Practice Questions
Researcher A reported r = -.86. Researcher B reported r = +.43. Which researcher reported the stronger correlation? A) Researcher A B) Researcher B
A
A researcher tests the extent to which the timing of a stimulus presentation, X, can be used to predict the frequency of a behavioral response, Y. Which factor is the predictor variable? A) the frequency of a behavioral response B) the timing of a stimulus presentation C) both factors are predictor variables in this example
B
A researcher tests the extent to which the wealth of a country can be used to predict the unemployment rate of a nation. Which factor is the criterion variable? A) the wealth of a country B) the unemployment rate of a nation C) both factors are criterion variables in this example
B
How many interactions are possible in the two-way between-subjects ANOVA? A) 0 B) 1 C) 2 D) 3
B
The correlation coefficient, r, can be converted to what values? A) coefficient of determination B) chi-square statistic C) t statistic D) all of the above
D
The farther the data points fall from the regression line, the larger the value of: A) predictive variation B) total variation C) residual variation D) regression variation
C
The one-way between-subjects ANOVA is used when different participants are assigned to __________ group(s). A) one B) two C) two or more D) zero
C
The test statistic compares the __________ between observed and expected frequencies. A) frequency B) outcome C) discrepancy D) effect size
C
The two-way ANOVA differs from the one-way ANOVA in that: A) the two-way ANOVA is used when we observe more than two groups B) the one-way ANOVA is used when we observe the levels of two factors C) the two-way ANOVA is used when we observe the levels of two factors D) the one-way ANOVA is used when we observe more than two groups
C
To interpret a significant chi-square goodness of fit test, we compared observed and expected frequencies: A) across the levels of the categorical variable B) between the levels of the categorical variable C) at each level of the categorical variable D) all of the above
C
To test for linear correlations, we assume that data points are __________ in general and at each point along the distribution of the other variance. A) positively correlated B) negatively correlated C) normally distributed D) positively skewed
C
Values of the __________ are known and can be used to predict values of the __________. A) predictor variable, predictor variable B) criterion variable, criterion variable C) predictor variable, criterion variable D) criterion variable, predictor variable
C
When pairs of scores for two factors move in the opposite directions, the slope of the regression is __________. A) nonlinear B) positive C) negative D) minimal
C
When the levels of one or more categorical variables are greater than two (for chi-square), we use _________ to estimate effect size. A) the proportion of variance B) the phi coefficient C) Cramer's V D) all of the above
C
When we measure data on a nominal or ordinal scale, we require hypothesis tests that use test statistics that do not analyze the __________. A) effect size B) significance C) variance D) meaning
C
Which of the following is a key assumption for the chi-square test? A) the data in the population are normally distributed B) the data are measured on an interval or ratio scale C) observed frequencies are recorded independently D) both a and c
C
Which of the following is a source of variation in the one-way between-subjects ANOVA? A) within-subjects variation B) between-subjects variation C) between-groups variation D) both b and c
C
A researcher asks if one predictor variable can significantly increase the prediction of Y beyond that already predicted by another predictor variable. Which value can allow the researcher to answer this question? A) the slope B) the proportion of variance C) the y-intercept D) the standardized beta coefficient
D
A researcher measures the following correlation between the amount of fat consumed in a diet and general health: r = -.62. Which of the following gives an appropriate description of the relationship between these two factors? A) as the amount of fat consumed in a diet increases, general health decreases B) about 38% of the variability in general health can be explained by the amount off at consumed in a diet C) increasing the amount of fat consumed in a diet causes a decline in general health D) both a and b
D
An estimate of the standard deviation or distance that a set of data points falls from the regression line is called: A) the criterion estimate B) the predictor estimate C) the standard error of the mean D) the standard error of estimate
D
Nonparametric tests are alternatives to parametric tests that are used to analyze data on which scales of measurement? A) nominal and ratio B) ordinal and interval C) interval and ratio D) nominal and ordinal
D
The __________ of the chi-square test statistic accounts for the relative size of a discrepancy between observed and expected frequencies. A) numerator B) frequency C) square root D) denominator
D
The source of variation that cannot be attributed to or caused by having different groups is called: A) within-groups variation B) error variation C) between-groups variation D) both a and b
D
The standard error of estimate is a measure of: A) the accuracy of predictions made using the equation of a regression line B) the square root of the mean square residual C) the distance that data points fall from the regression line D) all of the above
D
Unlike the t tests, the two-way ANOVA can be used when: A) the same participants are observed across groups B) different participants are observed across groups C) two groups are observed in the same study D) the levels of two factors are combined
D
What does the assumption of linearity refer to? A) that the variance of data points is minimal B) that all data points fall exactly on a straight line C) that the distribution of data points is normal D) that the best way to describe a pattern of data is using a straight line
D
When we arrange the data in an ANOVA test in a table, the number of cells represents the number of __________ in a study? A) participants B) factors C) researchers D) groups
D
Which of the following is a common reason to include a second factor in a research design? A) a hypothesis may require that we observe two factors B) to ensure that enough participants are included in a study C) to control for threats to validity D) both a and c
D
Which of the following is an assumption of the one-way between-subjects ANOVA? A) normality B) random sampling C) homogeneity of variance D) all of the above
D
Which of the following is not an assumption of the two-way between-subjects ANOVA? A) normality B) random sampling C) homogeneity of variance D) homogeneity of covariance
D
A researcher conducts a study in which a different group of participants is observed at each combination of levels for two factors. Which type of design is described for the two-way ANOVA? A) between-subjects design B) mixed design C) within-subjects design
A
A statistical procedure used to compute the slope and y-intercept of the best-fitting straight line to a set of data points is called: A) the method of least squares B) the method of most squares C) the method of common squares D) the method of data squares
A
Including multiple predictors in the regression equation can allow researchers to detect the extent to which two or more predictor variables __________. A) interact B) distribute C) consolidate D) equate
A
The __________ is a statistical procedure used to test hypotheses for one or more predictor variables to determine whether the regression equation for a sample of data points can be used to predict values of the criterion variable, given values of the predictor variable in the population. A) analysis of regression B) method of least squares C) coefficient of determination D) regression line
A
The ___________ of the correlation coefficient indicates the strength of a correlation. A) sign B) value C) strength D) linearity
A
The assumption that there is an equal variance of data points dispersed along the regression line is called: A) homoscedasticity B) correlation C) normality D) linearity
A
The count or frequency of participants recorded in each category or at each level of the categorical variable is called: A) frequency observed B) frequency expected C) both a and b
A
The size of an expected frequency should never be smaller than _____ in a given category. A) 5 B) 6 C) 9 D) 10
A
The standardized beta coefficient is used to analyze: A) the extent to which one predictor variable is a better predictor of variance in Y B) the method of least squares C) the formula for a regression line D) the residual variable left over by alpha
A
The test statistic equals ____ when the observed and expected frequencies are the same. A) 0 B) 1 C) a negative value D) a positive value
A
To accommodate more predictor variables in the equation of a regression line, we add the __________ and the __________ to the equation of the regression line for each additional variable. A) slope, predictor variable B) criterion variable, predictor variable C) coefficient of determination, sample size D) slope, coefficient of determination
A
Variation attributed to mean differences among participants scores within each group is called: A) within-groups variation B) within-subjects variation C) between-groups variation D) both a and b
A
What is the limitation in which the range of data for one or both factors in a sample is smaller than the range of data in the larger population? A) restriction of range B) outliers C) correlation D) causality
A
When we arrange the data in an ANOVA test in a table, the combination of one level from each factor is called a: A) cell B) design C) factor D) combo
A
Which measure of proportion of variance tends to overestimate the size of an effect in a population? A) eta-squared B) omega-squared
A
___________ are hypothesis tests that are 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. A) parametric tests B) nonparametric tests C) both a and b
A
___________ is a statistical procedure used to determine the equation of the regression line to a set of data points and to determine the extent to which the regression equation can be used to predict values of one factor, given known values of a second factor in a population. A) linear regression B) evaluation C) predictor testing D) criterion testing
A
A significant correlation shows that two factors are __________, not that one factor __________ changes in a second factor. A) causal, is related to B) related, causes
B
A source of variation associated with the variance of group means across the combination of levels of two factors is called a(n): A) main effect B) interaction C) cell mean D) variable
B
A statistical procedure used to test hypotheses for one factor with two or more levels concerning the variance among group means, where different participants are observed at each level of a factor, is called the: A) two-independent-sample t test B) one-way between-subjects ANOVA C) two-way between-subjects ANOVA D) one-sample t test
B
Homogeneity of variance refers to the assumption that: A) data in the population or populations being sampled from are normally distributed B) the variance of scores in each population is equal C) the probabilities of each measured outcome in a study are independent D) the data were selected using a random sampling procedure
B
Researcher A measures intelligence scores among participants of different handedness (left-handed, right-handed). Researcher B measures characteristics of handwriting among participants asked to write with both their left and right hands. Which researcher included a within-subjects factor in the research design? A) Researcher A B) Researcher B C) none, because both factors were between-subjects factors D) both, because both factors were within-subjects factors
B
The null hypothesis for a chi-square test for independence is that: A) two categorical variables are dependent or related B) two categorical variables are independent or unrelated
B
The standardized beta coefficient equals the value of the unstandardized beta coefficient when we analyze: A) one criterion variable B) one predictor variable C) more than one predictor variable D) any number of criterion and predictor variables
B
Which of the following is NOT an assumption to test for the significance of a linear correlation? A) homoscedasticity B) independence C) normality D) linearity
B
Which post hoc test is associated with the greatest power to detect an effect? A) Tukey's HSD test B) Fisher's LSD test C) one-way between-subjects test
B
__________ are hypothesis tests that are used 1) to test hypotheses that do not make inferences about parameters in a population, 2) to test hypotheses about data that can have any type of distribution, and 3) to analyze data on a nominal or ordinal scale of measurement. A) parametric tests B) nonparametric tests C) both a and b
B
A main effect is a source of variation associated with mean differences: A) in the cell means given in a table summary B) across the combination of levels of two factors C) across the levels of a single factor D) across the combination of levels of two or more factors
C
A measure of the proportion of variance in one factor (Y) that can be explained by known values of a second factor (X) is called the: A) covariance B) correlation coefficient C) coefficient of determination D) regression line
C
A researcher conducts a study in which the same group of participants is observed at each combination of levels for two factors. Which type of design is described for the two-way ANOVA? A) between-subjects design B) mixed design C) within-subjects design
C
A statistical method that includes two or more predictor variables in the equation of a regression line to predict changes in a criterion variable is called: A) standard regression B) estimate regression C) multiple regression D) two-way regression
C
A statistical procedure used to describe the strength and direction of the linear relationship between two factors is called a: A) parameter B) factor C) correlation D) confound
C
An analysis of regression measures only the variance in ____ because it is the value we want to predict. A) X B) the predictor variable C) Y D) both a and b
C
Hypothesis tests used to analyze a significant interaction by comparing the mean differences of one factor at each level of a second factor are called: A) effect size tests B) two-way ANOVA tests C) simple main effect tests
C
In a two-way between-subjects ANOVA, which effect should be analyzed first when it is significant? A) the main effect of Factor A B) he main effect of Factor B C) the interaction
C
Outliers can obscure the relationship between two factors by altering the: A) extent to which two correlations are related to a third factor B) the extent to which changes in one factor cause changes in a second factor C) direction and strength of an observed correlation coefficient D) none of the above
C
Simple main effect tests are necessary to analyze: A) a significant main effect B) any significant effect C) a significant interaction D) the results of a one-way ANOVA
C