Deck 6: Parametric Inferential Statistics

Question 1

For the questions that follow, identify which procedure you would use for each of the given scenarios.
a.Single sample t-test
b.Independent samples t-test
c.Paired samples t-test
A neighborhood of over 300 homes is concerned that residents are overloading their garbage cans.Each sanitation department garbage can allows for the disposal of up to 30 pounds of garbage.A random sample of 20 cans averaged 33.32 lbs.with a standard deviation of 2.9 lbs.Is this strong evidence that residents overload their garbage cans?

Answer 1

A

Question 2

Suppose that aspirin actually does NOT help prevent heart attacks.When we conduct an experiment, our null hypothesis is that rates of heart attacks will be the same for our group taking aspirin and our group taking a placebo.Our data result in p = 0.009.What would result?

A)We correctly fail to reject the null hypothesis.
B)We correctly reject the null hypothesis.
C)We reject the null hypothesis, making a Type I error.
D)We reject the null hypothesis, making a Type II error.
E)We fail to reject the null hypothesis, making a Type II error

Answer 2

C

Question 3

For the questions that follow, identify which procedure you would use for each of the given scenarios.
a.Single sample t-test
b.Independent samples t-test
c.Paired samples t-test
Which takes less time to travel to work -- car or train? We randomly select a sample of 55 business people and measure the time it takes for each of them to ride the train to work AND measure the time it takes for them to take a car to work.Then we compare their travel time to work for both types of commute.

Answer 3

C

Question 4

For the questions that follow, identify which procedure you would use for each of the given scenarios.
a.Single sample t-test
b.Independent samples t-test
c.Paired samples t-test
A professor wants to know which of two teaching methods is more effective, the traditional method or the Harkness method.30 students are randomly assigned to the traditional method and 30 students are randomly assigned to the Harkness method.After six weeks of class, the professor gives all the students a quiz to assess their current understanding of the material.Is the average of the Harkness method students higher than that of the traditional method students? Is this difference statistically significant?

Question 5

We are about to test a hypothesis using data from a well-designed study.Which is/are true?
I)A small p-value would be strong evidence against the null hypothesis.
II)We can set a higher standard of proof by choosing alpha = 0.10 instead of 0.05.
III)Type I error is equal to our alpha level.

A)None
B)I only
C)II only
D)III only
E)I and III only

Question 6

A p-value indicates

A)The probability that the null hypothesis is true.
B)The probability that the alternative hypothesis is true.
C)The probability the null is true given the observed statistic.
D)The probability of the observed statistic given that the null hypothesis is true.
E)The probability of the observed statistic given that that alternative hypothesis is true.

Question 7

In the justice system, there is a presumption of innocence.The null hypothesis is that the suspect is innocent.Which of the following is NOT correct based on the given situation?

A)If p < .05, we would reject the null hypothesis that the person is innocent.
B)If p < .05, we would reject the alternative hypothesis that the person is guilty.
C)Type I error is when an innocent person goes to jail.
D)Type II error is when a guilty person does NOT go to jail.
E)If we increase our alpha-level, we are increasing the probability of making a Type I error.