Question 1

A treatment effect

Accepted Answer

A) is found by comparing the mean score in each condition with the grand mean. 
B) reflects the strength of the relationship between the independent and dependent variables. 
C) is found by calculating the mean score of both groups combined. 
A) is found by comparing the mean score in each condition with the grand mean. 
B) reflects the strength of the relationship between the independent and dependent variables. 
C) is found by calculating the mean score of both groups combined.

Question 2

The standard error of the difference between two independent means is influenced by _____.

Accepted Answer

A) the sample size of both groups 
B) population variance of both groups 
C) both a and b 
D) none of these 
A) the sample size of both groups 
B) population variance of both groups 
C) both a and b 
D) none of these

Question 3

The standard error of the difference becomes smaller as the sample sizes _____ and the variability of the scores in the populations _____.

Accepted Answer

A) decrease;increases 
B) decrease;decreases 
C) increase;decreases 
D) increase;increases 
A) decrease;increases 
B) decrease;decreases 
C) increase;decreases 
D) increase;increases

Question 4

What is an estimated pooled variance?

Accepted Answer

A) the weighted average of the variances estimates 
B) the variance of the difference between the sample means 
C) the sum of the two variances estimates 
D) the variance of the populations from which the samples were drawn 
A) the weighted average of the variances estimates 
B) the variance of the difference between the sample means 
C) the sum of the two variances estimates 
D) the variance of the populations from which the samples were drawn

Question 5

A physical therapist is interested in whether people with different bone structures will be affected differently by her new therapy program.She randomly chooses two groups of patients based on bone type: small-boned frame (XS)and large-boned frame (XL).Patients all had similar injuries.She measures the number of days each person takes to progress to a predetermined point.Here is the data:  
What is the observed value of the independent groups t test?

Accepted Answer

A) -0.61 
B) -1.23 
C) -1.56 
D) -1.77 
A) -0.61 
B) -1.23 
C) -1.56 
D) -1.77

Question 6

If the sample sizes in the two groups are each greater than _____ and roughly comparable,then the independent groups t test is robust to rather severe departures of the _____ assumption.

Accepted Answer

A) 40;normality 
B) 100;heterogeneity of variance 
C) 40;probability 
D) 100;unequal n 
A) 40;normality 
B) 100;heterogeneity of variance 
C) 40;probability 
D) 100;unequal n

Question 7

What is eta-squared?

Accepted Answer

Eta-squared indexes the strength of the

Question 8

The quantity ó2 can best be estimated by combining,or pooling,the variance estimates from the two samples to obtain a pooled variance estimate.

Accepted Answer

A) True 
 B)False

Question 9

Eta-squared indexes the _____ of the relationship between the independent and dependent variables since it represents the _____ of variability in the dependent variable that is associated with the independent variable.

Accepted Answer

A) direction;proportion 
B) strength;proportion 
C) nature;percentage 
D) significance;percentage 
A) direction;proportion 
B) strength;proportion 
C) nature;percentage 
D) significance;percentage

Question 10

The set of all t values more extreme than the critical values constitutes a(n)_____ result or more formally,the _____ region.

Accepted Answer

A) expected;rejection 
B) unexpected;rejection 
C) expected;acceptance 
D) unexpected;acceptance 
A) expected;rejection 
B) unexpected;rejection 
C) expected;acceptance 
D) unexpected;acceptance

Question 11

An independent groups t-test has _____levels of the independent variable.

Accepted Answer

A) 2 levels 
B) 3 levels 
C) 1 level 
D) None of these 
A) 2 levels 
B) 3 levels 
C) 1 level 
D) None of these

Question 12

The alternative hypothesis states that there is a relationship between the independent variable and the dependent variable.

Accepted Answer

A) True 
 B)False

Question 13

The Independent groups t-test assumes all of the following except_____.

Accepted Answer

A) homogeneity of variance 
B) between subjects design 
C) the dependent variable is ordinal 
D) the population is normally distributed 
A) homogeneity of variance 
B) between subjects design 
C) the dependent variable is ordinal 
D) the population is normally distributed

Question 14

The independent samples t test is reasonably robust to violations against which assumptions?

Accepted Answer

A) independent and random selection of both samples from their respective populations 
B) scores in each population are normally distributed 
C) scores in the two populations have equal variances 
D) both a and b 
E) both b and c 
A) independent and random selection of both samples from their respective populations 
B) scores in each population are normally distributed 
C) scores in the two populations have equal variances 
D) both a and b 
E) both b and c

Question 15

A physical therapist is interested in whether people with different bone structures will be affected differently by her new therapy program.She randomly chooses two groups of patients based on bone type: small-boned frame (XS)and large-boned frame (XL).Patients all had similar injuries.She measures the number of days each person takes to progress to a predetermined point.Here is the data:  
What are the degrees of freedom for the t test for two independent samples?

Accepted Answer

A) 3 
B) 25 
C) 26 
D) 27 
A) 3 
B) 25 
C) 26 
D) 27

Question 16

Independent-groups t tests may be used to analyze the relationship between two variables when _____.

Accepted Answer

A) the dependent variable is quantitative 
B) the independent variable is between-subjects in nature 
C) the independent variable has only two levels 
D) all of these 
A) the dependent variable is quantitative 
B) the independent variable is between-subjects in nature 
C) the independent variable has only two levels 
D) all of these

Question 17

1.00 minus eta-squared represents the proportion of variability in the dependent variable that is not associated with the independent variable--that is,the proportion of sample variability that is due to disturbance variables.

Accepted Answer

A) True 
 B)False

Question 18

Many properties of a sampling distribution of the mean do not hold for a sampling distribution of the difference between two independent means.

Accepted Answer

A) True 
 B)False

Question 19

The independent groups t test assumes that the two population variances are unequal,or heterogeneous.

Accepted Answer

A) True 
 B)False

Question 20

The total variability in the dependent variable,as represented by SSTOTAL,can be spilt up,or partitioned,into two components:

Accepted Answer

A) SSEXPLAINED + SSERROR 
B) SSUNEXPLAINED + SSERROR 
C) SSEXPLAINED + SSIV 
D) none of these 
A) SSEXPLAINED + SSERROR 
B) SSUNEXPLAINED + SSERROR 
C) SSEXPLAINED + SSIV 
D) none of these

A treatment effect

The standard error of the difference between two independent means is influenced by _____.

The standard error of the difference becomes smaller as the sample sizes _ and the variability of the scores in the populations _.

What is an estimated pooled variance?

If the sample sizes in the two groups are each greater than _ and roughly comparable,then the independent groups t test is robust to rather severe departures of the _ assumption.

What is eta-squared?

The quantity ó² can best be estimated by combining,or pooling,the variance estimates from the two samples to obtain a pooled variance estimate.

Eta-squared indexes the _ of the relationship between the independent and dependent variables since it represents the _ of variability in the dependent variable that is associated with the independent variable.

The set of all t values more extreme than the critical values constitutes a(n)_ result or more formally,the _ region.

An independent groups t-test has _____levels of the independent variable.

The alternative hypothesis states that there is a relationship between the independent variable and the dependent variable.

The Independent groups t-test assumes all of the following except_____.

The independent samples t test is reasonably robust to violations against which assumptions?

Independent-groups t tests may be used to analyze the relationship between two variables when _____.

1.00 minus eta-squared represents the proportion of variability in the dependent variable that is not associated with the independent variable--that is,the proportion of sample variability that is due to disturbance variables.

Many properties of a sampling distribution of the mean do not hold for a sampling distribution of the difference between two independent means.

The independent groups t test assumes that the two population variances are unequal,or heterogeneous.

The total variability in the dependent variable,as represented by SS_TOTAL,can be spilt up,or partitioned,into two components:

Introduction and Mathematical Preliminaries

Frequency and Probability Distributions

Percentiles percentile Ranks standard Scores and the Normal Distribution

Pearson Correlation and Regression: Descriptive Aspects

Measures of Central Tendency and Variability

Estimation and Sampling Distributions

Hypothesis Testing: Inferences About a Single Mean

Probability

Principles of Research Design and Statistical Preliminaries for Analyzing Bivariate Relationships

Correlated Groups T-Test

One-Way Repeated Measures Analysis of Variance

Pearson Correlation and Regression: Inferential Aspects

Chi-Square Test

Nonparametric Statistics

Two-Way Between-Subjects Analysis of Variance

Overview and Extension: Statistical Tests for More Complex Designs

Filters

Exam 10: Independent Groups T -Test

A treatment effect

The standard error of the difference between two independent means is influenced by _____.

The standard error of the difference becomes smaller as the sample sizes _____ and the variability of the scores in the populations _____.

What is an estimated pooled variance?

If the sample sizes in the two groups are each greater than _____ and roughly comparable,then the independent groups t test is robust to rather severe departures of the _____ assumption.

What is eta-squared?

The quantity ó2 can best be estimated by combining,or pooling,the variance estimates from the two samples to obtain a pooled variance estimate.

Eta-squared indexes the _____ of the relationship between the independent and dependent variables since it represents the _____ of variability in the dependent variable that is associated with the independent variable.

The set of all t values more extreme than the critical values constitutes a(n)_____ result or more formally,the _____ region.

An independent groups t-test has _____levels of the independent variable.

The alternative hypothesis states that there is a relationship between the independent variable and the dependent variable.

The Independent groups t-test assumes all of the following except_____.

The independent samples t test is reasonably robust to violations against which assumptions?

Independent-groups t tests may be used to analyze the relationship between two variables when _____.

1.00 minus eta-squared represents the proportion of variability in the dependent variable that is not associated with the independent variable--that is,the proportion of sample variability that is due to disturbance variables.

Many properties of a sampling distribution of the mean do not hold for a sampling distribution of the difference between two independent means.

The independent groups t test assumes that the two population variances are unequal,or heterogeneous.

The total variability in the dependent variable,as represented by SSTOTAL,can be spilt up,or partitioned,into two components:

Introduction and Mathematical Preliminaries

Frequency and Probability Distributions

Percentiles percentile Ranks standard Scores and the Normal Distribution

Pearson Correlation and Regression: Descriptive Aspects

Measures of Central Tendency and Variability

Estimation and Sampling Distributions

Hypothesis Testing: Inferences About a Single Mean

Probability

Principles of Research Design and Statistical Preliminaries for Analyzing Bivariate Relationships

Correlated Groups T-Test

One-Way Repeated Measures Analysis of Variance

Pearson Correlation and Regression: Inferential Aspects

Chi-Square Test

Nonparametric Statistics

Two-Way Between-Subjects Analysis of Variance

Overview and Extension: Statistical Tests for More Complex Designs

Filters

The standard error of the difference becomes smaller as the sample sizes _ and the variability of the scores in the populations _.

If the sample sizes in the two groups are each greater than _ and roughly comparable,then the independent groups t test is robust to rather severe departures of the _ assumption.

The quantity ó² can best be estimated by combining,or pooling,the variance estimates from the two samples to obtain a pooled variance estimate.

Eta-squared indexes the _ of the relationship between the independent and dependent variables since it represents the _ of variability in the dependent variable that is associated with the independent variable.

The set of all t values more extreme than the critical values constitutes a(n)_ result or more formally,the _ region.

The total variability in the dependent variable,as represented by SS_TOTAL,can be spilt up,or partitioned,into two components: