system is tasked with comparing the rulings of two judges. The auditor needs to determine if Judge Hughes issues shorter sentences than Judge Wilson. The data below are the sentence lengths, in months, issued by each judge in their last twelve cases that dealt with operating a motor vehicle without a license. Test the claim that Judge Hughes issues shorter sentences than Judge Wilson for this particular type of case at the 0.05 level of significance. Let Judge Hughes' sentences be Population 1 and let Judge Wilson's sentences be Population 2. Assume that both populations are approximately normal and that the population variances are equal. Judge 24 12 12 30 Hughes 36 30 12 18 24 12 24 30 Judge 36 36 24 24 24 24 18 12 30 24 18 30 Wilson Copy Data Step 2 of 3: Compute the value of the test statistic. Round your answer to three decimal places.A graduate student is interested in how viewing different types of scenes affects working memory. For his study, he selects a random sample of 36 adults. The subjects complete a series of working memory tests before and after walking in an urban setting. Before the walk, the mean score on the test of working memory was 9.1. After the walk, the mean score was 1.4 higher. The graduate student has no presupposed assumptions about how viewing different types of scenes affects working memory, so he formulates the null and alternative hypotheses as: H00 : μDD = 0 H11 : μDD ≠ 0 Assume that the data satisfy all of the required assumptions for a repeated-measures t test. The graduate student calculates the following statistics for his hypothesis test: Mean difference (MDD) 1.4 Estimated population standard deviation of the differences (s) 1.6 Estimated standard error of the mean differences (sMDMD) 0.2667 Degrees of freedom (df) 35 The t statistic 5.25 The critical values of t…An auditor for a local court system is tasked with comparing the rulings of two judges. The auditor needs to determine if Judge Hughes issues shorter sentences than Judge Wilson. The data below are the sentence lengths, in months, issued by each judge in their last twelve cases that dealt with operating a motor vehicle without a license. Test the claim that Judge Hughes issues shorter sentences than Judge Wilson for this particular type of case at the 0.10 level of significance. Let Judge Hughes' sentences be Population 1 and let Judge Wilson's sentences be Population 2. Assume that both populations are approximately normal and that the population variances are equal. Judge Hughes 24 30 + Judge 18 18 36 30 Wilson 12 36 36 Copy Data Step 1 of 3: State the null and alternative hypotheses for the test. Fill in the blank below. Ho :μ₁ = 1₂ Ha: ₁ 12 24 M₂ 12 30 36 18 36 36 24 12
- A psychology graduate student wants to test the claim that there is a significant difference between the IQs of spouses. To test this claim, she measures the IQs of 9 married couples using a standard IQ test. The results of the IQ tests are listed in the following table. Using a 0.10 level of significance, test the claim that there is a significant difference between the IQs assuming that the population distribution of the paired differences is approximately normal. Let the spouse 1 group be Population 1 and let the spouse 2 group be Population 2. Spouse 1 Spouse 2 IQs of Married Couples 124 113 97 123 121 101 128 116 96 126 119 100 Copy Data Step 2 of 3: Compute the value of the test statistic. Round your answer to three decimal places. 124 111 127 113 107 111Three brands of bacon such as Poorfoods, Sweeps and COD are tested for a fat content with the following sample results: (step by step solution, without using excel) BRAND FAT CONTENT (%) TOTAL Poorfoods 40 43 40 40 43 206 Sweeps 41 42 35 38 34 190 COD 40 35 36 33 36 180 Perform the appropriate test procedure determining whether or not there are differences in the mean fat content of the three bacon brands at 5% level of significance. Ho: Ha: Decision Rule: Computation: ANOVA TABLE: Sources ofVariation Degrees of Freedom Sum of Squares Mean of Sum of Squares F-computed Decision: Conclusion:A study was conducted using 50 mobile network users who volunteered to participate in a research as the entry of the third telco player in the country is on its way. One of the variables studied was the data connection speed in the previous month. Based on the data in the following table, is there a significant difference between the connectivity speeds of the two present mobile networks during the previous month? Use a 5% level of significance and assume that the population variances are equal. 1. The alternative hypothesis for the test would be? 2. The alternative hypothesis for the test would be? 3. What is the computed value of the test statistic? 4. What would be your decision?
- In a random sample of males, it was found that 29 write with their left hands and 212 do not. In a random sample of females, it was found that 70 write with their left hands and 444 do not. Use a 0.01 significance level to test the claim that the rate of left-handedness among males is less than that among females. Complete parts (a) through (c) below.A researcher intends to estimate the effect of a drug on the scores of human subjects performing a task of psychomotor coordination. The members of a random sample of 9 subjects were given the drug prior to testing. The mean score in this group was 9.07, and the sample variance was 17.68. An independent random sample of 10 subjects was used as a control group and given a placebo prior to testing. The mean score in this control group was 15.21, and the sample variance was 27.48. Assuming that the population distributions are normal with equal variances, find a 90% confidence interval for the difference between the population mean scores The confidence interval is<, -,O (Round to two decimal places as needed.)A Gallup poll to survey the top concerns of Americans was conducted. Suppose that 566 women and 465 men were independently and randomly selected and that 322 women and 172 men chose the state of the economy as their biggest concern. Can we conclude that the proportion of women ( p1 ), choosing the state of the economy as their biggest concern, exceeds the proportion of men ( p2 )? Use a significance level of α=0.1 for the test. Step 1 of 6 : State the null and alternative hypotheses for the test. Step 2 of 6 : Find the values of the two sample proportions, pˆ1p^1 and pˆ2p^2. Round your answers to three decimal places. Step 3 of 6 : Compute the weighted estimate of p, p‾p‾. Round your answer to three decimal places. Step 4 of 6 : Compute the value of the test statistic. Round your answer to two decimal places. Step 5 of 6 : Determine the decision rule for rejecting the null hypothesis H0H0. Round the numerical portion of…
- A science project involves testing the effects of different types of music on plant growth. A sample of 24 newly sprouted bean plants is obtained. The plants are randomly assigned to each experimental condition (6 per group). The experimental conditions are: rock music, heavy metal, country, and classical. The dependent variable is the height of each plant after 2 weeks. The ANOVA results are summarized as follows: MSB = 10 and SSW =40. Construct a summary table for this studyUse Excel’s Data Analysis tool to conduct a multiple regression, using Risk of Stroke as the dependent variable, and all the rest of variables as independent variables. Choose confidence level at 99%. Risk of Stroke (%) Age Pressure Smoker (Yes=1) 12 57 152 0 24 67 163 0 13 58 155 0 56 86 177 1 28 59 196 0 51 76 189 0 18 56 155 1 31 78 120 0 37 80 135 1 15 78 98 0 22 71 152 0 36 70 173 1 15 67 135 1 48 77 209 0 15 60 199 0 36 82 119 1 8 66 166 0 34 80 125 1 3 62 117 0 37 59 207 1 Interpret the multiple coefficient of determination R-square. Compare the R-square of the simple linear regression and the R-square of the multiple regression, what does the differences in R-squares tell us? What does F-test for significance tell us?The design of controls and instruments affects how easily people can use them. A student project investigated this effect by asking 25 right handed students to turn a knob with their right hands that moved an indicator by screw action. There were two identical instruments, one with a right-hand thread and the other with a left-hand thread. The table given has the data from the student project.1. Calculate and interpret a 90% confidence interval for the mean time advantage of right hand over left hand threads in the setting above.