Given this already solved problem, how could you determine whether homogeneity of variance is satisfied for this analysis, and be clear on how you decided this. In Exercise 7.25, we saw data from Everitt that showed that girls receiving cognitive behavior therapy gained weight overthe course of that therapy. However, it is possible that they just gained weight because they got older. One way to controlfor this is to look at the amount of weight gained by the cognitive therapy group (n = 29) in contrast with the amountgained by girls in a Control group (n = 26), who received no therapy. The data on weight gain for the two groups is shownbelow.ControlCognitive Therapy-0.53.31.7-9.1-9.311.30.72.1-5.40.0-0.1-1.412.3-1.0-0.71.4-2.0- 10.6-3.5-0.3-3.7- 10.2- 12.2-4.614.9-6.73.5-0.811.62.817.12.4-7.10.3-7.612.66.2-0.21.81.61.93.711.73.9-9.215.96.10.18.3- 10.21.115.4-4.0-0.720.9Мean-0.453.01St Dev.7.997.31Variance63.8253.41Run the appropriate test to compare the group means. What wouldyouconclude? The t statistic is,(+),where, X= mean of first groupmean of second groupyand combined variance,(ns; + n3s;)S* =Step 2We have,Ho : Hs = Hy: mean of both group are not significantly different> H: 'Hwhere H, = mean of girls receiving no therapy, i.e controlHy = mean of girls receiving cognitive therapyStep 3From given,I = -0. 45 y = 3.01sI = 7.99 2 = 7.31NI = 26n2 = 29Now the combined variance,(26 * 7.99 + 29 * 7.326429-23209439553= 60. 5564Step 4The test statistic,60.5564= -1. 6462As it is a left tailed test, and n, + 12 - 2 = 26 + 29 – 2 = 53 > 30,hence t-Z-The calculated t=-1.6462The tabulated Z for left-tailed at 0.05 level of significance=-1.645Asi.e - 1.646 < -1. 645Theis rejected, and the mean weight of girls getting cognitive therapy is greater than theHomean weight of girls from control group.

Name: Given this already solved problem, how could you determine whether hom
Uploaded: 2024-03-20T07:07:50.000Z
Channel: Bartleby
Description: Given this already solved problem, how could you determine whether homogeneity of variance is satisfied for this analysis, and be clear on how you decided this. In Exercise 7.25, we saw data from Everitt that showed that girls receiving cognitive beh

The hypothesis for the homogenity of variances is H0 : σ12=σ22 againstH1 : σ12≠σ22 Adding the…

Answered: Given this already solved problem, how…

Math

Statistics

Given this already solved problem, how could you determine whether homogeneity of variance is satisfied for this analysis, and be clear on how you decided this

Linear Algebra: A Modern Introduction

4th Edition

ISBN:9781285463247

Author:David Poole

Publisher:David Poole

Chapter7: Distance And Approximation

Section7.3: Least Squares Approximation

Problem 31EQ

See similar textbooks

Similar questions

The director of an obesity clinic in a large northwestern city believes that drinking soft drinks contribute to obesity in children. To determine whether a relationship exists between these two variables, she conducts the following pilot study. Eight- 12-year-old male volunteers are randomly selected from children attending a local junior high school. Parents of the children are asked to monitor the number of soft drinks consumed by their child over a one week period. The children are weighed at the end of the week and their weights converted into body mass index (BMI) values. The BMI is a common index used to measure obesity and takes into account both height and weight. An individual is considered obese if they have a BMI value 30. The following data or collected: child. # of soft drinks consumed BMI 1 3 20 2 1 18 3…
If a newborn lab rat receives a hormone and its weight (in ounces) is converted into a z score that is greater than +2.00, what would the researcher most likely conclude about whether or not the hormone had an effect on the rat's weight?
The researchers reported:" A 2x2 ANOVA revealed, first of all, a main effect for depletion, indicating that depleted individuals generated less ideas (M = 9.40, SD = 5.64) than non-depleted individuals (M = 12.44, SD = 7.34), F (1, 108) = 6.03, p = .016, n2 = .05. This effect was qualified by the expected interaction with [perseverance], F (1,108) = 4.52, p = .036, n2 = .05". What size are the effects for the main effect of depletion and for the interaction between depletion and perseverance, according to Cohen's conventions? a. These are small- to -medium effects b. These are non existent effects c. These are large effects d. We are unable to tell from from the n2 / r2 statistics
An experiment to determine if a migraine medication decreases a person's average number of monthly migraines is performed on 400 people who report they have several migraines a month. Researchers randomly assigned 200 people to the treatment group and 200 people to the control group. After the study, the researchers determined that 48 of the subjects in the treatment group and 28 of the subjects in the control group average fewer migraines per month. The data from the two groups are resampled 150 times, and the table shows the distribution of the differences of the proportions for the reconfigured treatment and control groups.
Researchers investigated the possible beneficial effect on heart health of drinking black tea and whether adding milk to the tea reduces any possible benefit. Twenty-four volunteers were randomly assigned to one of three groups. Every day for a month, participants in group 1 drank two cups of hot black tea without milk, participants in group 2 drank two cups of hot black tea with milk, and participants in group 3 drank two cups of hot water but no tea. At the end of the month, the researchers measured the change in each of the participants’ heart health. Did the researchers conduct an experiment or an observational study? Explain. Why did the researchers include a group who drank hot water but no tea? Is it reasonable to generalize the results of the study beyond the 24 participants? Explain why or why not.
An article indicated that the biggest issue facing e-retailers is the ability to turn browsers into buyers. The article stated that less than 10% of browsers buy something from a particular website. A SRS of 2000 browsers was taken of which 180 made a purchase. Let alpha = .10.
Which of the independent variables retains the strongest association with the number of children a respondent has when all other variables in the model are controlled? What is that association? Which has the weakest when other variables are controlled?
Does posting calorie content for menu items affectpeople’s choices in fast-food restaurants? According to results obtained by Elbel, Gyamfi, and Kersh(2011), the answer is no. The researchers monitoredthe calorie content of food purchases for children andadolescents in four large fast-food chains before andafter mandatory labeling began in New York City. Although most of the adolescents reported noticing thecalorie labels, apparently the labels had no effect ontheir choices. Data similar to the results obtained showan average of M = 786 calories per meal with s =85 for n =100 children and adolescents before thelabeling, compared to an average of M = 772 calorieswith s = 91 for a similar sample of n = 100 after themandatory posting.a. Use a two-tailed test with a = .05 to determinewhether the mean number of calories after theposting is significantly different than before caloriecontent was posted.b. Calculate r2to measure effect size for the mean difference.
Which of the independent variables retains the strongest association with the number of children a respondent has when all other variables in the model are controlled?
A study of 6600 men found that those who consumed a moderate amount of alcohol (one drink or less per night ) have lower mortality(on the average ) than Thoose who drink none is the is this good evidence that drinking a moderate amount causes lower mortality? A) yes because the study is an experiment B) no becuase who drink a moderate amount may differ from nodeinkers in other ways such as income and exercise that affect mortality c) no because we can't generalize from 6600 people to the millions of adults in the country D) yes because the sample is so large that the margin of error will be quite small
A suburban hotel derives its revenue from its hotel and restaurant operations. Theowners are interested in the relationship between the number of rooms occupied on anightly basis and the revenue per day in the restaurant. Below is a sample of 25 days(Monday through Thursday) from last year showing the restaurant income and numberof rooms occupied.
HIV/AIDS patients are regularly monitored for their CD4 counts in order to make sure that antiretroviral therapies are effectiveSuppose the distribution of CD4 counts in a population is approximately normal with mu = 237 and sigma = 43 . HIV patients are defined as moving into the AIDS stage of their disease course after their CD4 counts are less than 200. What proportion of patients in this population is suffering from AIDS?