Final Pretest + Extra Trivia lol

Question 1

What is the mean and standard deviation of the sampling distribution of p̂ for samples of size ​n​ = 100 if ​p​ = 0.80?

A. 0.70 and 0.0458
B. 0.70 and 0.04
C. 0.80 and 0.0458
D. 0.80 and 0.04
E. Not enough information given to find the mean and sandard deviation of the sampling distribution of p̂

Answer 1

D. 0.80 and 0.04

Question 2

Ross, a paleontologist, found a correlation of 0.64 between X = the geographical area in square miles where fossils of the species are found and Y = the number of years that fossils are extinct species are found in the fossil record. What does r=0.64 tell us?

A. That larger geographical areas caused longer survival of a species.
B. About 64% of the variation in number of years a species appears can be explained by geographical area.
C. That species with large areas for their fossils tend to have longer periods of appearance in the fossil record.
D. About 64% of the variation in the geographical area where fossils are found can be explained by the regression on number of years a species appears.

Answer 2

That species with large areas for their fossils tend to have longer periods of appearance in the fossil record.

Question 3

The distribution of the age at which ​all​ married male BYU students got married is right skewed with μ = 22.9 years and σ = 1.5 years. What is the probability that an SRS of 75 married male BYU students would have a sample mean between 22.8 and 23.0?

A. .281
B. .438
C. .056
D. .562
E. .680
F. Can’t compute using the standard Normal table because the distribution is right skewed, not Normal.

Answer 3

B. .438

Question 4

A sample of 18 pigs was fed a new diet for 8 weeks. Their mean weight gain during this period was x̅ = .78 lb/day with s = .22 lb/day. When can we use the formula x¯±t∗sn√to estimate the mean weight gain of all pigs under this new diet?

A. If the sample of pigs is large.
B. If σ is known.
C. If the sample of pigs is SRS and if weight gains in the sample are not outliers.
D. If the sample pigs is SRS (no other assumptions are required due to the Central Limit Theorem).

Answer 4

C. If the sample of pigs is SRS and if weight gains in the sample are not outliers.

Question 5

In a simple random sample of American adults, 10.6% of 1067 men were left-handed and 7.9% of 1170 women were left-handed. If the test statistic for investigating whether a greater percentage of men are left-handed than women in the whole population is z = 2.22, what is the p-value?

A. 0.9869
B. 0.0132
C. 0.0222
D. 0.0264

Answer 5

B. 0.0132

Question 6

The mean of the sampling distribution of the sample proportion equals p̂

True
False

Answer 6

False (it equals p-null not p-hat)

Question 7

Correlation ignores the distinction between explanatory and response variables.

True
False

Answer 7

True

Question 8

r squared t-test slope of regression line wording

Answer 8

% of the VARIABILITY in (dependent variable) can be explained by (explanatory variable)

Question 9

What is x*?

Answer 9

a value of interest for x

Question 10

t-test slope of regression conclusion wording

Answer 10

Conclude that there is a linear relationship or that there is no LINEAR relationship

Question 11

Relationship between SEb and sample size?

Answer 11

as n increases SEb decreases

Question 12

Relationship between SEb and standard deviation?

Answer 12

as SD increases, SEb increases