Under what circumstances will the main effects in a factorial study not provide an accurate description of the results?

An industrial/organizational psychologist has been consulting with a company that runs weekend job-seeking workshops for the unemployed. She collected data on several issues related to these workshops and, after conducting statistical tests, obtained statistically significant findings. She needs to find a way to evaluate effect size so that she can make recommendations to the company. One of the psychologist’s findings is that immediately after the workshop, a sample of 81 job seekers who received training on using the Internet to find job listings worked more than 30 hours per week an average of 8.7 months in the last year, with a standard deviation of 4.1. The typical job seeker works 7.4 months. The psychologist finds that the estimated Cohen’s d is    , the t statistic is 2.83, and r² is    .   Using Cohen’s d and Cohen’s guidelines for interpreting the effect size with the estimated Cohen’s d, there is a    treatment effect. Using r² and the extension of Cohen’s guidelines…

An industrial/organizational psychologist has been consulting with a company that runs weekend job-seeking workshops for the unemployed. She collected data on several issues related to these workshops and, after conducting statistical tests, obtained statistically significant findings. She needs to find a way to evaluate effect size so that she can make recommendations to the company. One of the psychologist's findings is that 18 months after the workshop, a sample of 81 job seekers who received training on setting career goals worked more than 30 hours per week an average of 8. 7 months in the last year, with a standard deviation of 4.1. The typical job seeker works 7.4 months. The psychologist finds that the estimated Cohen's d is _______ (three decimals)

Question 5 Consider a two way-factorial ANOVA with two factors: homework and test anxiety. Homework has two categories (prepared homework vs. did not prepare) and so has test anxiety (test anxiety vs. no text anxiety). Homework and test anxiety are used to predict the continuous outcome variable test score. The statistical model includes significant main effects and a significant interaction effect. Indicate for each of the statements whether it is correct. Correct Incorrect The difference in test scores between pupils with and without test anxiety differs between those who prepared their homework and those who did not. The effect of having prepared homework on test scores differs across pupils who have test anxiety and pupils who do not have test anxiety.

Using the latest in medical technology, an orthopedic doctor has developed a new surgical procedure that he believes is an improvement over the standard procedure. He wants to study whether the mean recovery time of patients who have the new procedure is less than the mean recovery time of patients who have the standard procedure. The doctor studies a random sample of 11 patients who have the new procedure and a random sample of 10 patients who have the standard procedure. (These samples are chosen independently.) The doctor records each patient's recovery time (in days). These data are shown in the table. Recovery times (in days) 350, 284, 291, 393, 295, 377, 401, 371, 423, 449, 364 New procedure Standard procedure 435, 409, 419, 423, 388, 410, 412, 438, 396, 424 Send data to calculator Send data to Excel Assume that the two populations of recovery times are approximately normally distributed. Can the doctor conclude, at the 0.01 level of significance, that the population mean of the…

A sports psychologist studied the effect of a motivational program on number of injuries in one year among players of three different sports (baseball, football, and basketball). Players were randomly assigned to one of two conditions: either participate in a motivational program or none (control). Data was collected on the number of injuries sustained by each athlete that season. Question: If p = .024 for the main effect of sports, what should the researcher conclude?

How to conduct an observational study on to answer the question: “Are males more likely than females to be dog owners? For example, “I went to the park during the hours of 2:00-4:00 pm on a Saturday afternoon. I observed 10 dog owners, two were female, eight were male. It appears that more females than males are dog owners.” Finally, your report should also include your study limitations—that is, what factors could be present that would make my conclusions incorrect?

Explain why blinding is a reasonable strategy in many experiments. O Blinding helps researchers study the control effect better, since knowing if you are in the control group can have a mental effect on results. O Blinding can help solve the doubling issue in research, where people feel they need to match those around them in response/measurement. O Blinding keeps people and researchers from deliberately skewing the effects of the experiment, or to highlight a placebo effect. O Blinding can help solve the singling issue in research, where people feel they need to be unique from those around them in response/measurement.

For a two-factor ANOVA with two levels of factor A, two levels of factor B, and a separate sample of n = 5 participants in each treatment condition, the two means for level A1 are 6 and 8, and the two means for level A2 are 6 and 10. For these data, what is the value of SSB?

W. Thomas Boyce, a professor and pediatrician at the University of British Columbia, Vancouver, has studied interactions between individual differences in physiology and differences in experience in determining health and well-being. Dr. Boyce found that some children are more sensitive to their environments. They do exceptionally well when the environment is supportive but are much more likely to have mental and physical health problems when the environment has challenges. You decide to do a similar study, conducting a factorial experiment to test the effectiveness of one environmental factor and one physiological factor on a physical health outcome. As the environmental factor, you choose two levels of stressful life events. As the physiological factor, you choose three levels of immune reactivity. The outcome is number of respiratory illnesses in the previous 12 months, and the research participants are kindergartners.