Quiz

Question 1

There are 10 red marbles and 40 blue marbles in a jar. What is the probability that the first marble selected from the jar is a red marble?

Answer 1

10/50
.20
20%

Question 2

Sampling error is the difference between the __________ and the ____________.

Answer 2

Sample mean; population mean

Question 3

Birthweights are measured for a sample of 20 infants. The 95% confidence interval for this distribution is 6.2 to 7.4 pounds. Based on this confidence interval which of the following statements is correct?

Answer 3

We are 95% confident that the population mean for birth weight is between 6.2 and 7.4 pounds.

Question 4

Power analysis can be used to determine all of the following except:

Answer 4

If a statistically significant outcome is clinically significant.

Question 5

All of the following describe an effect size index except:

Answer 5

A ratio of variance and sample size.

Question 6

Power analysis can be used to determine

Answer 6

How many subjects are needed to carry out a study.

If an effect size is sufficiently large that a statistically a significant result is probable.

The probability of committing a Type II error

Question 7

Describing and effect sizer index involves

Answer 7

A standardized ratio that estimates the degree to which the null hypothesis is false.

A unitless ratio that allows comparison of results across studies.

A ratio of the difference between groups and the variance within the groups

Question 8

True/False: By changing a level of significance from a = .05 to a = .01, a researcher is making it more difficult to commit a Type I error.

Answer 8

True

Question 9

All of the following assumptions are important for the use of parametric statistics except:

Answer 9

Random assignment to groups

Question 10

These assumptions are important for the use of parametric statistics

Answer 10

Interval or ratio data
Variances are homogeneous
Normal distribution of data