1. Identify the independent and dependent variables in the following examples. (2 pts)

1. Research investigating the effects of education on salary.

 

2. Study investigating whether IQ is influenced by number of siblings.

 

3. Researching how gender influences aggression.

 

4. Study examining whether hair color is influenced by the state you were born in.

 

5. Research investigating whether job satisfaction depends on amount of vacation time.

 

6. Studying the effect of teacher expectations on students grades.

 

7. Researching whether or not a person’s major in college depends on their personality.

 

8. Study investigating how diet (vegetarian or omnivore) impacts energy levels.

1. Indicate whether each variable is nominal, ordinal, interval or ratio (2 pts)

1. eye color
2. Social Security numbers
3. speed (in miles per hour)
4. order of finish in a car race
5. SAT scores
6. dollars as a measure of income
7. ranking in science fair (1^st place, 2^nd place, etc.)
8. temperature (in Fahrenheit degrees)

1. What is the essential characteristic of random sampling? (1pt)

 

 

 

2. What is the difference between descriptive and inferential statistics? (1pt)

 

 

 

3. Use the following data to perform the following calculations (3 pts)

(remember to keep all digits until rounding your final answer to 2 decimal places)

1. Σ X

 

 

2. (Σ X)²

 

 

3. Σ X²

5. Complete the following frequency distribution: (3 pts)

Hours of study	f	rf	%	cf	crf	c%
8	15
7	22
6	27
5	16
4	20