Statistics Problems

1. What type of statistical comparison can be made when observed statistics are proportions and the sample size is greater than 30?
a. t-test
b. z-test
c. ANOVA
d. f-test

2. With a normal distribution, we know that
a. Approximately 95% of all observations will fall within one standard deviation of the mean.
b. Approximately 99% of all observations will fall within one standard deviation of the mean.
c. Approximately 95% of all observations will fall within two standard deviations of the mean.
d. Approximately 99% of all observations will fall within two standard deviations of the mean.

3. A parameter represents
a. the geographical boundary of a population.
b. certain characteristics of a random sample.
c. fixed characteristics of a population.
d. fixed characteristics of a nonprobability sample.

4. The standardized normal distribution
a. is symmetrical about its mean
b. has a standard deviation of 1
c. has an infinite number of cases (continuous distribution)
d. all of the above

5. A confidence interval estimates is
a. only as good as its weakest link
b. not really a statistical calculation
c. a specified range of numbers within which a population mean
is expected to lie
d. the same thing as the mode

6. Which type of scale assumes an arbitrary zero point?
a. ratio
b. median
c. interval
d. nominal
e. ordinal

7. Code words, letters, or numbers used by security and intelligence organizations to form secret codes are examples of what type of scales?

a. nominal
b. ordinal
c. interval
d. ratio
e. continuous
8. The question, "How would you judge the price and quality of this product?" is
a. double-barreled
b. leading
c. contain s an implied alternative
d. contains an implied assumption
e. forces generalization on the part of the respondent.

9. Which of the following about interval scales is FALSE?
a. An interval scale exhibits the property of order.
b. Absolute magnitudes cannot be compared using an interval scale because the zero point is established arbitrarily.
c. The number of years the respondent has lived at a particular address is an example of an interval scale.
d. a and b.
e. a, b, and c.

Find the total proportion of the area under the normal curve for the following statements. Include four decimal places. Show your work.

10. below a z score of -1.45 ________

11. above a z score of +1.73 ________

12. between the mean and a z score of +2.11 ________

13. The probability density of the standardized normal distribution is
a. 1.0
b. 0
c. 3.0
d. 2.3
14. Indicate the type of scale is used to answer the following question. What is your job title:
_____ assistant professor; _____ associate professor; _____ full professor.
1. nominal
2. ordinal
3. interval
4. ratio