Multiple choice question | Numerical analysis homework help
In the t test for independent groups, ____.
we estimate µ1 µ2
we estimate 2
we estimate X1-X2
df = N 1
Exhibit 14-1
A professor of women’s studies is interested in determining if stress affects the menstrual cycle. Ten women are randomly sampled for an experiment and randomly divided into two groups. One of the groups is subjected to high stress for two months while the other lives in a relatively stress-free environment. The professor measures the menstrual cycle (in days) of each woman during the second month. The following data are obtained.
High stress
20
23
18
19
22
Relatively stress free
26
31
25
26
30
Refer to Exhibit 14-1. The obtained value of the appropriate statistic is ____.
tobt = 4.73
tobt = 4.71
tobt = 3.05
tobt = 0.47
Refer to Exhibit 14-1. The df for determining tcrit are ____.
4
9
8
3
Refer to Exhibit 14-1. Using = .052 tail, tcrit = ____.
+2.162
+2.506
±2.462
±2.306
Refer to Exhibit 14-1. Using = .052 tail, your conclusion is ____.
accept H0; stress does not affect the menstrual cycle
retain H0; we cannot conclude that stress affects the menstrual cycle
retain H0; stress affects the menstrual cycle
reject H0; stress affects the menstrual cycle
Refer to Exhibit 14-1. Estimate the size of the effect. = ____
0.8102
0.6810
0.4322
0.5776
A major advantage to using a two condition experiment (e.g. control and experimental groups) is ____.
the test has more power
the data are easier to analyze
the experiment does not need to know population parameters
the test has less power
Which of the following tests analyzes the difference between the means of two independent samples?
correlated t test
t test for independent groups
sign test
test of variance
If n1 = n2 and n is relatively large, then the t test is relatively robust against ____.
violations of the assumptions of homogeneity of variance and normality
violations of random samples
traffic violations
violations by the forces of evil
Exhibit 14-3
Five students were tested before and after taking a class to improve their study habits. They were given articles to read which contained a known number of facts in each story. After the story each student listed as many facts as he/she could recall. The following data was recorded.
Before
10
12
14
16
12
After
15
14
17
17
20
Refer to Exhibit 14-3. The obtained value of the appropriate statistic is ____.
3.92
3.06
4.12
2.58
Refer to Exhibit 14-3. What do you conclude using = 0.052 tail?
reject H0; the class appeared to improve study habits
retain H0; the class had no effect on study habits
retain H0; we cannot conclude that the class improved study habits
accept H0; the class appeared to improve study habits
Which of the following is (are) assumption(s) underlying the use of the F test?
the raw score populations are normally distributed
the variances of the raw score populations are the same
the mean of the populations differ
the raw score populations are normally distributed and the variances of the raw score populations are the same
If its assumptions are met, the analysis of variance technique is appropriate when ____.
two or more factors are varied
several levels of a single independent variable are compared
three or more groups are involved
all of the other three options
A major limitation of a two group design is that ____.
we can’t run enough subjects
very often, two groups are insufficient for a clear interpretation
the population parameters may not be applicable
the means between groups may not differ
sB2 is a measure of ____.
2 alone
2 + the effects of the independent variable
the variability between the means
2 + the effects of the independent variable and the variability between the means
The total degrees of freedom for an experiment with n1 = 10, n2 = 12, and n3 = 10 is ____.
2
32
31
29
Exhibit 15-3
Pertain to the following data.
Refer to Exhibit 15-3. What is the value of Fobt?
5.67
6.53
1.95
3.26
Refer to Exhibit 15-3. What is the value of Fcrit ? Use = 0.05.
5.14
4.76
4.46
4.07
Refer to Exhibit 15-3. What is your conclusion? Again use = 0.05
retain H0
reject H1
reject H0
accept H0
Refer to Exhibit 15-3. Using , the estimated size of effect is ____.
22.6% of the variability
52.8% of the variability
43.6% of the variability
55.1% of the variability
Refer to Exhibit 15-3. Using 2, what is the estimated size of effect?
0.7232
0.6852
0.6582
0.6312
What is the value of SST if SSB = 236 and SSW = 54?
290
182
4.37
100
By doing multiple t tests when there are more than 2 experimental groups we increase the risk of making what kind of mistake?
accepting H0
Type I error
Type II error
all of the other three options
If = 46, = 50, = 92 and n1 = n2 = n3, what is the value of ?
cannot be determined from information given
50.0
188.0
62.67
If SSW = 126, N = 28, k = 4, then what is the value of sW2
cannot be determined from information given
5.25
42.0
4.667
If dfB = 3 and dfT = 29 and Fobt = 3.15, what would you conclude using = 0.05?
reject H0
reject H1
retain H0
retain H1
If sB2 = 27.9 and sW2 = 54.2, what is the value of Fobt?
impossible result, there must be an error
1.94
0.51
2.76
A priori comparisons ____.
are planned in advance of the experiment
often arise out of theory and prior research
may be done without obtaining a significant Fobt in the one-way ANOVA
all of the other three options
Chi-square is used to test differences between ____.
proportions
means
variances
none of the other three options
The sampling distribution of chi-square is ____.
skewed
varies with df
is a theoretical distribution
all of the other three options
A contingency table ____.
is a two-way table
involves two variables
involves two mutually exclusive variables
is a two-way table and involves two variables
The computation of fe ____.
is based on population proportion estimates
is based on known population proportions
is based on population means
none of the other three options
If N = 18 and = 0.052 tailed, the value of Tcrit is ____.
40
39
41
47
If = 0.05, and df = 4, the value of 2crit = ____.
9.488
0.711
7.815
11.070
Exhibit 17-1
Prior to a recent gubernatorial election, a survey was conducted to determine whether there was a relationship between sexual gender and preference for the Democratic or Republican candidate. The following data were recorded.
Refer to Exhibit 17-1. The value of 2obt = ____.
2.06
2.09
1.80
1.75
Refer to Exhibit 17-1. The value of df = ____.
2
1
3
need more information
Refer to Exhibit 17-1. Using = 0.05, 2crit = ____.
3.841
5.412
2.706
3.841
Refer to Exhibit 17-1. Using = 0.05, what is your conclusion?
accept H0; there is no relationship between sex and candidate preference
reject H0; there is a significant relationship between sex and candidate preference
retain H0; the study does not show a significant relationship between sex and candidate preference
retain H0; this study shows a significant relationship between sex and candidate preference
As the separation between the two groups of scores increases, Uobt ____.
increases
decreases
stays the same
approaches Uobt
The statistics (U or U’) used in the Mann-Whitney U test, measure ____.
the differences between the means of the two groups
the direction of the differences between pairs of scores
the power of the experiment
the separation between the two groups
If n1 = 6, n2 = 8 and = 0.052 tail, Ucrit value is ____.
8
40
6
42
The Mann-Whitney U test is used with ____.
an independent groups design
a replicated measures design
a correlated groups design
none of the other three options
Using SPSS, the appropriate steps to analyze data for student’s t test for correlated groups are _________
Compare Means > Paired Sample t test > Before_C > After_C
Analyze > Compare Means > Paired Sample t test > After_C > Before_C
Analyze > Compare Means > Paired Sample t test > Before_C > After_C
Analyze > Compare Means > Before_C > After_C
In SPSS, the results of analysing data for student’s t test are displayed ____.
in a graph
in a number of tables
as a stem and leaf
in a histogram
In SPSS, the appropriate steps to analyze data for a one-way ANOVA are ____.
you cannot perform ANOVA in SPSS
One-Way ANOVA >Analyze > Compare Means
Compare Means > One-Way ANOVA
Analyze > Compare Means > One-Way ANOVA
In SPSS, when you follow the steps to perform one-way ANOVA, ____.
you will not be given the option to compute “descriptive statistics”
you will be given the option to compute “descriptive statistics”
you will be given the option to compute “descriptive statistics”, but you have to open a new file
you will be given the option to compute “descriptive statistics”, but you have to restart SPSS