use the information below based on raw test scores for two instruments given to the same group of students to answer questions 1-6.
Test II N: 100 N: 100 Low Score: 24 Low Score: 50 High Score: 74 High Score: 149 Mean: 50 Mean: 100 Median: 53 Median: 100 Standard Deviation: 5 Standard Deviation: 10 ===============================================================
1. For which test is it most evident that the distribution was NOT normal (based only on what you can see above)?
a) Test I
b) Test II
c) It is likely that both are normal
d) it is likely that neither is normal
2. If we were to convert the scores in Test I to z-scores, a raw score of 40 would be a z-score of a) -10
3. A z-score of 3 would be the equivalent of a raw score of ______ for Test I.
4. The most extreme outlier in the scores reported above is
a) the 24 in Test I
b) the 74 in Test I
c) the 50 in Test II
d) the 149 in Test II
5. A raw score of 45 on Test I would be equivalent to a raw score of _______ on Test II.
6. On Test I, a score of 51 would be
a) above the 50th percentile
b) below the 50th percentile
c) on the 50th percentile
d) there is inadequate information to answer this question ===============================================================
use the following scenario as the context for answering questions 7 -13. A researcher wished to see if the percent of teachers with masters degrees is related to school effectiveness. He noted that in his state, about 40% of schools were small (less than 300), 50% were moderate sized (300-600), and 10% were large (all were in excess of 800 students. He randomly selected 20 small schools, 25 moderate sized schools, and 5 large schools. He then took the average standardized reading score for juniors for each school and calculated the correlation. He found that the correlation between the percent of teachers with masters and the average reading score was .32. He also looked at school size and found that the correlation between school size and percent teachers with masters was .20. ===============================================================
7. For which of the following variables would it be likely that the median is a better indicator of central tendency than the mean?
a) reading scores
b) school size
c) percent with masters
d) none of the above.
8. School size, if indicated by small, medium, and large, is an example of ________ level data.
9. Suppose the researcher had considered average salary of teachers as well and found that as the average salary increased, the percent of teachers with masters also increased. This would be represented by a ____________ correlation coefficient.
c) insufficient information to answer this question.
10. This is an example of __________ research.
c) it is not a research study.
11. From the information above, about _______ percent of the variance in percent with masters degrees is related to the variance in school size.
12. On the basis of the research presented here, it would make sense to
a) insist that more teachers get masters degrees
b) recognize that better qualified teachers prefer to teach in schools with more highly qualified students
c) recommend that schools that wanted to increase their size should hire more teachers with masters degrees
d) none of the above.
13. If one were trying to generalize to the overall population of schools in a state, the sampling done in this research would be best described as ________ sampling.
a) simple random
d) none of the above
16. If a test has a mean of 500 and a standard deviation of 100 and N = 1000, about how many individuals score below 600 (assuming a normal distribution)? a) 680 b) 840 c) 960 d) 980
17. If a test has a mean of 500 and a standard deviation of 100 and N = 1000, about how many individuals score between 300 and 600 (assuming a normal distribution)? a) 680 b) 820 c) 840 d) 960
18. Salaries for the 100 line workers and clerical staff at a factory range between $20,000 and $40,000 per year, while the salaries for the 8 administrative staff range from $140,000 to $980,000 per year. A researcher wishes to represent the salary of people working at the factory. Which of the following would be most appropriate? a) mean b) median c) mode d) standard deviation
19. A researcher wishes to represent the degree to which salaries vary. Which of the following would be most appropriate.
a) mean b) correlation coefficient c) standard deviation d) mode