Question

1.In the criminal justice system, a defendant is innocent until proven guilty.Therefore, the nully hypothesis is: " This person is innocent.”

a.In this case, what would be the Type I error?

b.In this case what would be the Type II error?

c.What do you think is the more costly error?

2.Suppose a researcher comes up with a new drug that in fact cures AIDS.She assigns some AIDS patients to receive a placebo, and others to receive the new drug.The null hypothesis is that the drug will have no effect.

a.In this case, what would be the Type I error?

b.In this case, what would be the Type II error?

c.Which do you think would be the more costly error?

3.A manufacturing company is making smoke detectors.They want to conduct a study to determine how well the smoke detectors work.The null hypothesis in this study is that the smoke detectors will not work.

a.In this case, what would be the Type I error?

b.In this case, what would be the Type II error?

c.In this case what would be the more costly error?

4.Much research has found that men tend to perceive more sexuality in women's behavior than women intend (e.g., Abbey, 1982).Haselton and Buss (2000) argue that men seem to be operating from the null hypothesis: that women (especially women they are interested in) are generally behaving in a sexual manner.

a.Is men misperceiving women's sexuality an example of a Type I or Type II error?

b.Which would be the more costly error for men?Why?

5.A researcher review whether scores on a final review are influenced by whether background music is soft, loud, or absent.

a.What is the independent variable?

b.Is the independent variable manipulated or not manipulated?

c.How many levels are there for the independent variable?

d.What is the dependent variable?

e.What is the scale of measurement for the dependent variable?

6.A researcher compares freshmen, sophomores, juniors, and seniors with respect to how much fun they have while attending college (1= no fun at all, 7 = maximum amount of fun).

a.What is the independent variable?

b.Is the independent variable manipulated or not manipulated?

c.How many levels are there for the independent variable?

d.What is the dependent variable?

e.What is the scale of measurement for the dependent variable?

7.A researcher examines whether length of daily exposure to a sun lamp (0 minutes, 30 minutes, or 60 minutes) influences self-reported depression (measured as either "depressed” or "not depressed”).

a.What is the independent variable?

b.Is the independent variable manipulated or not manipulated?

c.How many levels are there for the independent variable?

d.What is the dependent variable?

e.What is the scale of measurement for the dependent variable?

Answer 1

• Q1. a) Type 1 error is that the person is innocent but he was found guilty. Type 1 error is incorrect rejection of the null hypothesis.
• b)Type 2 error is that the person in question is not innocent but failed to recognize that he is guilty. Type 2 error occurs when the null hypothesis and you fail to reject it.
• c)Type 1 error is more costly because its better that many guilty criminals escape than that one innocent suffer.

• Q2. a) Type 1 error would be that the drug will no effect but you believe it would have an affect.
• b) Type 2 error would be that the drug does work but you you reject it and say it doesnt.
• c) Type 2 error would be more costly because one might decide to not give the drug since you believe it might not have any effect.

• Q3. a) Smoke detectors will work when they actually dont.
• b) Smoke detectors do not work when they actually do work.
• c)Type 1 error is more costly since the detectors do not work and might prevent the house from being protected from fire.

• Q4.a) Its Type 2 error since men are perceiving it but it actually not present in women.
• b)Missed detections or Type 2 error is more costly since they are perceiving something which the women do not indicate in their behaviour.

• Q5) a) volume of the music is the independent variable
• b) IV is manipulated since the volume goes from soft to loud
• c) It has 3 levels,soft,loud or absent.
• d) DV is the score obtained.
• e) It is ratio scale. It starts from an absolute zero point and values are assigned to variables.

• Q6 a)IV is college level (freshman, sophomore, junior, or senior)
• b) Independent variable is not manipulated
• c) Ther are 4 levels, freshman,sophomore,junior,senior
• d) DV is how much fun they are having
• e) It is ordinal level of measurement. In this there is a discrete classification of data, in which data are neither measured nor ordered but subjects are merely allocated to distinct categories.

• Q7) a) IV is the sun lamp exposure
  (b) Independent variable is manipulated
  (c) There are 3 levels,0 minutes,30 mins, 60 mins
  (d) Dependent variable is the self-reported depression of the subjects
  (e) It is nominal level of measurement. This indicates categorical data and numbers that are used as identifiers.