Ch. 14

power

Probability of rejecting a false null hypothesis (or, the probability of detecting a significant effect in a sample if an effect is significant in a population)

Which of the following is an example of a measure of effect size that described the size of a shift in a population as the number of standard deviations that scores shifted? a. Cohen's d b. Eta-squared c. Cramer's V d. Coefficient of determination

a. Cohen's d

The coefficient of determination is used as an estimate of effect size for which null hypothesis significance test? a. Correlation b. Chi-square test c. t-test d. ANOVA

a. Correlation

When a parametric test is used to analyze data, which of the following research designs, if applied correctly, will then have established both statistical control and experimental control of individual error variation? a. Experimental b. Nonexperimental c. Quasi-experimental d. Case study

a. Experimental

Which of the following tests is a non-parametric alternative for a test in which the same participants are observed in each of three or more groups? a. Friedman test b. Kruskal-Wallis H test c. Mann-Whitney U test d. Wilcoxon Signed-Ranks T test

a. Friedman test (within subjects)

A statistical procedure used to determine whether observed frequencies at each level of one categorical variable are similar to or different from frequencies expected, is called the chi-square: a. goodness-of-fit test. b. test for independence. c. test for ordinal data. d. correlation coefficient.

a. goodness-of-fit test.

If a researcher decides to RETAIN the null hypothesis, then the decision was that: a. an effect reached significance. b. an effect failed to reach significance. c. an effect is small. d. an effect is large.

b. an effect failed to reach significance.

To apply NHST, we state a null hypothesis, and then set a criterion upon which we will decide to: a. retain or accept the null hypothesis. b. retain or reject the null hypothesis. c. accept or reject the null hypothesis. d. retain or reject the alternative hypothesis.

b. retain or reject the null hypothesis.

The denominator for each estimate of Cohen's d is: a. sample mean difference. b. sample standard deviation. c. standard error. d. proportion of variance.

b. sample standard deviation.

A statistical procedure used to determine whether frequencies observed at the combination of levels of two categorical variables are similar to frequencies expected, is called the chi-square: a. goodness-of-fit test. b. test for independence. c. analysis of variance. d. correlation coefficient.

b. test for independence.

A researcher evaluates preference for each of three advertisements aimed at children. He asks 60 parents to choose their favorite advertisement and records their choice. What type of analysis is appropriate for this research design? a. One-way analysis of variance b. Three-way analysis of variance c. Chi-square goodness-of-fit test d. Chi-square test for independence

c. Chi-square goodness-of-fit test

Which of the following words best describes certainty? a. Inferential b. Significance c. Confidence d. Precision

c. Confidence

A measure of proportion of variance that is used as an estimate of effect size for the chi-square test for independence, is called: a. eta-squared. b. Cohen's d. c. Cramer's V. d. coefficient of determination.

c. Cramer's V.

The coefficient of determination is mathematically equivalent to what other measure of proportion of variance? a. Cohen's d b. Cramer's V c. Eta-squared d. Omega-squared

c. Eta-squared

What formula is computed to determine the likelihood or probability of obtaining a sample outcome, if the value stated in the null hypothesis is true? a. Effect size b. Confidence interval c. Test statistic d. Bayes' theorem

c. Test statistic (computes a p value)

If a researcher obtains a null finding, then what is the decision? a. The researcher correctly rejected the null hypothesis b. The researcher incorrectly rejected the null hypothesis c. The researcher correctly retained the null hypothesis c. The researcher failed to make a decision

c. The researcher correctly retained the null hypothesis

wider intervals

higher confidence (higher confidence interval) and lower precision (they have an inverse relationship)

State 3 assumptions that must be met to conduct a parametric test with a set of data?

interval/ratio equal variances the data are normally distributed in population

p-value

likelihood of statistical result in a sample if null hypothesis were true in a population (or likelihood of a statistically significant result by chance)

two way within subjects ANOVA

one way: one independent variable two way: two independent variables (race and gender on sleep problems)

Two Way between Subjects Design (fruit)

two independent variables the interaction between variables is multiplicative (the whole is greater than the sum of the parts) proximity and visibility of fruit were manipulated (different participants in each cell or group)

Two Way within Subjects Design (fruit)

variability of food and arrangement of food were manipulated (same subjects observed in each cell or group)

In a research study, one group of tasters was asked to taste and rate the sweetness of four different energy drinks on an interval scale measure. State the appropriate parametric text used to analyze these data?

within subjects ANOVA

t tests

(cohen's d) its value represents the number of standard deviations that scores shift or fall above or below a value stated in a null hypotesis

ANOVAs

(n^2) its value represents the proportion of variance in a dependent variable that can be explained by the levels of a factor

Phi

--- used when both variables are nominally-coded

Criterion for Determining Statistical Significance

1) alpha or p-value: probability of obtaining a statistic from a sample if the null hypothesis is true 2) custom criterion for most behavioral science studies is .05 or 5% 3) when the likelihood of obtaining a sample outcome is less than 5% if the null hypothesis were true, "we reject the null hypothesis" (or infer the sample differs significantly from the population) 4) when the likelihood of obtaining a sample outcome is greater than 5% if the null hypothesis were true, "we retain the null hypothesis" (or infer the sample does not differ significantly from the population)

parametric test

1) used to test hypotheses about parameters in the population 2) these tests assume data are interval or ratio 3) these tests assume data are normally distributed 4) most variables examined in the behavioral sciences are approximately normally distributed; most of the tests are "robust" to some violations of the normal distribution assumption 4) these test assume variances between groups are approximately equal 5) large focus on mean scores --- unbiased estimator of population mean

A health psychologist compares the number of students who are lean, overweight, or obese at a local school to expected proportions in each category. What type of chi-square test would he use (chi-square test of independence or goodness of fit)?

Goodness of fit

inferential statistics

Inferences made from samples to the population (i.e., can results from sample be generalized to the population?) Includes a variety of statistical tests

Regression

Scale of measurement and # of predictor variables

chi-square test for independence

Statistical procedure used to determine whether frequencies observed at the combination of levels of two categorical variables are similar to or different from frequencies expected

chi-square goodness-of-fit test

Statistical procedure used to determine whether observed frequencies at each level of one categorical variable are similar to or different from frequencies expected 1) lunch preferences: sandwich, pizza, burrito, noodle dish, other 2) frequencies: department in college with most majors (ONE VARIABLE)

What type of error (Type I or Type II) is associated with the decision to reject the null hypothesis?

Type I

Interval Estimation

1) The interval is a range of possible values within which an unknown population parameter is likely to be contained 2) Level of confidence: The probability or likelihood that an interval estimate will contain the value of an unknown population parameter (e.g., a population mean) 3) Confidence Interval (CI) states range of possible values for a population parameter

Effect Size

A statistical measure of the size or magnitude of an observed effect in a population, which allows researchers to describe how far scores shifted in a population, or the percent of variance in a DV that can be explained by the levels of a factor

A researcher rejects the null hypothesis using a chi-square test of independence. Does this decision mean that two factors are independent or related?

Related

point estimation

a sample statistic (sample mean) is used to estimate a population parameter (population mean) limits are set for the possible values of a population parameter within which the parameter is likely to be contained

The Spearman, Point-biserial, and phi correlation coefficients are mathematically equivalent to the ________ correlation coefficient. a. Pearson b. chi-square c. regression d. universal

a. Pearson

A researcher reports that the value of a null hypothesis is contained within a 95% CI for that data. What then would have been the decision for a hypothesis test at a .05 level of significance? a. Retain the null hypothesis b. Reject the null hypothesis c. Not enough information to make a decision d. Too much information to make a decision

a. Retain the null hypothesis

A researcher computes a test statistic and finds that the p-value for this test is .03. What does this result mean? a. There is a 3% likelihood of obtaining the test statistic value, if the null were true. b. The probability of committing a Type I error if we retain the null hypothesis is 3%. c. The probability of committing a Type II error if we reject the null hypothesis is 3%. d. There is a 3% likelihood that the researchers hypothesis is correct.

a. There is a 3% likelihood of obtaining the test statistic value, if the null were true.

Procedures used that allow researchers to generalize observations made with samples to the larger population from which they were selected, is called: a. inferential statistics. b. descriptive statistics. c. summary statistics. d. illustrative statistics.

a. inferential statistics.

The criteria for a decision regarding the value stated in a null hypothesis is set by the: a. level of significance. b. p-value. c. t-statistic. d. type of research design.

a. level of significance.

A statement about a population parameter, such as the population mean, that is assumed to be true, is called: a. null hypothesis. b. alternative hypothesis. c. researchers' hypothesis. d. significance hypothesis.

a. null hypothesis.

We observe ____ categorical factor(s) in a chi-square goodness-of-fit test; we observe ____ categorical factor(s) in a chi-square test for independence. a. one; two b. two; one c. one; two or more d. two or more; one

a. one; two

true

accept null hypothesis when null hypothesis is actually true

If a researcher finds that the coefficient of determination for a set of data is equal to .12, then what is the value of eta-squared for this set of data? a. .01 b. .12 c. .24 d. not enough information

b. .12

A researcher computes a correlation coefficient equal to .40. What then is the coefficient of determination for this correlation? a. .04 b. .16 c. .40 d. .80

b. .16

Which of the following is an example of a measure of proportion of variance? a. Cohen's d b. Cramer's V c. Estimation d. Significance

b. Cramer's V

If many groups are observed, then parametric tests also make the assumption that the variance in the population for each group is: a. positively skewed. b. about the same or equal. c. associated with large variance. d. prone to errors in the data.

b. about the same or equal.

A researcher decides at a .05 level of significance to reject the null hypothesis that the value of a populaiton mean is equal to 12. Which of the following CIs is consistent with this conclusion? a. 95% CI 11, 13 b. 95% CI 8, 12 c. 95% CI 9, 11 d. 95% CI 11.5, 12.5

c. 95% CI 9, 11

Two researchers identify an effect in a population. Researcher A reports Cohen's d = .09 and Researcher B reports Cohen's d = .19. Which researcher reports a small effect size based on Cohen's conventions? a. Researcher A b. Researcher B c. Both researchers report a small effect size d. None of the researchers report a small effect size

c. Both researchers report a small effect size

Which of the following is an example of a non-parametric test? a. Analysis of variance b. The t-tests c. Chi-square test d. Pearson correlation

c. Chi-square test

If a researcher records the correlation between happiness (high, low) and relationship status (short-term, long-term), then which correlation measure is most appropriate for this analysis? a. Spearman b. Point-biserial c. Phi d. Significance

c. Phi

A researcher identifies the following conclusion: "The data show the number of patients who complete counseling depends on, or is related to, whether a patient participated in family or individual counseling sessions." What type of chi-square test was computed in this example? a. Factorial analysis of variance b. Goodness-of-fit test c. Test for independence d. Either b or c could be correct

c. Test for independence

A researcher directly controls for the probability of a ________, but does not directly control the probability of a ________. a. Type I error; alpha level b. Type II error; beta level c. Type I error; Type II error d. Type II error; Type I error

c. Type I error; Type II error

nonparametric tests

chi-square goodness-of-fit test chi-square test for independence

A researcher recorded resilience among Marines who were either in the reserves, active duty, and officer corps following a single deployment to a foreign war zone. What type of parametric test is appropriate for analysis in this research situation? a. Two-way factorial design b. Within-subjects ANOVA c. Two-independent sample t-test d. Between-subjects ANOVA

d. Between-subjects ANOVA

Many non-parametric tests are called ________ because they make no assumptions regarding the shape of the distribution in the population. a. parametric tests b. skewed-distribution tests c. significance-free tests d. distribution-free tests

d. distribution-free tests

A decision made in null hypothesis significance testing: a. is always correct. b. is never correct. c. always reveals the truth. d. is always associated with some probability of error.

d. is always associated with some probability of error.

The probability or likelihood that an interval estimate will contain an unknown population parameter, is called: a. proportion of variance. b. confidence interval. c. level of significance. d. level of confidence.

d. level of confidence.

A criterion of judgment upon which a decision is made regarding the value stated in a null hypothesis, is called: a. absolute value. b. descriptive statistics. c. decisive criterion. d. level of significance.

d. level of significance.

The type of regression analysis used when two or more predictor variables are analyzed in the same model is called: a. Pearson correlation coefficient. b. linear regression. c. factorial analysis of variance. d. multiple regression.

d. multiple regression.

Inferential statistics includes a diverse set of tests of statistical significance more formally known as: a. non-hypothesis testing. b. random effect hypothesis testing. c. alternative hypothesis testing. d. null hypothesis significance testing.

d. null hypothesis significance testing.

The probability of obtaining a sample outcome, if the value stated in the null hypothesis is true, is called: a. effect size. b. significance. c. test statistic. d. p-value.

d. p-value. (computed from test statistic)

A measure of effect size in terms of the percent of variability in a dependent variable that can be explained or accounted for by the levels of a factor or treatment, is called: a. estimation. b. significance. c. correlation. d. proportion of variance.

d. proportion of variance.

Precision

determined by the range of the CI how close the estimate is

how do we increase statistical power in a study?

increase sample size

as the probability of one type of error decreases, the probability of the other type ( decreases | increases )

increases

Regression linear scale

interval or ratio

when to use logistic vs. linear

logistic - dependent variable is two categories linear - nominal or ordinal dependent variable

how to reduce error variance

matching (making group similar)

2 or more predictors - regression

multiple linear or logistic

to be more certain that an interval contains a population parameter, we typically give up _______________

precision

false

reject null hypothesis when null hypothesis is actually false

Type I Error

reject the null hypothesis when the null hypothesis is true: incorrectly decide one treatment or variable does have an influence when it does not

1 predictor - regression

simple linear or logisitic

lower effect size estimate

the difference between the value stated in the null hypothesis and the lower confidence limit

upper effect size estimate

the difference between the value stated in the null hypothesis and the upper confidence limit

Chi-Square Test for Independence

(Cramer's V) Same as R^2

Correlation and Regression

(R2) its value represents the proportion of variance in values of one factor that can be explained by changes in the values of a second factor

Suppose a population mean is equal to 1.5. If we select a sample at random from this population, we expect the sample mean would equal what value?

1.5

What type of estimate is identified by the interval or range of possible values within which an unknown population parameter is likely to be contained? a. Proportion b. Interval c. Significance d. Point

b. Interval

Which of the following are the two types of estimates using the process of estimation? a. Point estimate and proportion estimate b. Point estimate and interval estimate c. Significance estimate and effect size estimate d. Portion estimate and interval estimate

b. Point estimate and interval estimate

A researcher records the correlation between gender and response speed (in seconds) to a test stimulus (in seconds). Which correlation measure is most appropriate for this analysis? a. Spearman b. Point-biserial c. Phi d. Regression

b. Point-biserial

A researcher increases their level of confidence from 90% to 95% to estimate the population for a set of data. What will happen to the precision of their estimate for these data? a. The estimate will be more precise b. The estimate will be less precise c. The precision of their estimate will not change d. It depends on the size of the population

b. The estimate will be less precise

A developmental psychologist compares the time a small sample of infants spend near their mother in each of three novel contexts. What type of parametric test is appropriate for analysis in this research situation? a. One sample t-test b. Within-subjects ANOVA c. Related samples t-test d. Between-subjects ANOVA

b. Within-subjects ANOVA

We use null hypothesis significance testing to identify _______; we compute effect size to identify ________. a. the size of an effect; if an effect exists b. if an effect exists; the size of an effect c. significance; if an effect exists d. significance; significance

b. if an effect exists; the size of an effect

A significance test that is used to test hypotheses about data that can have any type of distribution and to analyze data on a nominal or ordinal scale of measurement, is called: a. parametric test. b. non-parametric test. c. effect size. d. confidence interval.

b. non-parametric test.

A researcher tests the hypothesis that music played at a fast speed and major scale will enhance arousal more than music at a slow speed and minor scale. The researcher finds that the data supports his hypothesis, therefore the decision for a null hypothesis significance test must have been: a. retain the null hypothesis. b. reject the null hypothesis. c. both retain and reject the null hypothesis. d. neither retain nor reject the null hypothesis.

b. reject the null hypothesis

The Mann-Whitney U test and the Wilcoxon Signed-Ranks T test are both non-parametric alternatives for: a. the chi-square test. b. the t-test. c. the ANOVA. d. the correlation coefficient.

b. the t-test.

Which of the following words best relates to inferential statistics? a. Describe b. Summarize c. Interpret d. Illustrate

c. Interpret

Which of the following is non-parametric alternative for an ANOVA? a. Chi-square test b. Mann-Whitney U test c. Kruskal-Wallis H test d. Wilcoxon Signed-Ranks T test

c. Kruskal-Wallis H test

What type of estimate uses a sample mean to estimate a population mean? a. Proportion b. Interval c. Point d. Significance

c. Point

Which correlation coefficient is used to analyze data on an interval or ratio scale?

Pearson

A chi-square test for independence is computed for a study with two categorical factors, each with three levels. What are the degrees of freedom smaller in this example? a. 2 b. 3 c. 6 d. 9

a. 2

Which type of hypothesis test can use Cohen's d as an estimate of effect size? a. One sample t-test b. One-way ANOVA c. Factorial ANOVA d. Pearson correlation coefficient

a. One sample t-test

A mean difference or discrepancy between what was observed in a sample and what was expected to be observed in the population as stated by a null hypothesis, is called: a. an effect . b. significance. c. power. d. proportion of variance.

a. an effect .

A statistical procedure in which a sample statistic is used to estimate the value of an unknown population parameter, is called: a. estimation. b. proportion of variance. c. significance testing. d. entanglement.

a. estimation.

A point estimate is generally the ____ of a confidence interval. a. midpoint b. lower boundary c. upper boundary d. level of confidence

a. midpoint

A point estimate is the ____ precise and the ____ certain estimate. a. most; least b. least; most c. largest; smallest d. smallest; largest

a. most; least

A significance test that is used to test hypotheses about parameters in a population in which the data in the population are normally distributed and measured on an interval or ratio scale of measurement, is called: a. parametric test. b. non-parametric test. c. effect size. d. confidence interval.

a. parametric test.

The probability of rejecting a false null hypothesis, is called: a. power. b. Type I error. c. Type II error. d. null finding.

a. power.

A researcher states that adult supervision during playtime significantly reduced aggressive behavior (p = .12). Is this conclusion appropriate at the .05 level of significance?

accept the null hypothesis (random chance) not significant

Type II Error

accept the null hypothesis when the null hypothesis is false: incorrectly decide a treatment or a variable has no influence when it does

A null finding means that: a. the decision was to reject the null hypothesis. b. a null hypothesis was discovered. c. the decision was to retain a null hypothesis. d. a null hypothesis has yet-to-be discovered.

c. the decision was to retain a null hypothesis.

A researcher computes a two-independent sample t-test. What type of research situation describes a situation in which this test is used to analyze the data? a. A graduate student selects a sample of participants to test if the time spend on task is greater than 30 minutes. b. A researcher matches right- and left-handed siblings to test if right-handed siblings express greater emotional intelligence than their right-handed counterparts. c. A professor tests whether students who repeat a course perform better on the first or second time they complete the course. d. A professor tests whether students who always sit in the front row of class score higher on class exams than students who always sit in the back row of class.

d. A professor tests whether students who always sit in the front row of class score higher on class exams than students who always sit in the back row of class.

A chi-square test for independence is computed for a study with two categorical factors, each with four levels. The researcher compute Cramer's V = .29. What is the size of the effect in this example? a. Trivial b. Small c. Medium d. Large

d. Large

A researcher reports a 95% CI -.02, .04. If the null hypothesis were that the mean in the population equals 0, then what is the effect size for this confidence interval? a. Effect size = .01 b. Effect size is between 0 and .04 points c. Effect size is between -.02 and .04 points d. No effect size can be reported for this CI

d. No effect size can be reported for this CI

All of the following statements about the precision and certainty of an estimate are true except: a. The precision of an estimate is determined by the range of the confidence interval. b. The larger the level of confidence, the more certain the estimate. c. To be more certain that an interval contains a population parameter, we typically give up precision. d. To be more certain that an interval contains a population parameter, we typically enhance precision.

d. To be more certain that an interval contains a population parameter, we typically enhance precision.

A researcher reports no effect in the population, when in truth there is an effect. What type of error has the researcher made? a. No error b. Type I error c. Type III error d. Type II error

d. Type II error

All of the following describes a situation in which a non-parametric test is used as an alternative to a parametric test except: a. a researcher records ranked data. b. a researcher recorded ordinal data. c. a researcher determines that the data are positively skewed. d. a researcher determines that the data are negatively skewed.

d. a researcher determines that the data are negatively skewed.

All of the following is an example of a parametric test except: a. analysis of variance. b. one sample t-test. c. Pearson correlation. d. chi-square test for independence.

d. chi-square test for independence.

A measure of proportion of variance used to describe effect size for data analyzed using a correlation coefficient or regression, is called: a. estimation. b. significance. c. correlation. d. coefficient of determination.

d. coefficient of determination.

All of the following statements for when to use a non-parametric test are true except: a. data in the population can have any type of distribution. b. data are measured on a nominal scale of measurement. c. data are measured on an ordinal scale of measurement. d. data are measured on a nominal scale of measurement.

d. data are measured on a nominal scale of measurement.

The larger the value of Cohen's d, the larger the: a. sample. b. estimate. c. significance. d. size of an effect.

d. size of an effect.

Certainty

determined by the level of confidence how confident you are in your estimate (inversely related with precision)

Regression logistic scale

nominal or ordinal

information in the CI can determine significance if:

null hypothesis falls outside of CI (if within CI, then it is not significant)

point-biserial

--- used when one variable is coded dichotomously and one is coded continuously (interval or ratio)

Pearson

--- used when both variables are measured on an interval or ratio scale

Spearman

--- used when both variables are measured on an ordinal scale

A researcher reduces their level of confidence from 99% to 90% to estimate the population for a set of data. What will happen to the precision of their estimate for these data? a. The estimate will be more precise b. The estimate will be less precise c. The precision of their estimate will not change d. It depends on the size of the population

a. The estimate will be more precise

A social psychologist asks men and women to read a vignette describing an immoral act committed for reason of preservation, protection, or self gain. Differences in rating of the person described in the vignette were compared across vignette type and gender. What type of parametric test is appropriate for analysis in this research situation? a. Two-way factorial design b. Multiple regression analysis c. Two-independent sample t-test d. Between-subjects ANOVA

a. Two-way factorial design

What is a key distinction between parametric tests and non-parametric tests in terms of scales of measurement? a. Parametric tests are used for interval and ratio data; whereas non-parametric tests are used for nominal and ordinal data. b. Parametric tests are used for ordinal and nominal data; whereas non-parametric tests are used for interval and ratio data. c. Parametric tests are used for ordinal or interval data; whereas non-parametric tests are used for nominal data only. d. There is no distinction; both types of tests are used to analyze data on any scale of measurement.

a. Parametric tests are used for interval and ratio data; whereas non-parametric tests are used for nominal and ordinal data.

A researcher test the hypothesis that students will have better recall of words printed in color vs. word printed in black on a white background. To test this hypothesis the researcher has students observe a screen with half the words in color and half the work in black. After 30 second, the screen is turned off and participants are asked to record all words they can recall. The mean number of colored vs. black print words correctly recalled was compared. What type of parametric test is appropriate for analysis in this research situation? a. Related samples t-test b. One sample t-test c. Two-independent sample t-test d. Chi-square test for independence

a. Related samples t-test

A researcher computes a one sample t-test. What type of research situation describes a situation in which this test is used to analyze the data? a. A study measuring difference in attitudes about morality among people who identify themselves as a democrat vs. republican. b. A study testing whether night shift workers sleep the recommended eight hours per 24-hour period. c. An experiment comparing brain activity levels in rats placed on a continuous vs. an intermittent reinforcement schedule. d. An Honors class is given an assessment at two times during the semester to test if the class is improving academic performance.

b. A study testing whether night shift workers sleep the recommended eight hours per 24-hour period.

A researcher evaluates the number of traffic accidents that occur daily at each of the four most-travelled roads in a local city to determine if one of the roads is more dangerous (i.e., has an unusually high proportion of traffic accidents). What type of analysis is appropriate for this research design? a. One-way analysis of variance b. Chi-square goodness-of-fit test c. Factorial analysis of variance d. Chi-square test for independence

b. Chi-square goodness-of-fit test

Which of the following is non-parametric alternative for the t-test? a. Chi-square test b. Mann-Whitney U test c. Kruskal-Wallis H test d. Mann-Whitney U test and Kruskal-Wallis H test

b. Mann-Whitney U test

A researcher reports a 95% CI 2.30, 2.50. If the null hypothesis were that the mean in the populaiton equals 2.00, then what would the decision have been for a significance test at a .05 level of significance? a. Retain the null because 2.00 is not contained in the confidence interval. b. Reject the null because 2.00 is not contained in the confidence interval. c. Retain the null because 2.00 is contained in the confidence interval. d. Reject the null because 2.00 is contained in the confidence interval.

b. Reject the null because 2.00 is not contained in the confidence interval.

What is the decision for a null hypothesis test when the likelihood of obtaining a sample outcome is less than 5% if the null hypothesis were true? a. Retain the null hypothesis b. Reject the null hypothesis c. Reject the alternative hypothesis d. Retain and reject the null hypothesis

b. Reject the null hypothesis

Suppose a researcher wants to make sure that the probability of committing a Type I error is less than 5%. How can the researcher control for this? a. Set the value for a Type II error at .05 b. Set the level of significance at .05 c. Only select 5% of the possible sample from a population d. Only select 95% of the possible sample from a population

b. Set the level of significance at .05

A researcher computes a within-subjects ANOVA. What type of research situation describes a situation in which this test is used to analyze the data? a. A social psychologist compares measures of social loafing among traditional and non-traditional college students. b. a college professor compares final exam grades among students in three separate sections of a research methods' class. c. a biopsychologist tests the time course for the release of a neurohormone before, during, and following a task thought to cause its release. d. a sports psychologist compares mental function scores in a sample of athletes from four different sports.

c. a biopsychologist tests the time course for the release of a neurohormone before, during, and following a task thought to cause its release.

The upper and lower boundaries of a confidence interval given within a specified level of confidence, is called: a. point estimate. b. level of significance. c. confidence limits. d. level of confidence.

c. confidence limits.

A statistical measure that allows researchers to describe how far scores shifted in a population, or the percent of variance in a dependent variable that can be explained by the levels of a factor, is called: a. estimation. b. significance. c. effect size. d. null hypothesis significance testing.

c. effect size.

In hypothesis testing a researcher can never: a. compute a test statistic before making a decision. b. make decisions about the null hypothesis. c. prove that their hypothesis is correct. d. know the likelihood of obtaining a sample mean if the null hypothesis were true.

c. prove that their hypothesis is correct.

The chi-square test is used to analyze what type of data? a. Continuous b. Interval c. Ratio d. Categorical

d. Categorical

A police academy records the number of men and women who pass or fail their physical training test, which a cadet must pass to become a police officer. To identify if there are gender differences in the pass-fail rate on the physical training test, what type of statistical test should be computed? a. One-way analysis of variance b. Chi-square goodness-of-fit test c. Factorial analysis of variance d. Chi-square test for independence

d. Chi-square test for independence

All of the following are examples of a measure of effect size except: a. Cohen's d. b. eta squared. c. coefficient of determination. d. Cronbach's alpha.

d. Cronbach's alpha.