For the following examples, identify which studies involved independent samples or two related samples. Estimates of weekly t.v. viewing time of third-grade girls compared with those of third grade boys. Number of cigarettes smoked by participants before and after an anti-smoking workshop. Problem-solving skills of recognized scientists compared with those of recognized artists who have been matched for IQ.

A colleague of yours is faced with testing a relationship at the .05 level or significance or the .01 level of significance. What is your advice to your colleague?  Why?

A researcher has found a strong relationship between level of education and income and concludes that “higher levels of education cause higher income.” What error has been made?

Do you think the results of the study might be applicable to the whole population? Why or why not?

The study sorted PIR data into three categories:   Use the graphs to estimate the following information from the study. You may wish to record your responses for use in later questions. Part A: The total number of obese men is about  million. Part B: The total number of obese women is about  million. Part C: The number of obese men with PIR<130%  is about  million. Part D: The number of obese women with PIR<130% is about  million.

A recent study on driving behavior examined whether the combination of high driving skills and low safety skills is dangerous. Participants were classified as high or low in driving skill based on responses to a driver-skill inventory, then classified as high or low in safety skill based on responses to a driver-aggression scale. An overall measure of driving risk was obtained by combining several variables such as number of accidents, tickets, tendency to speed, etc. The following data were obtained. Use a 2 x 2 ANOVA with the .05 significance level to evaluate the results. What cutoff score(s) should be used? Driving Skill Low High Safety Skill Low M1=5 M2=4.5 S1=2.7 S2=3.8 N1=6 N2=6 HIgh M3=3 M4=3.5 S3=2.9 S4=2.5 N3=6 N4=6 Group of answer choices +4.35 +3.40 +3.49 +4.26

What is the relative frequency? Give your answer to two decimal places.

Explain the differences between independent samples and dependent samples as it applies to statistical testing of data.

A community college professor is interested in determining the relationship between the number of posts students make on Schoology and their respective grades. He planned to correlate the results from a sample from all his classes, however, due to time constraints, he decided to sample only from students with high grades. As his statistical consultant, state whether or not you support his plans and why.

Suppose you computed r=-0.524 with 20 data points. Is r significant? Explain. 0.05 significance level. Your Answer: