Statistics
What is the correct formula for calculating the degrees of freedom for chi-square goodness of fit test? a) n-2 b) k-3 c) n-1 d) k-1
d) k-1
What does r represent in the following statement r(56) = 0.65, p < 0.05? a) critical statistic b) observed statistic c) experimental statistic d) test statistic
d) test statistic
What is a general name for a measure of how data are spread out (or dispersed)? a) skewness b) average c) mean d) variability
d) variability
An "educated guess" that describes the relationship between variables is the ______.
hypothesis
Which of the following is true of a z score that falls below the mean?
it is negative
You should use a Z-test when the population's standard deviation is ______.
known
If you were interested in tracking your GPA during the time you are in graduate school, which of the following might you use?
line graph
In interpreting effect size, what is the meaning of effect size at 0.35?
medium effect size
Generalizability means ______.
results may be applied to the population studied
With five categories for which you are calculating a one-sample chi-square, what are the degrees of freedom? A) 6 B) 3 C) 5 D) 4
D) 4
ANOVA refers to analysis of variance. A) True B) False
A) True
What is the commonly accepted type I error rate in psychological research?
0.05
Which of the following correlations is the weakest?
0.19
What percentage of all scores is represented by the entire normal curve?
100%
What is the inclusive range for this set of scores: 32,15,19,55,22?
41
In a t-test, if the resultant t value is -1.72 and p > 0.05, what is the interpretation? A) There is no significant difference between the sample and the population. B) There is a significant difference between the sample value and the population. C) The answer cannot be determined from the information given. D) The difference is marginal.
A) There is no significant difference between the sample and the population.
An instrument cannot be valid unless it is reliable. A) True B) False
A) True
I once researched the amount of time students studied in my Introduction to Psychology class. Most students students studied a few hours a week (fewer than 4 or 5), but one or two students studied over 20 hours a week (note: this was extreme for the class). What would be the most appropriate measure of central tendency to summarize these data?
?
Participants enrolled in a 2-month long sleep study receive drug 1 for one month, followed by drug 2 for 1 month. Is one drug better at decreasing insomnia than the other?
?
Students at 6 different universities are asked about their attitudes towards vaccinations. Researchers want to see whether there are any differences in attitudes between universities.
?
If there is no difference between the distributions of scores in two groups, what is the effect size equal to? A) 0 B) 2.0 C) 0.5 D) 1.0
A) 0
What is the exclusive range for the following set of scores: 26, 48, 21, 58, 37? A) 37 B) 34 C) 11 D) 21
A) 37
Identify the null hypothesis for testing a relationship. A) H0: ρxy = 0 B) H0: ρxy > 0 C) H1: rxy = 0 D) H1: ρxy > 0
A) H0: ρxy = 0
The first step in testing a hypothesis is ______. A) provide a statement of the null hypothesis B) set the level of significance C) select the appropriate test statistic D) compute the test statistic value
A) provide a statement of the null hypothesis
Why are all ANOVA tests necessarily non-directional?
ANOVA is an omnibus test
What is the one-sample Z-test used to compare? A) the means of two populations B) the mean of a sample to the mean of a population C) the mean of a population to the mean of a sample D) the means of two samples
B) the mean of a sample to the mean of a population
What does the symbol Σ represent? A) an individual score B) the sum of scores C) the mean D) the sample size
B) the sum of scores
What is the obtained value in the equation r(65) = 0.45, p < 0.05? A) 65 B) 0.65 C) 0.45 D) 45
C) 0.45
Which of the following are all types of validity? A) test-retest, parallel, and internal consistency B) dependent, independent, and random C) true score, observed score, and error score D) content, criterion, and construct
D) content, criterion, and construct
An "educated guess" that describes the relationship between variables is the ______. A) research question B) theorem C) postulate D) hypothesis
D) hypothesis
What effect does using "n - 1" in our variance and standard deviation calculations have on our estimates of variability (relative to just "n")? A) it makes our estimate of variability biased B) it standardizes our estimate of variability. C) it makes our estimate of variability smaller D) it makes our estimate of variability larger
D) it makes our estimate of variability larger
What is the formula used to calculate degrees of freedom for a t-test for dependent groups? A) n1 - 1 + n2 B) n1 + n2 - 1 C) n1 + n2 D) n - 1
D) n - 1
The relationship between chocolate sales and student happiness can be tested using the ______.
T statistic
In your study you have 60 respondents identifying their political preference (i.e., Democrat, Republican, or independent). What would the expected frequency be for each category? a) 25 b) 10 c) 15 d) 20
d) 20
Conceptually, what does the F statistic represent?
The ratio of variability between groups relative to variability within groups
Which of the following is an example of a nondirectional hypothesis?
There is a relationship between a high fat diet and weight gain.
How do you interpret the statement z = 2.42, p < 0.05?
There is a significant difference between the sample value and the population.
In a t-test, if the resultant t value is -1.72 and p > 0.05, what is the interpretation?
There is no significant difference between the sample and the population.
When using a t test for dependent means, what is TRUE of the sample?
They are the same group.
In an experiment what type of variable is the treatment (or "manipulated") variable? a) independent variable b) mediating variable c) intervening variable d) dependent variable
a) independent variable
Your goal is to compare the price of gasoline at phoenix gas stations compared to the national average. a) one- sample t-test b) independent- samples t test c) pair-samples t-test d) correlation
a) one- sample t-test
If you posit that a relationship between two variables will be positive, what type of test should you use? a) one- tailed b) ANOVA c) Cohen's d d) two-tailed
a) one-tailed
Approximately what percentage of scores falls between -1 and +1 standard deviations around the mean under the normal curve? a) 95% b) 68% c) 14% d) 34%
b) 68%
In chi-square goodness-of-fit test, when the respondents are almost equally distributed across the categories, the chi-square value will be _________. a) medium b) low c) high d) very high
b) low
Which of the following is most concerned with a measure's relationship to future performance? a) construct reliability b) predictive validity c) concurrent validity d) content reliability
b) predictive validity
What is another way to describe the standard deviation? a) divide variance by n-1 b) square root of variance c) mean range d) squared range
b) square root of variance
There are two ways to decide whether a result is statistically significant. One is to compare your p value with alpha. The second is to compare your test statistic with ____________. a) beta b) the critical value c) the obtained value d) the comparison value
b) the critical value
Imagine that your goal is to identify the most common value in a dataset. Which measure is most appropriate for this task? a) the median b)the mode c) the standard deviation d) variance
b) the mode
Sample size is represented by which of the following? a) y b) n c) X d) M
b)n
If the correlation between variables is 0.60, what percentage of the variance is shared variance? a) 60% b) 30% c) 51% d) 36%
d) 36%
Which of the following is true of z scores that are equal to the mean? a) They are positive b) They are negative c) They are equal to zero d) They are equal to one
c) They are equal to zero
You should use a t-test when the population's standard deviation is a) not relevant b) not calculated c) unknown d) known
c) unknown
Significant correlations are not able to indicate ______.
causality
When a hypothesis posits a difference between groups where the difference is specified, what is this called?
directional hyp
Correlations can be which of the following?
directional or nondirectional
What is the term for the measure of the magnitude of the difference between two groups?
effect size
A correlation coefficient can only test one variable at a time.
false
A test score in the 10th percentile would be considered very high.
false
Sampling error relates to how well a population approximates the characteristics of a sample.
false
I want to know whether the average amount of sleep for our class differs from the general U.S. population. Recent data from Gallup indicated that the mean amount of sleep for Americans is 6.8 hours. They did not report the variability of those scores. What is the appropriate test statistic for this question?
t-test
In the following, what is the meaning of t: t(58) = 5.015, p < 0.01?
test statistic
When a researcher matches participants from different education graduate programs on variables such as age, gender, and a measure of multicultural understanding, the researcher can use a dependent-samples t test in the study. A) True B) False
A) True
Under the normal curve, what percentage of scores, approximately, falls between -1 and +1 standard deviations around the mean? A) 68% B) 14% C) 34% D) 95%
A) 68%
Select the most appropriate statistical test for the following situation: Students at 6 different universities are asked about their attitudes towards vaccinations. Researchers want to see whether there are any differences in attitudes between universities. A) ANOVA B) One-sample t test C) Paired-samples t test D) Independent-samples t test E) Correlation
A) ANOVA
When the research question calls for an examination of the difference in group means among three or more groups, what is the appropriate process? A) Analysis of variance B) Dependent-sample test C) Pearson correlations D) Regression
A) Analysis of variance
When the obtained value is greater than the critical value, what is your decision? A) Reject the null hypothesis. B) Set a higher p value. C) Reject the research hypothesis. D) Accept the null hypothesis.
A) Reject the null hypothesis.
Inferential statistics is based on which of the following? A) The sample is representative of the population. B) The sample is the same size as the population. C) The sample is different from the population. D) The population is smaller than the sample.
A) The sample is representative of the population.
When using a t-test for dependent means, what is TRUE of the sample? A) They are the same group. B) They are observed once. C) There are two different groups. D) There are more than 50.
A) They are the same group.
Correlation coefficients examine relationship between variables. A) True B) False
A) True
Effect size is the magnitude of the differences between groups. A) True B) False
A) True
If you have multiple categories and want to depict the frequency of those categories, you should use a bar chart. A) True B) False
A) True
In the equation t(78) = 1.03, p < 0.01, the number 78 refers to degrees of freedom. A) True B) False
A) True
Nonparametric statistics incorporate fewer assumptions than parametric statistics. A) True B) False
A) True
Probability allows us to determine the exact mathematical likelihood that a difference between groups is due to practice or treatment, as compared with chance or error. A) True B) False
A) True
The nominal level of measurement can be the least precise. A) True B) False
A) True
The nominal level of measurement is defined by categories. A) True B) False
A) True
There are eight steps that you should follow in order to compute and interpret a Z-test statistic manually. A) True B) False
A) True
There is always the possibility of error when making a judgment in statistics. A) True B) False
A) True
Using the coefficient of determination is more precise than using a correlation coefficient alone. A) True B) False
A) True
What kind of error do you make when you reject the null hypothesis when there is actually no difference between groups? A) Type I B) Type II C) Type III D) Power
A) Type I
What is the most commonly used nonparametric test? A) chi-square B) ANOVA C) Whitney-Mann U D) t test
A) chi-square
If you wanted to examine whether the degree of parental involvement differs based on students' grade in school (i.e., 1st, 2nd, 3rd, etc.), what is the dependent variable of interest? A) degree of parent involvement B) grade level C) parents D) students
A) degree of parent involvement
To examine the same group of individuals in two different times, which statistical technique should you select? A) dependent-samples t test B) independent-samples t test C) regression D) analysis of variance
A) dependent-samples t test
Which statistical technique is used to examine one group of subjects under two different conditions? A) dependent-samples t-test B) regression C) independent-samples t-test D) analysis of variance
A) dependent-samples t-test
If you find that the more sleep you get the night before a quiz the higher your test score will be, you have a ______. A) direct correlation B) negative correlation C) indirect correlation D) reverse correlation
A) direct correlation
Correlations can be which of the following? A) directional or nondirectional B) directional only C) neither directional nor nondirectional D nondirectional only
A) directional or nondirectional
What is another term for nonparametric statistics? A) distribution-free statistics B) parametric statistics C) skewed-distribution statistics D) nonnormal statistics
A) distribution-free statistics
What figure is most appropriate for depicting frequencies across a continuous variable? A) histogram B) bar chart C) pie chart D) line graph
A) histogram
You should use a Z-test when the population's standard deviation is ______. A) known B) not calculated C) not relevant D) not known
A) known
What is the general principle of labelling in graph design? A) label everything B) label, but sparingly C) avoid labeling everything D) label in all uppercase letters
A) label everything
In interpreting effect size, what is the meaning of effect size at 0.35? A) medium effect size B) large effect size C) weak effect size D) small effect size
A) medium effect size
What does the n represent in the formula for calculating degrees of freedom for a correlation coefficient? A) number of pairs B) population C) number of groups D sample size
A) number of pairs
If variables change in the same direction, what type of relationship is this called? A) positive correlation B) negative correlation C) negative causation D) positive causation
A) positive correlation
What is the term associated with identifying differences between groups that are very unlikely to occur if the null were true? A) significance B) meaningfulness C) probability D) statistics
A) significance
What does the number 0.01 represent in the following: t(42) = 5.15, p < 0.01? A) significance level B) test statistic C) t value D) degrees of freedom
A) significance level
Imagine that you are publishing a research article. Which measure are your most likely to include? A) standard deviation B) standardized median C) inclusive range D) exclusive range
A) standard deviation
What is used to examine the degree of the relationship between variables? A) hypothesized mean difference B) correlation C) variance D) observations
B) correlation
What type of distribution shows the frequency cases in a class interval along with the number of cases that were below (or less than) that class interval? A) frequency distribution B) cumulative frequency distribution C) midpoint D) frequency polygon
B) cumulative frequency distribution
To examine the same group of individuals in two different times, which statistical technique should you select? A) independent-samples t-test B) dependent-samples t-test C) analysis of variance D regression
B) dependent-samples t-test
When a hypothesis posits a difference between groups where the difference is specified, what is this called? A) research hypothesis B) directional hypothesis C) null hypothesis D) nondirectional hypothesis
B) directional hypothesis
Independent groups are ______. A) continuous B) never related C) always different in size D) related in some way
B) never related
If you wanted to examine the proportion of students in your class who are psychology majors compared to those who are not psychology majors, what type of figure would be best? A) frequency polygon B) pie chart C) ogive D) line graph
B) pie chart
The foundation of inferential statistics is ______. A) algebra B) probability C) linear algebra D) mathematical proofs
B) probability
What is the denominator in the equation for the z value in a one-sample Z-test? A) standard error of the population B) standard error of the mean C) standard error of the median D) standard error of the sample
B) standard error of the mean
Which of the following are all types of reliability? A) true score, observed score, and error score B) test-retest, parallel, and internal consistency C) dependent, independent, and random D) content, criterion, and construct
B) test-retest, parallel, and internal consistency
The measure of central tendency considered the most precise is ______. A) the median B) the mean C) the mode D) the average
B) the mean
When a research hypothesis does not predict the direction of a relationship, the test is ______. A) direct B) two-tailed C) positive D) one-tailed
B) two-tailed
In a simple analysis of variance, how many factor(s) or treatment variables are analysis? A) two or more B) three or more C) only one D) one or more
C) only one
The fact that high-school class rank is highly correlated with college GPA is an example of what type of validity? A) content B) construct C) predictive D) concurrent
C) predictive
What are the three most common measures of variability? A) mean, standard deviation, variance B) mean, median, mode C) range, standard deviation, variance D) mean, range, variance
C) range, standard deviation, variance
Which of the following indicates that the test, scale, or instrument used in research works every time? A) validity B) both reliability and validity C) reliability D) neither validity nor reliability
C) reliability
If measures associated with a test are consistent, then you can conclude that the measure is ______. A) valid B) standard C) reliable D) concurrent
C) reliable
Data for a study is collected from which of the following? A) sampling error B) representative population C) representative sample D) general group
C) representative sample
In interpreting effect size, what is the meaning of effect size at 0.2? A) weak effect size B) large effect size C) small effect size D) medium effect size
C) small effect size
In order to calculate the statistical significance of a correlation coefficient (r), which other test statistic do we use? A) Cohen's d B) η2 C) t test D) F test
C) t test
In the following, what is the meaning of t: t(58) = 5.015, p < 0.01? A) t value B) degrees of freedom C) test statistic D) significance level
C) test statistic
What is another term for the mean in a set of data? A) the midpoint B) the frequency value C) the arithmetic average D) the distribution
C) the arithmetic average
Which measure of central tendency is also known as the midpoint for a set of scores? A) the mode B) the average C) the median D) the mean
C) the median
The null hypothesis refers to which of the following? A) both the sample and the population B) multiple samples C) the population D) the sample
C) the population
Which of the following is calculated by squaring the standard deviation? A) range B) median C) variance D) mean
C) variance
Which of the following is the Greek symbol chi? A) η B) α C) χ D) β
C) χ
"Bear cubs born in the northern woods will have thicker fur than bear cubs born in the southern woods." This is an example of which of the following?
Directional hyp
What is the meaning of the term SEM in the formula for calculating a z score? A) standard error of the mean B) standard error of the median C) standard error of measurement D) standard error of movement
A) standard error of the mean
When you fold a normal cure, each half fits perfectly on top of the other, a characteristic known as ______. A) symmetry B) asymptotic C) probability D) variability
A) symmetry
In order to determine whether you will reject the null hypothesis, with what must the test statistic be compared? A) the critical value B) the significance level C) the p-value D) the obtained value
A) the critical value
What would be your preferred measure of central tendency if you had the following data: $21,550; $23,750; $24,700; $27,550; $29,275? A) the mean B) the median C) the mode D) the standard deviation
A) the mean
Correlation coefficients examine ______. A) the relationship between variables B) differences between two or more groups C) differences between two groups D) how variables can be arranged into higher-order factors
A) the relationship between variables
A correlation coefficient is a numerical index that reflects the relationship between ______. A) two variables B) two hypotheses C) a variable and a sample D) three variables
A) two variables
Which standard score indicates the number of standard deviations from the mean? A) z score B) x score C) T score D) IQ score
A) z score
In class we talked a lot about how psychologists measure concepts that don't have well defined measurements (e.g., trauma or depression). When we develop a new instrument to measure one of these concepts, what is the overarching type of validity that we hope to have? A) content validity B) construct validity C) predicative validity D) concurrent validity
B) construct validity
An investigator is interested in the effects of stress on reaction time. She gives a reaction time test to three groups of subjects: one group that is under a great deal of stress, one group under a moderate amount of stress, and a third group that is under almost no stress.
ANOVA
What statistical analysis produced the following result: F (2, 57) = 10.80, p < 0.01?
ANOVA
What is the median for the following amounts: $93,000; $18,560; $86,400; $62,550; $43,340? A) $93,000 B) $62,550 C) $86,400 D) $43,340
B) $62,550
What is the commonly accepted type I error rate in psychological research? A) 0.20 B) 0.05 C) 0.10 D) 0.50
B) 0.05
When the amount of variability due to within-group differences is equal to the amount of variability due to between-group differences, what is the F value? A) 2 B) 1 C) 0 D) -1
B) 1
If the sample mean is 100, the population average is 90, and the standard error of the mean is 10, what is the observed z value? A) -1.0 B) 1.0 C) 0 D) 0.01
B) 1.0
Why are all ANOVA tests necessarily non-directional? A) Because correlations are the only statistic that can tell us about direction B) ANOVA is an omnibus test C) ANOVA is based on absolute values D) Only factorial ANOVA can make directional hypotheses
B) ANOVA is an omnibus test
A correlation coefficient can only test one variable at a time. A) True B) False
B) False
A good hypothesis is stated as a question. A) True B) False
B) False
A test score in the 10th percentile would be considered very high. A) True B) False
B) False
If you have multiple categories and want to depict the proportion of cases in those categories, a line chart is most appropriate. A) True B) False
B) False
In hypothesis testing, the test statistic must be compared against the obtained value. A) True B) False
B) False
It is advisable to use every feature a computer program has to create charts and graphs of your data. A) True B) False
B) False
It is more desirable to find a positive correlation than a negative correlation. A) True B) False
B) False
It is possible to control for every possible factor in a research study. A) True B) False
B) False
Sample size is used when computing effect size. A) True B) False
B) False
The normal curve is not always symmetrical. A) True B) False
B) False
The observed score is equal to the true score minus the error score. A) True B) False
B) False
The one-sample chi-square focuses on the distribution of two variables. A) True B) False
B) False
The three measures of central tendency--the mean, median, and mode--are all interchangeable. A) True B) False
B) False
When two variables have an especially strong correlation (e.g., r > .7), that indicates the two variables have a causal relationship. A) True B) False
B) False
When you perform multiple t tests, you increase the Type II error rate higher than an acceptable rate A) True B) False
B) False
Which of the following is an example of a null hypothesis for testing a correlation coefficient? A) H1: ρxy = 0 B) H0: ρxy = 0 C) H0: ρxy > 0 D) H1: ρxy > 0
B) H0: ρxy = 0
Which of the following represents a research/alternative hypothesis? A) H1: X1 = X2 B) H1: μ1 > μ2 C) H1: X1 < μ2 D) H0: μ1 = μ2
B) H1: μ1 > μ2
What type of correlation should you use to compute the correlation between two ordinal-level variables? A) Pearson B) Spearman's rank C) point biserial D) phi
B) Spearman's rank
What is the first step in the computation of the F statistic? A) Select the appropriate test B) State the null and research hypothesis C) Set the level of risk D) Compute the obtained value
B) State the null and research hypothesis
an unmeasured third variable that explains a relationship between two other variables is called A) a dependent variable B) a confounding variable C) an independent variable D) an ordinal variable
B) a confounding variable
What percentage of all scores fall above a z score of +1? A) 34% B) 68% C) 16% D) 50%
C) 16%
An example of skew is most clearly represented in which of the following sets of data? A) 250, 283, 300, 267, 289 B) 3, 4, 6, 7, 9 C) 19, 27, 32, 50, 147 D) 12, 13, 15, 17, 19
C) 19, 27, 32, 50, 147
Which of the following is an example of a design that examines the effects of gender and socioeconomic status (i.e., high, medium, and low) on a test of student achievement? A) 3 X 3 ANOVA B) simple ANOVA C) 2 X 3 ANOVA D) one-way ANOVA
C) 2 X 3 ANOVA
What is the inclusive range for this set of scores: 32,15,19,55,22? A) 40 B) 5 C) 41 D) 6
C) 41
What percentage of scores fall on either side of the normal curve distribution? A) 34% B) 99% C) 50% D) 68%
C) 50%
Select the most appropriate statistical test for the following situation: An investigator predicts that individuals that fit the Type A Behavior Pattern (highly competitive and time conscious) will have higher scores on a questionnaire measure of need for achievement than individuals that fit the Type B Behavior pattern (absence of Type qualities). The investigator collects need for achievement scores from 10 Type A subjects and 10 Type B subjects. Higher scores reflect greater levels of need for achievement. A) Correlation B) ANOVA C) Independent-samples t test D) One-sample t test E) Paired-samples t test
C) Independent-samples t test
Select the most appropriate statistical test for the following situation: Participants enrolled in a 2-month long sleep study receive drug 1 for one month, followed by drug 2 for 1 month. Is one drug better at decreasing insomnia than the other? A) ANOVA B) One-sample t test C) Paired-samples t test D) Independent-samples t test E) Correlation
C) Paired-samples t test
What is an appropriate conclusion to draw from the following statistic: F(2, 27) = 8.80, p < 0.05? A) 27 people participated in this study B) Group 1 was statistically different from group 2 C) Reject the null hypothesis D) There was a total difference of 8.80 between all means
C) Reject the null hypothesis
After establishing the null hypothesis, what is the next step in the application of a statistical test? A) Compare critical values. B) Determine the critical value needed for rejection of the null hypothesis. C) Set the level of significance. D) Compute the test statistic value.
C) Set the level of significance.
When you do not reject the null hypothesis and it is actually false, what kind of error do you make? A) Power B) Type III C) Type II D) Type I
C) Type II
If your current examination mean is 97.2 and you receive a 99 on the next examination, what effect will this have? A) Your mean is unchanged. B) Your mean will decrease. C) Your mean will increase. D) More information is needed to determine.
C) Your mean will increase.
Compared with a 99% confidence interval, a 95% confidence interval would result in which of the following? A) a range that cannot be determined in the confidence interval B) the same range of values in the confidence interval C) a smaller range of values in the confidence interval D) a wider range of values in the confidence interval
C) a smaller range of values in the confidence interval
If you cannot establish reliability and validity, then your results ______. A) must be true B) are valid only in some circumstances C) are inconclusive D) must be interpreted
C) are inconclusive
What will the chi-square value be when there is almost no difference between what is observed and what is expected? A) close to 1 B) close to -1 C) close to 0 D) 1
C) close to 0
The Pearson's correlation coefficient examines variables that are ______ in nature. A) categorical B) not continuous C) continuous D) not categorical
C) continuous
What type of descriptive statistic would you want to use to examine how the number of pets is related to psychological wellbeing? A) variance B) standard deviation C) correlation D) mean
C) correlation
To compute the test statistic or t value, what must first be calculated to approximate the sample size? A) standard deviation B) mean score C) degrees of freedom C) pooled variance
C) degrees of freedom
It addition to true score, what else contributes to an individual's observed score on a measure? A) reliable score B) expected score C) error score D) predicted score
C) error score
Name the most basic method of illustrating data. A) polygon B) line chart C) frequency distribution D) pie chart
C) frequency distribution
Which technique is used to generalize findings from the sample to the population? A) descriptive statistics B) qualitative analysis C) inferential statistics D) nonparametric statistics
C) inferential statistics
In order to calculate the standard deviation, what must you calculate first? A) mode B) variance C) mean D) median
C) mean
I once researched the amount of time students studied in my Introduction to Psychology class. Most students students studied a few hours a week (fewer than 4 or 5), but one or two students studied over 20 hours a week (note: this was extreme for the class). What would be the most appropriate measure of central tendency to summarize these data? A) arithmetic mean B) mode C) median D) mean
C) median
When there is no difference between sample and population values, what do you have? A) a high but positive sampling error B) a low but positive sampling error C) no sampling error D) a high sampling error
C) no sampling error
What is the term for statistics that are not governed by distributions? A) parametric B) population C) nonparametric D) nondistribution
C) nonparametric
The actual or measured score you receive is known as the ______. A) real score B) true score C) observed score D) error score
C) observed score
In a one sample Z-test, how many groups are compared? A) four B) two or more C) one D) three
C) one
The t test for independent means is used when each group is tested ______. A) any number of times B) only twice C) only once D) once or twice
C) only once
What is the range of possible values of the Pearson's product-moment correlation coefficient? A) -2.0 to 2.0 B) -0.01 to +0.01 C) -2.0 to 1.0 D) -1.0 to 1.0
D) -1.0 to 1.0
What is the level of significance associated with the null hypothesis generally set at? A) 0.20 B) 0.001 C) 0.10 D) 0.05
D) 0.05
What is the sample size in a t-test for dependent means when the degrees of freedom is 24? A) 20 B) 26 C) 24 D) 25
D) 25
What is the standard used by statisticians to determine the probability of something occurring outside of chance alone? A) 99% B) 75% C) 0.05% D) 5%
D) 5%
What is the expected frequency for each category when you have 100 respondents identifying their gender? A) 25 B) 33 C) 75 D) 50
D) 50
There are 32 participants in Group 1 and 30 participants in Group 2. What is the associated degrees of freedom? A) 58 B) 62 C) 59 D) 60
D) 60
What statistical analysis produced the following result: F (2, 57) = 10.80, p < 0.01? A) Paired-samples t test B) Correlation C) Independent-samples t test D) ANOVA
D) ANOVA
Imagine you have calculated a one-tailed statistical test where p = .07. What is the correct decision? A) Accept the alternative hypothesis B) Prove the null hypothesis C) Reject the null hypothesis D) Fail to reject the null hypothesis
D) Fail to reject the null hypothesis
A normal curve has which of the following characteristics? A) Mean, median, and mode are different. B) Mean and median are the same, but the mode is different. C) Mean and mode are the same, but the median is different. D) Mean, median, and mode are the same.
D) Mean, median, and mode are the same.
Conceptually, what does the F statistic represent? A) The total amount of difference between group means B) Alpha C) The correlation between an independent variable and a dependent variable D) The ratio of variability between groups relative to variability within groups
D) The ratio of variability between groups relative to variability within groups
Which of the following is an example of a nondirectional hypothesis? A) There is a negative relationship between a high fat diet and weight gain. B) There is no relationship between a high fat diet and weight gain. C) There is a positive relationship between a high fat diet and weight gain. D) There is a relationship between a high fat diet and weight gain.
D) There is a relationship between a high fat diet and weight gain.
How do you interpret the statement z = 2.42, p < 0.05? A) The answer cannot be determined from the information given. B) There is a marginally significant difference between the sample value and the population. C) There is no significant difference between the sample value and the population. D) There is a significant difference between the sample value and the population.
D) There is a significant difference between the sample value and the population.
Correlation coefficients are used to describe which of the following? A) individuals B) depends on the correlation used C) individuals as well as a group D) a group
D) a group
What does the correlation coefficient measure? A) prediction B) causation C) mean differences D) association
D) association
The ______ is the value that best represents an entire group of scores. A) mode B) median C) mean D) average
D) average
Which of the following is another name for the normal curve? A) asymptotic B) symmetry C) probability D) bell-shaped curve
D) bell-shaped curve
The term associated with the upper or lower boundary of a set of scores used in the creation of a frequency distribution is ______. A) histogram B) frequency interval C) polygon D) class interval
D) class interval
What type of hypothesis suggests that sets of variables are equal? A) directional hypothesis B) research hypothesis C) nondirectional research hypothesis D) null hypothesis
D) null hypothesis
Select the appropriate statistical test for the following situation: Your goal is to compare the weight of 14 patients before and after open-heart surgery. A) one-sample t test B) correlation C) independent-samples t test D) paired-samples t test
D) paired-samples t test
Select the most appropriate statistical test for the following situation: Your goal is to compare the the weight of 14 patients before and after open-heart surgery. A) correlation B) one-sample t test C) independent-samples t test D) paired-samples t test E) ANOVA
D) paired-samples t test
If you wanted to examine the proportion of students in your class who are male compared to female, which of the following might you use? A) line graph B) frequency distribution C)polygon D) pie chart
D) pie chart
Which of the following is the simplest measure of variability to calculate? A) median B) standard deviation C) mean D) range
D) range
A(n) ______ difference is likely due to some systematic influence and unlikely to be due to sampling error. A) serendipitous B) null C) insignificant D) significant
D) significant
A researcher examined the effect of study strategies on test performance. What is the dependent variable? A) the researcher B) study strategies C) differences D) test performance
D) test performance
If I have an individual complete a measurement (e.g., a personality scale) at two different times, what kind of reliability am I most likely trying to calculate? A) internal consistency reliability B) similar-forms reliability C) parallel-forms reliability D) test-retest reliability
D) test-retest reliability
In a simple analysis of variance, what does the term "simple" indicate? A) that it uses factorial correlation B) that there are fewer than 10 participants C) that testing takes less than 24 hours D) that participants are grouped and compared in only one way
D) that participants are grouped and compared in only one way
In the result X2(3) = 8.4, p < 0.05, what is X2? A) the critical value B) the obtained value C) the significance level D) the chi-square statistic
D) the chi-square statistic
The level of significance is determined by which of the following? A) the results B) the participants C) the study sponsors D) the researchers
D) the researchers
The t-test for dependent means is used when your sample is tested ______. A) one time B) one or more times C) two or more times D) two times
D) two times
What type of alternative hypothesis is indicated by the following research question: Is there a relationship between food consumption and post-meal sleepiness? A) valid hypothesis B) invalid hypothesis C) one-tailed hypothesis D) two-tailed hypothesis
D) two-tailed hypothesis
The term used to describe how much scores differ from one another is ______. A) mode B) median C) mean D) variability
D) variability
Imagine you have calculated a one-tailed statistical test where p = .07. What is the correct decision?
Fail to reject the null hypothesis
Sampling error relates to how well a population approximates the characteristics of a sample. True False
False
Which of the following represents a null hypothesis?
H0: μ1 = μ2
How many observations are there for each case in a t test for dependent samples?
two
What type of alternative hypothesis is indicated by the following research question: Is there a relationship between food consumption and post-meal sleepiness?
two-tailed hyp
When you do not reject the null hypothesis and it is actually false, what kind of error do you make?
type II
Which of the following represents a nondirectional research hypothesis? a) H1: μ1 > μ2 b) H0: X1 ≠ X2 c) H1: X1 < X2 d)H1: μ1 ≠ μ2
d) H1: μ1 ≠ μ2
Your goal is to compare the the weight of 14 patients before and after open-heart surgery.
paired-samples t test
Imagine you have calculated a one-tailed statistical test where p = .02. What is the correct decision?
reject the null hyp
If I have an individual complete a measurement (e.g., a personality scale) at two different times, what kind of reliability am I most likely trying to calculate?
test-retest reliability
Correlation coefficients examine relationship between variables.
true
Effect size is the magnitude of the differences between groups (T/F)
true
When a researcher matches participants from different education graduate programs on variables such as age, gender, and a measure of multicultural understanding, the researcher can use a dependent-samples t test in the study.
true
The research question in this study was whether individuals would rate the intellect of an "applicant" differently when they heard a job pitch than when they read a job pitch. To answer this question the authors randomly assigned 39 professional recruiters for Fortune 500 companies to one of two conditions. In the audio condition, participants listened to audio recordings of a job candidate's spoken job pitch. In the transcript condition, participants read a transcription of the job candidate's pitch. What is the independent variable in this example?
type of job pitch
