Author:
Joyce Buda

. What is the risk of performing the using pooled variance, if the variances between the 2 samples are actually unequal (i.e.. fail the F test) ?

A. Your result will only be applicable for a one-tail t-test

B. You will fail to adjust for sample size.

C. You may falsely accept or reject the null hypothesis.

2. The probability that a new advertising campaign will increase sales is assessed as being 0.80. The probability that the cost of developing the new ad campaign can be kept within the original budget allocation is 0.40. Assuming that the two events are independent, the probability that the cost is kept within budget and the campaign will increase sales is: (Select the correct answer from the choices below.)

A. 0.20

B. 0.32

C. 0.40

D. 0.88

3. A confidence interval was used to estimate the proportion of statistics students that are males. A random sample of 115 statistics students generated the following 90% confidence interval: (0.557, 0.673). Based on the interval above, is the population proportion of males equal to 0.60?

A) Yes, and we are 90% sure of it.

B) Yes, and we are 95% sure of it.

C) Maybe. 0.60 is a believable value of the proportion based on the information given.

D) No. The proportion is 54.17%.

E) No, and we are 90% sure of it.

F) No, and we are 95% sure of it.

4. This question is related to simple linear regression. In simple linear regression, the goal is to determine if there is a linear change in the _______ variable based on a change in the ______ variable. The dependent variable will always be a ________ variable. If a negative relationship is found, this means that as the independent variable _______, the dependent variable _______.

(Select the correct answer from the choices below to correctly fill in the blank words.)

A. dependent, independent, categorical, increases, decreases

B. independent, dependent, categorical, increases, decreases

C. independent, dependent, categorical, decreases, increases

D. dependent, independent, numerical, increases, decreases

E. dependent, independent, numerical, decreases, increases

5. According to the empirical rule, if the data form a "bell-shaped curve" (normal distribution), approximately what percent of the observations will be contained within + /- 2 standard deviations from the arithmetic mean. (Select the correct answer from the choices below.)

A. 99.7

B. 95.0

C. 75.0

D. 68.3

6. Which of the following distributions is/are discrete probability distribution(s) (select all that apply)?

A. Normal Distribution

B. Poisson Distribution

C. F Distribution

D. Binomial Distribution

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