cnl 540 3.2

A therapist wants to study the effects of yoga and Which of the following is the best description of the experimental design? meditation on stress relief. She has 60 volunteers who experience varying levels of stress. She believes that the volunteers' professions could have an effect on the results. A preliminary survey reveals that 22 of the volunteers are in high-stress professions. The therapist randomly assigns 11 of these subjects to practice yoga and the remaining 11 to practice meditation. Nineteen of the other 38 volunteers are randomly assigned to practice yoga and the remaining 19 to practice meditation. Before the experiment begins, all the participants will be asked to rate their stress levels on a scale of 0 to 10, with 0 representing "no stress" and 10 representing "highest level of stress." At the end of one month, the subjects will be asked to rate their stress levels again. The differences in stress levels will be compared for the different stress-relieving activities…

Which of the following is the best description of the experimental design? A therapist wants to study the effects of yoga and meditation on stress relief. She has 60 volunteers who experience varying levels of stress. She believes that the volunteers' professions could have an effect on the results. A preliminary survey reveals that 22 of the volunteers are in high-stress professions. The therapist randomly assigns 11 of these subjects to practice yoga and the remaining 11 to practice meditation. Nineteen of the other 38 volunteers are randomly assigned to practice yoga and the remaining 19 to practice meditation. Before the experiment begins, all the O observational study matched pairs design randomized block design completely randomized design participants will be asked to rate their stress levels on a scale of 0 to 10, with 0 representing "no stress" and 10 representing "highest level of stress." At the end of one month, the subjects will be asked to rate their stress levels again.…

A sociologist wants to investigate the question, "Is there a relationship between texting during class and grade-point-average (GPA) among high school seniors in a large district?" Which study design is most appropriate?     Before the semester starts, randomly select 40 seniors from each high school who do not text during class. Assign 20 to the texting treatment group (text three or more times during every class meeting) and 20 to the control group (no texting during class). At the end of the semester, obtain each student’s GPA from the appropriate admissions and records office. Compare the GPA of students who routinely text during class to the GPA of students who do not text during class. Before the semester starts, randomly select 40 seniors from each high school who do not text during class. Assign 20 to the texting treatment group (text three or more times during every class meeting) and 20 to the control group (no texting during class). At the end of the semester,…

When two independent variables produce effects when combined that would not be present if each independent variables was manipulated in a separate study, we say that there is O no main effect. O only a measured variable an interaction. O a planned comparison. rist and Stangor (2001) studied prejudice and found that you can't predict a person's behavior toward minorities on the basis of whether they are high or low

The director of student services at Oxnard College is interested in whether women are just as likely to attend orientation as men before they begin their coursework. A random sample of freshmen at Oxnard College were asked what their gender is and whether they attended orientation. The results of the survey are shown below: Data for Gender vs. Orientation Attendance Women Men Yes 440 410 No 238 239 What can be conduded at the a - 0.10 level of significance? For this study, we should use z-test for a population proportion a. The null and alternative hypotheses would be: Ho: Select an answer v Select an answer v Select an answer v (please enter a decimal and note that p1 and ul represent the proportion and mean women and and u2 represent proportion and mean for men.) H: Select an answer v Select an answer v Select an answer v (Please enter a decimal) b. The test statistic ? v (please show your answer to 3 decimal places.) c. The p-value = (Please show your answer to 4 decimal places.) d.…

After completing the experiment, Kendall wants to see if the difference between the averages for the control and treatment groups was due to the treatment or not. To investigate this, she performs a significance test. The first step is to do a simulation using the data. She randomly reorganizes all of the data into two groups, A and B, each of size 25. In this simulation, group A plays the role of the treatment group and group B plays the role of the control group. Group A: quiz scores 63 79 72 69 68 72 69 73 72 77 84 83 71 74 80 84 63 79 77 78 73 83 72 72 75 Mean: 74.48 Group B: quiz scores 68 88 79 62 84 71 72 61 71 76 79 77 73 87 88 72 81 80 60 84 80 70 89 81 69 Mean: 76.08 Remember that the average for the treatment group was 2.4 higher than the average for the control group in the original experiment. Kendall wants to compare this with the simulation results. So, she subtracts the average for group B from the average for group A. What is this value?

The director of student services at Oxnard College is interested in whether women are less likely to attend orientation than men before they begin their coursework. A random sample of freshmen at Oxnard College were asked what their gender is and whether they attended orientation. The results of the survey are shown below: Data for Gender vs. Orientation Attendance Women Men 431 187 Yes 442 No 214 What can be concluded at the ax = 0.10 level of significance? For this study, we should use Select an answer a. The null and alternative hypotheses would be: Ho: Select an answer Select an answer Select an answer (please enter a decimal and note that p1 and μl represent the proportion and mean for women and p2 and 2 represent the proportion and mean for men.) H₁: Select an answer Select an answer Select an answer (Please enter a decimal) (please show your answer to 3 decimal places.) b. The test statistic c. The p-value = d. The p-value is ? a e. Based on this, we should Select an answer the…

A psychologist conducts a 2 x 3 x 2 ANOVA. How many main effects are possible? How many interactions are possible?

Shopping cart abandonment is a major concern for online retailers. This happens when a visitor to the online retailer puts one or more items in their virtual shopping cart but then abandons the cart, leaving the retailer without having made a purchase. To reduce cart abandonment, one online retailer is considering a “pop-up” free shipping offer to visitors who put an item in their virtual shopping cart. The online retailer decided to test the effectiveness of this free shipping offer. During a randomly selected two-week period, 718 visitors to the website placed at least one item in their virtual shopping cart. The retailer offered free shipping to 350 of those visitors; the remainder did not get the offer. Of those who received the free shipping offer, 191 abandoned their carts. Of those who did not receive the offer, 246 abandoned their carts.Complete the contingency table with actual frequencies (not probabilities), including joint and marginal frequencies, using the information…

Shopping cart abandonment is a major concern for online retailers. This happens when a visitor to the online retailer puts one or more items in their virtual shopping cart but then abandons the cart, leaving the retailer without having made a purchase. To reduce cart abandonment, one online retailer is considering a “pop-up” free shipping offer to visitors who put an item in their virtual shopping cart. The online retailer decided to test the effectiveness of this free shipping offer. During a randomly selected two-week period, 718 visitors to the website placed at least one item in their virtual shopping cart. The retailer offered free shipping to 350 of those visitors; the remainder did not get the offer. Of those who received the free shipping offer, 191 abandoned their carts. Of those who did not receive the offer, 246 abandoned their carts. 1. Complete the contingency table with actual frequencies (not probabilities), including joint and marginal frequencies, using the information…