Question 1

If the assumption of homogeneity of variance is violated a nonparametric test has to be used.

Accepted Answer

A) True 
 B)False

Question 2

What does a t value represent?

Accepted Answer

A t value represents how many estimated

Question 3

Whereas the sum of squares total reflects the total amount of variability in the dependent variable,the sum of squares error reflects the amount of variability that remains before the effects of the dependent variable have been removed.

Accepted Answer

A) True 
 B)False

Question 4

The standard deviation of the sampling distribution of the differences between 2 means is referred to as_________.

Accepted Answer

the standa

Question 5

Dr.Johnson is studying the effects of aspirin on heart rate.He believes that aspirin will lower heart rate.He has 2 groups the treatment group receives 80mg of aspirin for a week (n=4)the control group received a placebo (n=4)and their heart rates are compared.Below is his data in which heart rate is beats per minute.He sets his alpha level at 0.05 and uses a directional test.  
What is Dr.Johnson's critical t-value?

Accepted Answer

A) 1.860 
B) 2.306 
C) 1.943 
D) 1.895 
A) 1.860 
B) 2.306 
C) 1.943 
D) 1.895

Question 6

Dr.Osborn believes that taking calcium will improve bone density in women.She uses a between subjects design and gives the treatment group Calcium everyday and the placebo group a sugar pill.Her scientific or alternative hypothesis is_____.

Accepted Answer

A) non-directional 
B) directional 
C) should not be between subjects 
D) None of these 
A) non-directional 
B) directional 
C) should not be between subjects 
D) None of these

Question 7

Analogous to the standard error of the mean,the size of the standard error of the difference is influenced by two factors: (1)the sample sizes (n1 and n2)and (2)the variability of scores in the populations (ó12 and ó22).

Accepted Answer

A) True 
 B)False

Question 8

_____ represents the proportion of variability in the dependent variable that is not associated with the independent variable--that is,the proportion of variability that is due to disturbance variables.

Accepted Answer

A) eta-squared 
B) 1.00 plus eta-squared 
C) 1.00 minus eta-squared 
D) eta-squared minus 1.00 
A) eta-squared 
B) 1.00 plus eta-squared 
C) 1.00 minus eta-squared 
D) eta-squared minus 1.00

Question 9

Dr.Hansen believes a person taking Tylenol PM will sleep longer but will be drowsier during the day.One group of subjects took.Tylenol (n=5)for 1 month and reported the number of times he or she felt sleepy.The second group was given a placebo (n=5)and asked to log the number of times they felt sleepy with in a month.Sleepy was defined as the urge to sleep or to engage in micro-sleeps at some point in the day.
a.Is there a significant difference between the 2 groups? (Directional and alpha level was set at .05)
   
b.What is the nature of the relationship?
c.What is the strength of the relationship based on eta2?
d.Explain why you used an Independent t-test?

Accepted Answer

a.ANS t=3.77 reject the null the groups

Question 10

The distribution of mean differences across all possible pairs of random samples of a given size represents a sampling distribution of the difference between two independent means.

Accepted Answer

A) True 
 B)False

Question 11

Which of the following is a numerical index that most reflects the influence of disturbance variables?

Accepted Answer

A) SSTOTAL 
B) SSERROR 
C) SSEXPLAINED 
A) SSTOTAL 
B) SSERROR 
C) SSEXPLAINED

Question 12

What is a sampling distribution of the difference between two independent means?

Accepted Answer

A sampling distribution of the differenc

Question 13

According to the homogeneity of variance assumption:

Accepted Answer

A) ó12 + ó22 = ó2 
B) ó12 = ó22 = ó2 
C) ó12 - ó22 = ó2 
D) ó12 = ó22 + ó2 
A) ó12 + ó22 = ó2 
B) ó12 = ó22 = ó2 
C) ó12 - ó22 = ó2 
D) ó12 = ó22 + ó2

Question 14

Dr.Johnson is studying the effects of aspirin on heart rate.He believes that aspirin will lower heart rate.He has 2 groups the treatment group receives 80mg of aspirin for a week (n=4)the control group received a placebo (n=4)and their heart rates are compared.Below is his data in which heart rate is beats per minute.He sets his alpha level at 0.05 and uses a directional test.  
What is the strength of the relationship?

Accepted Answer

A) .75 
B) .72 
C) .67 
D) None of these 
A) .75 
B) .72 
C) .67 
D) None of these

Question 15

The procedure which produces a pooled weighted estimate of the sample variances combines the individual estimates in a manner which is ____.

Accepted Answer

A) proportional to their mean difference 
B) unaffected by sample size 
C) proportional to their degrees of freedom 
D) proportional to the size of difference between the variance estimates 
A) proportional to their mean difference 
B) unaffected by sample size 
C) proportional to their degrees of freedom 
D) proportional to the size of difference between the variance estimates

Question 16

The t statistic approximately follows a t distribution when (1)the samples are independently and randomly selected from their respective populations, (2)the scores in each population are normally distributed,and (3)the scores in the two populations have equal variances.

Accepted Answer

A) True 
 B)False

Question 17

Confidence intervals are used to_____.

Accepted Answer

A) provide information about sampling error 
B) whether of nor a relationship exist between the independent and dependent variables 
C) whether or not homogeneity of variance has been violated. 
D) Both a & b 
E) All of these 
A) provide information about sampling error 
B) whether of nor a relationship exist between the independent and dependent variables 
C) whether or not homogeneity of variance has been violated. 
D) Both a & b 
E) All of these

Question 18

It is important to calculate the _________even if the results indicate there is not a significant difference between groups.

Accepted Answer

eta-square

Question 19

The alternative hypothesis for an independent-groups t test states that _____.

Accepted Answer

A) the two levels of the independent variable are essentially the same 
B) the independent and dependent variables are related 
C) the independent and dependent variables are unrelated 
D) the dependent variable influences the value of the independent variable 
A) the two levels of the independent variable are essentially the same 
B) the independent and dependent variables are related 
C) the independent and dependent variables are unrelated 
D) the dependent variable influences the value of the independent variable

Question 20

The independent groups t test is not robust to any violation of the normality and homogeneity of variance assumptions.

Accepted Answer

A) True 
 B)False

If the assumption of homogeneity of variance is violated a nonparametric test has to be used.

What does a t value represent?

Whereas the sum of squares total reflects the total amount of variability in the dependent variable,the sum of squares error reflects the amount of variability that remains before the effects of the dependent variable have been removed.

The standard deviation of the sampling distribution of the differences between 2 means is referred to as_________.

Dr.Osborn believes that taking calcium will improve bone density in women.She uses a between subjects design and gives the treatment group Calcium everyday and the placebo group a sugar pill.Her scientific or alternative hypothesis is_____.

Analogous to the standard error of the mean,the size of the standard error of the difference is influenced by two factors: (1)the sample sizes (n₁ and n₂)and (2)the variability of scores in the populations (ó₁² and ó₂²).

_____ represents the proportion of variability in the dependent variable that is not associated with the independent variable--that is,the proportion of variability that is due to disturbance variables.

The distribution of mean differences across all possible pairs of random samples of a given size represents a sampling distribution of the difference between two independent means.

Which of the following is a numerical index that most reflects the influence of disturbance variables?

What is a sampling distribution of the difference between two independent means?

According to the homogeneity of variance assumption:

The procedure which produces a pooled weighted estimate of the sample variances combines the individual estimates in a manner which is ____.

The t statistic approximately follows a t distribution when (1)the samples are independently and randomly selected from their respective populations, (2)the scores in each population are normally distributed,and (3)the scores in the two populations have equal variances.

Confidence intervals are used to_____.

It is important to calculate the _________even if the results indicate there is not a significant difference between groups.

The alternative hypothesis for an independent-groups t test states that _____.

The independent groups t test is not robust to any violation of the normality and homogeneity of variance assumptions.

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

If the assumption of homogeneity of variance is violated a nonparametric test has to be used.

What does a t value represent?

Whereas the sum of squares total reflects the total amount of variability in the dependent variable,the sum of squares error reflects the amount of variability that remains before the effects of the dependent variable have been removed.

The standard deviation of the sampling distribution of the differences between 2 means is referred to as_________.

Dr.Osborn believes that taking calcium will improve bone density in women.She uses a between subjects design and gives the treatment group Calcium everyday and the placebo group a sugar pill.Her scientific or alternative hypothesis is_____.

Analogous to the standard error of the mean,the size of the standard error of the difference is influenced by two factors: (1)the sample sizes (n1 and n2)and (2)the variability of scores in the populations (ó12 and ó22).

_____ represents the proportion of variability in the dependent variable that is not associated with the independent variable--that is,the proportion of variability that is due to disturbance variables.

The distribution of mean differences across all possible pairs of random samples of a given size represents a sampling distribution of the difference between two independent means.

Which of the following is a numerical index that most reflects the influence of disturbance variables?

What is a sampling distribution of the difference between two independent means?

According to the homogeneity of variance assumption:

The procedure which produces a pooled weighted estimate of the sample variances combines the individual estimates in a manner which is ____.

The t statistic approximately follows a t distribution when (1)the samples are independently and randomly selected from their respective populations, (2)the scores in each population are normally distributed,and (3)the scores in the two populations have equal variances.

Confidence intervals are used to_____.

It is important to calculate the _________even if the results indicate there is not a significant difference between groups.

The alternative hypothesis for an independent-groups t test states that _____.

The independent groups t test is not robust to any violation of the normality and homogeneity of variance assumptions.

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

Analogous to the standard error of the mean,the size of the standard error of the difference is influenced by two factors: (1)the sample sizes (n₁ and n₂)and (2)the variability of scores in the populations (ó₁² and ó₂²).