Test statistics | Mathematics homework help

1. Which one of the following statements is true? Select one:

a. The risk of a Type 1 error can be reduced by reducing the alpha level

b. The risk of a Type 2 error can be reduced by reducing the alpha level

c. The risk of both Type 1 and Type 2 errors can be reduced by increasing the alpha level

d. The risk of both Type 1 and Type 2 errors will be increased by increasing the alpha level

2. Researchers have performed a chi-square test of independence to investigate whether there is a gender difference in the prevalence of right- and left-handedness. Which one of the following statements is true?

Select one:

a. The DV is gender

b. The IV is handedness

c. A p-value of 0.04 would mean that they should reject the null hypothesis and conclude that gender and handedness are independent

d. A p-value of 0.04 would mean that they should reject the null hypothesis and conclude that gender and handedness are not independent

3. Researchers are investigating albatross chick mortality on 2 different islands. On Island 1, 29 chicks were killed by cats, 18 chicks were killed by rats and the remaining 12 died of starvation. On Island 2, 12 chicks were killed by cats, 15 chicks were killed by rats and the remaining 48 died of starvation. What kind of statistical test should they use to compare the causes of death on the 2 islands to see if there is a significant difference?

Select one:

a. Pearson’s correlation coefficient

b. Chi-square test of independence

c. Chi-square goodness-of-fit test

d. Two sample t-test (two-tailed)

e. Paired sample t-test (two-tailed)

4. Which one of the following statements is true?

Select one:

a. A paired sample t-test would be two-tailed if we predict the direction of the difference

b. A two sample t-test would be one-tailed if we predict the direction of the difference

c. A t-test for related samples is another name for the two sample t-test

d. A t-test can only be used if our data are nominal

5. Researchers have been investigating whether there is a sex difference in the body mass of foxes. After statistical analysis, they conclude that males are significantly heavier than females and report that p = 0.03. What is the probability that they have made a Type 1 error?

Select one:

a. 0.97

b. 0.05

c. 0.03

d. 0.5

6. If we want to test our data against a theoretical distribution we should use

Select one:

a. A chi-square test of independence

b. A chi-square goodness-of-fit test

c. A two sample goodness-of-fit t-test

d. A paired sample goodness-of-fit t-test

7. Researchers are investigating whether there is a significant relationship between lecturers’ alcohol consumption and week of the trimester. Which of the following would be most appropriate for the analysis?

Select one:

a. A two-sample t-test

b. A chi-square goodness-of-fit test

c. A paired sample t-test

d. A Pearson correlation coefficient

8. Which one of the following statements is true?

Select one:

a. Chi-square tests assume we have interval or ratio data

b. Pearson’s correlation coefficient assumes we have ordinal data

c. The gradient of a regression line is the value of x when y=0

d. A horizontal regression line means there is no relationship between our IV and DV

9. Researchers conducted a two sample t-test and reported that t=0.05, df = 15 and p=0.90. Which one of the following statements is true?

Select one:

a. They have found a statistically significant difference and should reject the null hypothesis

b. They have found a statistically significant difference and should reject the alternative hypothesis

c. They have found no statistically significant difference and should reject the alternative hypothesis

d. They have found no statistically significant difference and should reject the null hypothesis

10. Researchers have collected data on the oxygen consumption of birds at various environmental temperatures. Statistical analysis of the data produces the regression equation y = 3.47 + 0.12x. What level of oxygen consumption should they expect to find at 10 degrees?

Select one:

a. 4.67

b. 54.42

c. 54.24

d. 4.57