1. Name the Variable Category: N = Nominal O = Ordinal I = Interval

Stats worksheet 1

Name______

1. Name the variable category: N = nominal O = ordinal I = interval

_____Marital status

_____Age

_____Attitude Measure using Likert type items

_____Number of dropouts

_____Ethnicity

_____2. Which of the following is NOT a characteristic of a good research topic for this class?

a. The topic has theoretical or practical significance.

b. The topic can be investigated through the collection and analysis of data.

c. The topic can be investigated within a year.

d. The topic of research is ethical.

_____3. Juan is an instructional design student. He needs a thesis topic. He is interested in the use of discussion boards for distance education. He approaches his advisor and the advisor sends him away to think some more. Of the following, what is the most likely reason?

a. The topic is not ethical

b. The topic is too narrow c. The topic is too broad

d. The topic is not significant

_____4. The first step in identifying a topic is to:

a. Go to the library and hand-search the journals

b. Read as many empirical studies as you can

c. Select something of interest to you

d. Ask your advisor or colleagues for ideas

____5. If you operationalize a variable, you are doing what to the variable?

a. Manipulating it

b. Controlling it

c. Defining it

d. Mediating it ______6. The measure of central tendency appropriate for nominal data is (choose all that apply)

a. Mode

b. Standard deviation

c. Mean

d. Median

______7. The measure of central tendency appropriate for ordinal data is (choose all that apply)

a. Mode

c. Mean

d. Median

______8. The measure of central tendency appropriate for interval data is (choose all that apply)

a. Mode

c. Mean

d. Median

_____9. Which of the following is a measure of variability

a. Mode

c. Mean

d. Median

_____10. What is the mode of the following distribution:

1 2 4 4 5 5 5 6 6 8 9 11. Using EXCEL, find the mean, mode, median, range, standard deviation of the following sets of data:

Set A: 6, 7, 5, 12, 11, 9, 9, 7, 6, 10, 6

Mean______Range______

Mode______S.D.______

Median______

Set B: 72, 89, 91, 90, 100, 68, 80, 76, 78, 94, 94, 90, 84, 86, 88, 87, 92, 96, 74, 93

Mean______Range______

Mode______S.D.______

Median______

Which of the two sets has less variability? Support your response. (Briefly) 12. Do you think a sample with a mean of 15 and median of 22 is normally distributed? Why or why not?

13. Why is a z score NOT a descriptive statistic?

_____14. To convert a raw score to a z score, one needs the following information

a. raw score and mean

b. raw score and standard deviation

c. mean and standard deviation

d. raw score, mean and standard deviation

15. Malinda received a raw score of 47. Given the test had a mean of 52, a median of 52, and a standard deviation of 3, what is Malinda’s z score? What is her percentile rank?

On that same test, Jeff received a raw score of 59. What is his z score and percentile rank? How does his percentile score compare with Malinda’s? _____16. Suzanne reported a correlation between reading ability and math grades of r = .90 in the first grade. This correlation indicates that in Suzanne’s study

a. reading ability is strongly related to math grades

b. reading and math grades are independent

c. reading ability and math grades are mutually exclusive

d. reading ability and math grades are moderately related

_____17. A strong negative correlation coefficient indicates that

a. two variables are not related

b. two variables are inversely related

c. there has been measurement error

d. there has been calculation error

18. Make a scatterplot with a line of best fit and find the correlation coefficient for the following set of data that compares the score and flight time for seven divers completing a reverse half- somersault.

a. Are the two variables related?

b. How confident are you that the findings are not due to chance?

Score 7.5 8.3 7.6 6.8 7.4 7.5 6.5

Time (s) .45 .45 .45 .40 .41 .40 .46 19. Here’s one more correlation set. Are students’ SAT Verbal Scores related to their SAT Math Scores? Make a scatterplot, line of best fit and the correlation coefficient. Also interpret your findings and tell me how sure you are that the findings are not a result of chance.

SAT SAT

Verbal Math

633 334

665 375

525 300

479 350

660 346

629 345

579 378

591 398

718 368

633 309

435 589

388 678

379 601

315 545

303 667

349 556

421 629

388 677

299 589

348 700