Psychological Statistics Final Exam Questions And Answers Guaranteed Pass.

George calculates the F-ratio for a one way ANOVA comparing the means of 3 groups: Group A (M=4.12), Group B (M=7.37) and Group C (M=8.92). If he makes a decision to reject the null hypothesis, what is the most specific and appropriate conclusion that he can make? - correct answers The groups are not all equal to each other When researchers have a plan regarding the comparisons between groups needed to test their research hypotheses, these comparisons are known as ________________. - correct answers Planned comparisons The theoretical distribution of F-ratios is ________________. - correct answers Asymmetric The F-ratio is calculated by _________________. - correct answers Dividing between-group variance by within-group variance Within-group variability may also be thought of as ______________. - correct answers Error The degrees of freedom between groups indicates _______________. - correct answers The number of levels of the independent variable A researcher hypothesizes that freshmen spend more time studying than sophomores, who spend more time studying than juniors, and so on. In conducting a one-way ANOVA with this data, how can the null hypothesis be stated? - correct answersH0: all mu's are equal The probability of making at least one type 1 error across a set of comparison is referred to as _____________. - correct answersFamilywise error The Tukey Test limits familywise error by ______________. - correct answersIncreasing the critical value of the statistic needed to reject the null hypothesis for each comparison The main purpose of conducting analytical comparisons is to _______________. - correct answersCompare groups with each other What is a disadvantage of using factorial designs versus single-factor designs? - correct answersTesting and interpreting effects in a factorial research design is more complicated than single-factor design __________ occurs when the effect of one independent variable on the dependent variable changes at the different levels of another independent variable - correct answersAn interaction effect The total number of combinations in a factorial research design is calculated by ______________. - correct answersMultiplying the number of levels of the independent variables A ______________ is a research design consisting of one independent variable - correct answersSingle-factor research design A ___________ is a research design consisting of all possible combinations of two or more independent variables - correct answersFactorial research design The main effects would be equivalent to what type of information? - correct answersInformation that would be obtained by conducting separate single-factor research designs for each of the independent variables When stating the null and alternative hypotheses, the two main effects are treated as _____________. - correct answersSingle-factor designs Which of the following is one aspect of the relationship between main effects and interaction effects? - correct answersThe presence of=r absence of main effects provides no indication of whether an interaction effect is present or absent A(n) ____________ is the effect of one independent variable on the dependent variable that changes at the different levels of another independent variable - correct answersInteraction effect A ___________ is the effect of an independent variable on the dependent variable within a factorial research design - correct answersMain effect A researcher hypothesizes a relationship between anxiety levels and one's level of fear. If she reports "F(1,30)=5.25, p.05," her research hypothesis has _____________ because the null hypothesis was ______________. - correct answersBeen supported; rejected The difference between correlational statistics and correlational research is that ____________. - correct answersCorrelational statistics refers to the way that data is analyzed What reason would you create a scatter plot between 2 variables? - correct answersTo get a sense of the strength of the relationship, to see if the relationship is linear, or to see if the relationship is positive or negative What reason would you most likely calculate a correlation coefficient? - correct answersIndependent variable = age; dependent variable = reaction time in milliseconds You believe students are less attentive in class when they either get too little or too much sleep as opposed to their average amount of sleep. This is an example of a ___________ relationship. - correct answersNonlinear You calculate the correlation coefficient between 2 variables when the __________ is ____________. - correct answersIndependent variable; continuous A recent study found that the older the college student, the fewer the number of pages assigned readings the student reads. The relationship between age of student and amount of reading may be described as _____________. - correct answersNegative A researcher collects data from 18 people and calculates a Pearson correlation of r = -.42. Assuming alpha = .05 (two-tailed), the researcher would make the decision to ______________. - correct answersNot reject the null hypothesis (p.05) The Spearman rank-order correlation is used with variables measured at the ___________ level of measurement. - correct answersOrdinal Two restaurant reviewers wish to see if they have similar opinions regarding restaurants. They independently rank-order 8 restaurants from 1 (best) to 8 (worst). Calculating a Spearman rank-order correlation, they would find the following result: r(6) = .47, p.05. Based on the result of this analysis, what conclusion would be drawn? - correct answersThere is no relationship between the 2 reviewers' opinions of restaurants What is a statement that best illustrates the concept of covariance? - correct answers"Students who score below the class mean on the midterm also score below the mean on the final exam" In calculating the Pearson correlation (r), the null hypothesis implies _______________. - correct answersThere is no relationship The sign (+/-) of a Pearson correlation coefficient (r) assesses the ____________ of the relationship between 2 variables. - correct answersDirection Including multiple predictors in one analysis ______________. - correct answersShould increase the amount of explained variance in the criterion If there is zero correlation between 2 variables, the linear regression equation based on this correlation is a ____________ line. - correct answersHorizontal The value for the slope of the regression equation is _______________. - correct answersEither positive or negative A researcher studying the relationship between drivers' average speed (MPH) on the highway and number of moving violations they receive develops the following regression equation: Y' = 1.85 + .05x. In the example, Y' refers to _____________. - correct answersA drivers' number of moving violations The main purpose of regression is to _____________. - correct answersPredict scores on a variable _____________ is the use of a relationship between 2 or more correlated variables to predict values of one variable from values of other variables - correct answersRegression The linear regression equation represents ______________. - correct answersThe "best fit" relationship between 2 variables What is a disadvantage of multiple correlation compared with Pearson correlation? - correct answersInterpreting a multiple correlation is more complicated than interpreting a Pearson correlation The first step in calculating the linear regression equation is to ___________. - correct answersCalculate the slope For data that yielded an intercept of 3.66 and a slope of .15, what would be the appropriate linear regression equation? - correct answersY' = 3.66 + .15x When a continuous variable is normally distributed, a nonparametric test has ____________ statistical power than its parametric counterpart. - correct answersLess Nonparametric statistical tests such as __________ do not involve the estimation of population parameters. - correct answersChi-square statistics One assumption of the chi-square statistic is that each observation in a set of data is ______________. - correct answersIndependent of all observations The results of the chi-square test of independence found that fear of crime depended on one's perception of whether their neighborhood was a high crime area or not. If the null hypothesis is rejected, which is the most appropriate conclusion that can be made? - correct answersOne's fear of crime is related to whether or not they believe their neighborhood to be a high crime area For X^2 = 4.05 with the number of groups = 3, the researcher would _____________. - correct answersNot reject the null hypothesis (p.05) When data are normally distributed, using a nonparametric test (rather than its parametric counterpart) is more likely to lead to _____________. - correct answersType II error Which statistical procedure should be conducted if any of the expected frequencies (fe) are less than 5? - correct answersFisher's exact test When reporting the results of a chi-square test of independence, on would include __________. - correct answersThe X^2, the sample size, and the measure of effect size Which of the following is an assumption about nonparametric tests? - correct answersThey do not require variables to be normally distributed If most of the expected frequencies (fe) are not greater than 5, the chi-square has the limited ability to resemble or approximate ____________. - correct answersThe population from which the sample was drawn Frequency of a group in the sample data - correct answersObserved frequency (fo) Frequency of a group expected to occur in a sample of data under the assumption the null hypothesis is true - correct answersExpected frequency Statistic that tests the difference between the distribution of observed frequencies and expected frequencies - correct answersChi-square statistic Statistic that tests the difference between the distribution of observed frequencies and expected frequencies for a single variable - correct answersChi-square goodness-of-fit test Measure of effect size for the chi-square statistic - correct answersCramer's phi Assumption that each observation in a set of data is independent of all other observations - correct answersAssumption of independence of observations Chi-square statistic used if any of the expected frequencies in a sample of data are less than 5 - correct answersFisher's exact test Chi-square statistic used when any of the expected frequencies in a sample of data are between 5 and 10 - correct answersYate's correction for continuity Table in which the rows and columns represent the values of categorical variables and the cells contain observed frequencies for combinations of the variables - correct answersContingency table Statistic that tests the difference between the distribution the distribution of observed frequencies and expected frequencies for 2 categorical variables - correct answersChi-square test for independence Statistical tests based on assumption that data from a sample are being used to estimate population parameters and that the distribution of scores for a variable is normally distributed in the larger population - correct answersParametric statistical test Statistical tests that do not involve the estimation of population parameters or the assumption that scores for a variable are normally distributed in the larger population - correct answersNonparametric statistical test Research design consisting of one independent variable - correct answersSingle-factor research design Research design consisting of all possible combinations of 2 or more independent variables - correct answersFactorial research design Graphical display of paired scores on 2 variables measured at the interval or ratio level of measurement - correct answersScatter plot Mutual or reciprocal relationship between 2 variables such that systematic changes in the values of one variable are accompanied by systematic changes in the values of another variable - correct answers Correlation Relationship between 2 variables approximately represented by a straight line