Statistics questions
I have 20 questions I'm working on. Some questions are specific to an article. I'm including the 3 articles. I have been working on these questions, and have answered 18, when I copied the questions it did not copy the answers I chose. Not sure if what I have is right. Question 6 and 12 I have not been able to figure out how to get the answer.
Following is the link to the articles on google drive if articles can't be
https://drive.google.com/folderview?id=0B0MDT1WVLFkFNmgxeTVTR2cydHM&usp=sharing

1. Refer to Dale article. What was the rate of committing a type I error for the After School time period?
2. Refer to Montgomery article. Is how heavy a child is (as measured by BMI SD score) significantly related to his or her level of physical activity (PAL) in this study?

3. Researchers risk making a type II error when:

They conclude that means are different 

They conclude that means are the same 

They have too many subjects in their study 

They measure too many variables in their study 
4. Refer to Montgomery article. From the correlation analyses in Figure 1, how much variability does time spent sedentary account for in PAL?

33% 

11% 

57% 

22% 
5. Refer to Montgomery article. In the multiple regression analyses, is sex significantly related to PAL?

Yes 

No 
6. Refer to Montgomery article. If percent MVPA accounts for 4.8% of the variability in PAL, how much variation does age, sex, and BMI SD score (together) account for in PAL?

11.4% 

12.0% 

14.8% 

6.6% 
7. Consider two separate groups of people who had their body fatness measured. The mean and standard deviation for groups 1 and 2 were 37.4% ± 4 % and 38.2% ± 7%, respectively. The spread of scores is:

Greater in group 1 

Greater in group 2 

The same in both groups 

Too low 
8. Refer to Montgomery article. Which variable is inversely related to PAL?

Time spent sedentary 

Time spent in moderate activity 

Age 

None are inversely related 
9. If you wanted to determine whether the number of hours spent in class online was related to exam grades for stats students, which statistical test would you use?

Correlation 


Dependent ttest 


Independent ttest 


ANOVA 10. Because of its dependence on two extreme scores, the ______ is not typically a useful measure of variability.
11. Measures of central tendency include all of the following EXCEPT:
12. Refer to Faigenbaum article. For the chest press results, which statement is correct?
13. Consider two separate groups of people who had their body fatness measured. The mean and standard deviation for groups 1 and 2 were 37.4% ± 4 % and 38.2% ± 7%, respectively. For group 1, the 4% means:

14. If you wanted to determine whether male or female stats students scored better on exams, which statistical test would you use?

Correlation 


Dependent ttest 


Independent ttest 


ANOVA 15. Refer to Dale article. The children on the active day had a higher activity level after school than on the restricted day. Was this difference statistically significant?

16. From the choices below, identify the strongest correlation coefficient.

0.93 

0.90 

0.87 

0.05 
17. Refer to the Dale article. What type of statistical test was used in Table 2 to determine whether children on restricted days versus nonrestricted days had a different activity level after school?

Correlation 

Dependent ttest 

Independent ttest 

ANOVA 
18. If you wanted to determine whether the class’s test grades improved from the midterm to the final exam for stats students, which statistical test would you use?

Correlation 

Dependent ttest 

Independent ttest 

ANOVA 
19. Consider two separate groups of people who had their body fatness measured. The mean and standard deviation for groups 1 and 2 were 37.4% ± 4% and 38.2% ± 7%, respectively. If you wanted to determine whether the two groups differed significantly in their % fat, the appropriate statistical test is:

ANOVA 

Independent ttest 

Dependent ttest 

Correlation 
20. Type I errors are made when, based on the results of a study, the researcher:

Correctly concludes that the intervention was effective 

Incorrectly concludes that the intervention was effective 

Correctly concludes that the intervention was not effective 

Incorrectly concludes that the intervention was not effective 