Question 1

3 / 3 pts

Stratified random sampling is used to ensure:rect!

representation of groups indicative of the population

ethicality

randomization

similar groups

Question 2

3 / 3 pts

In recent years, many statisticians have argued

for looser application of measurement requirements

for stricter adherence to the four levels of measurement

that there is only one level of measurement

that Likert scales should be avoided

Question 3

0 / 3 pts

What is the simpler distinction between measurement levels that is common among contemporary statisticians?

correct Answer

categorical and quantitative

You Answered

nominal, ordinal, interval, and ratio

quantitative and qualitative

individual, group, race, and type

Question 4

3 / 3 pts

What does it mean if a sample is “representative”?

Correct!

it has similar characteristics as the population

it is unique

it is ethical

it is a convenience sample

Question 5

3 / 3 pts

The degree to which a study supports a causal relationship is:

Correct!

internal validity

construct validity

discriminant validity

external validity

Question 6

3 / 3 pts

What is a biased sample?

Correct!

a sample that is systematically different from the population

a sample of people with strong opinions

a sample that has uneven groups

a sample that produces results that meet the expectations of researchers

Question 7

0 / 3 pts

Which of these is NOT a typical part of an experiment?

Correct Answer

manipulation of mediators

random assignment of participants to groups

two or more treatments, dosage levels, or interventions

You Answered

assessment of the outcome variable

Question 8

3 / 3 pts

The main purpose of using random assignment in a research study is to:

Correct!

increase the ability to make cause-effect inferences between variable

increase the external validity of a study

increase the ability to generalize the results of a study to a larger population

make the sample resemble the population as closely as possible

Question 9

3 / 3 pts

What percentage of scores are within three standard deviations from the mean?

Correct!

99.72

95.44

68.26

34.13

Question 10

0 / 3 pts

Approximately two-thirds of all values in the standard normal distribution fall within how many standard deviations of the mean?

Correct Answer

1

6

You Answered

3

2.5