Chapter 11

When it comes to significance testing in social science, which level of risk is most commonly used?

.05

What is considered to be a small effect for Cohen's d?

.17

If the number of participants in Group 1 = 54 and the number in Group 2 = 58, what is the associated degrees of freedom?

110

If the number of participants in Group 1 = 32 and the number in Group 2 = 30, what is the associated degrees of freedom?

60

What does the number 42 represent in the following: t(42) = 5.15, p < .01?

Degrees of freedom

A measure of how different two groups are from one another in their magnitude is the

Effect size

In the effect size formula, what does ES stand for?

Effect size

Effect size is a value that approximates the sample size and is a component of many statistical tests.

False

The sign of the observed t value (i.e., whether it is positive or negative) is a crucial element in conducting the t-test for independent samples.

False

The t-test for independent samples should be used when participants are tested multiple times.

False

researcher wants to create an intervention to improve the well-being of first-semester graduate students, so she gives the professional school counseling students specific doses of rocky road ice cream and the mental health counseling students specific doses of licorice. To analyze the differences in well-being, she would use a(n)

Independent sample t test

. If there is significant difference between the distributions of scores in two groups with effect size at .37, how big are the differences between the two groups?

Medium

Independent means that the groups are

Not related in any way

In the formula that computes a t value, what does n1 represent?

Number of participants for group one

In the effect size formula, what does s stand for?

Standard deviation

What does the symbol t represent in the following: t(42) = 5.15, p < .01?

Test statistics

In the effect size formula, what does X1 bar stand for?

The mean for group one

A t-test may be conducted to detect differences between two groups in which participants are only tested once.

True

Effect size is the magnitude of the differences between groups.

True

Pooled standard deviation is part of the formula for the Cohen's d effect size. Pooled standard deviation is similar to an average of the standard deviations from both groups.

True

The homogeneity-of-variance assumption is an assumption underlying the t-test that states that the amount of variability in both groups is equal.

True

There is an important difference between a significant result and a meaningful result.

True

If you want to examine the difference among the average scores of three unrelated groups, which of the following statistical techniques should you select?

analysis of variance

In order to determine whether or not you will reject the null hypothesis, the test statistic must be compared against the

critical value

What does the number .05 represent in the following: t(58) = 2.001, p < .05?

significance level

What does the number 0.01 represent in the following: t(42) =

significance level

What does the letter t represent in the following: t(58) = 2.001, p < .05?

test statistic

The t-test for independent means is used when you are looking at the difference in average scores of one or more variables within/between _______ group(s) that are _______ of one another.

two, independent

When examining group difference where no direction of the difference is specified, which of the following is used?

two-tailed test

. In the formula that computes a t value, what does represent?

variance for Group 1

1. Which major assumption of the t-test deals with the amount of variability in each group?

variances are equal

If the obtained value is less than the critical value, what should you do?

accept the null hypothesis

In order to compute the test statistic or t value, you must first approximate the sample size by calculating the _____________.

degrees of freedom

What does the number 58 represent in the following: t(58) = 2.001, p < .05?

degrees of freedom

Based on the equation: t(42) = 5.15, p < .01, what is right choice in the following?

group 1= 22; group 2= 22

. What is the assumption that the amount of variability in each of the two groups is equal?

homogeneity of variance

What is the formula used to calculate degrees of freedom for a t-test?

n1 − 1 + n2 − 1

In the t-test for independent samples, the actual statistical test is _

nondirectional

When computing effect size, the sample size is

not taken into account

The t statistic value is also called the

obtained value

The test statistic calculated by the statistical procedure selected is known as the

obtained value

When examining group difference where the direction of the difference is specified, which of the following is used?

one-tailed test

The t-test for independent means is used when each group is tested _

only once

If the obtained value is greater than the critical value, what should you do?

reject the null hypothesis

If your obtained t value is 7.14, and the critical value is 6.10, what decision should you make?

reject the null hypothesis

A researcher wants to study the impact of pizza consumption on the happiness of college freshmen, sophomores, and juniors. What test statistic would the researcher need to use to evaluate the difference in effectiveness between the groups?

analysis of variance

The SPSS output for an independent-samples t-test includes all of the following EXCEPT this:

correlation coefficient

If the effect size is .37, what is your interpretation of the group difference?

Medium

The t-test for independent means is used when there is/are

Only two groups In total

What does the symbol p represent in the following: t(42) = 5.15, p < .01?

Probability

The t-test for independent samples assumes which of the following?

Scores are independent

When it comes to significance testing, the level of risk is

Set by the researcher

What does the number 2.001 represent in the following: t(58) = 2.001, p < .05?

T value

What does the number 5.15 represent in the following: t(42) = 5.15, p < .01?

T value

. If there is no difference between the distributions of scores in two groups, your effect size will be equal to

0

A larger effect size represents a greater difference between the two groups.

True

In the formula that computes a t value, what does represent?

the mean for Group 1

The t-test for independent samples involves how many groups?

two