## Exam (elaborations)

# [Solved] University of Central Florida - EXAM 5

University of Central Florida - EXAM 5 Score for this quiz: 106 out of 120 Submitted Nov 12 at 8:31pm This attempt took 55 minutes. Question 1 Correct! 2 / 2 pts Skip to question text. In a reanalysis of published studies, Twenge and Im (2007) found that for the time period 1958–2001, the need for social approval of people in the United States was negatively correlated with the U.S. violent crime rate during the same period (the correlation coefficient was –0.31). This correlation means that: as the need for social approval went up, the number of violent crimes decreased. Question 2 Correct! 2 / 2 pts What kind of correlation would you expect to find between levels of family income and household spending on consumer goods?<br> What kind of correlation would you expect to find between levels of family income and household spending on consumer goods? positive negative zero perfect positive Question 3 Correct! 2 / 2 pts The numerator (top half) of the Pearson correlation coefficient formula includes:<br> The numerator (top half) of the Pearson correlation coefficient formula includes: the square root of the product of the two sums of squares. the difference between the two sample means. the sum of the product of the deviations for each variable. . Question 4 Correct! 2 / 2 pts What kind of correlation would you expect to find between the age of a car (nonclassic) and its value?<br> What kind of correlation would you expect to find between the age of a car (nonclassic) and its value? zero perfect positive negative positive Question 5 Correct! 2 / 2 pts A negative correlation between a hockey player's age and the number of minutes he spends in the penalty box indicates that:<br> A negative correlation between a hockey player's age and the number of minutes he spends in the penalty box indicates that: older players make fewer penalties because they have reduced testosterone levels. an older player's greater experience has taught him how to avoid making penalties. the older a player is, the less time he spends in the penalty box. spending more time on the ice leads hockey players to become skilled at avoiding the referees. Question 6 Correct! 2 / 2 pts A positive correlation between head size and foot size indicates that:<br> A positive correlation between head size and foot size indicates that: people with larger feet tend to have smaller heads. having a large head causes a person to have large feet. having large feet causes a person to have a large head. people with larger feet also tend to have larger heads. Question 7 Correct! 2 / 2 pts To predict a single dependent variable from more than one independent variable, which statistical technique would we use?<br> To predict a single dependent variable from more than one independent variable, which statistical technique would we use? simple linear regression correlation structural equation modeling multiple regression Question 8 Correct! 2 / 2 pts Skip to question text. In a reanalysis of published studies, Twenge and Im (2007) found that for the time period of 1958 to 2001, the need for social approval of people in the United States was positively correlated with changes in the Dow Jones Industrial Average during that same period (the correlation coefficient was 0.10). This means that: the need for social approval prevented people from investing money in the stock market. as the need for social approval went up, the Dow Jones decreased. as the need for social approval went up, the Dow Jones also increased. the need for social approval caused people to invest more money in the stock market. Question 9 Correct! 2 / 2 pts As the standard error of estimate becomes larger, predictions become:<br> As the standard error of estimate becomes larger, predictions become: more accurate. larger. less accurate. smaller. Question 10 Incorrect 0 / 2 pts A simple way to calculate proportionate reduction in error is by:<br> A simple way to calculate proportionate reduction in error is by: taking the square root of the correlation coefficient. squaring the correlation coefficient. adding the slope and y intercept. Question 11 Correct! 2 / 2 pts Skip to question text. Researchers who study the process of reading in children have discovered that better readers make smoother eye movements across the page (i.e., there is a positive correlation between reading skill and the smoothness of the eye movements). Which of the following statements a possible cause of the correlation between smooth eye movements and reading ability? Having good reading skill allows a child to make smooth eye movements. The ability to make smooth eye movements improves reading ability. All of these options are possible causes of the correlation. Some third factor might cause both smooth eye movements and improved reading ability. Question 12 Incorrect 0 / 2 pts Regression is to ________ as correlation is to ________.<br> Regression is to ________ as correlation is to ________. relation; prediction prediction; relation association; causation Question 13 Correct! 2 / 2 pts Skip to question text. In a reanalysis of published studies, Twenge and Im (2007) found that for the time period 1958–2001, the need for social approval of people in the United States was negatively correlated with the U.S. divorce rate during the same period (the correlation coefficient was –0.38). This correlation means that: as the need for social approval increased, divorce rates increased. the need for social approval spurred people to divorce. the need for social approval prevented people from seeking divorce. as the need for social approval increased, divorce rates decreased. Question 14 Correct! 2 / 2 pts According to guidelines published by Cohen (1988), a correlation value of ________ is considered small, ________ is medium, and _______ is strong.<br> According to guidelines published by Cohen (1988), a correlation value of ________ is considered small, ________ is medium, and _______ is strong. 1.00; 2.00; 3.00 0.25; 0.50; 0.75 0.40; 0.60; 0.80 0.10; 0.30; 0.50 Question 15 Incorrect 0 / 2 pts Which of the following numbers would represent a perfect correlation?<br> Which of the following numbers would represent a perfect correlation? –1.00 –1.00 or 1.00 0 1.00 Question 16 Correct! 2 / 2 pts Imagine that you've just read the results of a study that finds a positive correlation between gum chewing and life expectancy. Which of the following statements would be a statistically appropriate response to the results of the study?<br> Imagine that you've just read the results of a study that finds a positive correlation between gum chewing and life expectancy. Which of the following statements would be a statistically appropriate response to the results of the study? You purchase a lifetime supply of gum because chewing gum is good for your health. You become curious about what third variables might cause both increases in gum chewing and increases in life expectancy. You bemoan the possibility of living so long that you will have to chew lots of gum. You tell all your friends and family members to chew gum because it is good for their health. Question 17 Correct! 2 / 2 pts The denominator (bottom half) of the Pearson's correlation coefficient includes:<br> The denominator (bottom half) of the Pearson's correlation coefficient includes: the difference between the sample means. S(X – Mx)(Y – My). the sum of the product of the deviations for each variable. the square root of the product of the two sum of squares. Question 18 Correct! 2 / 2 pts Which of the following numbers would indicate the strongest relationship between two variables?<br> Which of the following numbers would indicate the strongest relationship between two variables? –0.25 0.59 0.65 –0.72 Question 19 Correct! 2 / 2 pts The tendency of scores that are particularly high or low to drift toward the mean over time is called:<br> The tendency of scores that are particularly high or low to drift toward the mean over time is called: simple linear regression. regression to the mean. standard error of the estimate. standard error of the mean. Question 20 Correct! 2 / 2 pts Simple linear regression allows us to:<br> Simple linear regression allows us to: predict an individual's score on a dependent variable from her score on multiple independent variables. infer the direction of causal relations. determine the relation among four or more variables. predict an individual's score on the dependent variable from her score on the independent variable. Question 21 Correct! 2 / 2 pts “The incidence of depression among college students is negatively correlated with the number of sunny days each year in the locale where they attend college.” This statement means that:<br> “The incidence of depression among college students is negatively correlated with the number of sunny days each year in the locale where they attend college.” This statement means that: a student attending college in a locale with very few sunny days will become depressed. the chances of a college student being depressed tend to increase with fewer sunny days. the chances of a college student being depressed tend to increase as the number of sunny days increases. if a depressed student were to move to a locale with more sunny days, her depression would subside. Question 22 Correct! 2 / 2 pts What kind of correlation would you expect to find between snowstorms and attendance at college classes?<br> What kind of correlation would you expect to find between snowstorms and attendance at college classes? perfect negative negative zero positive Question 23 Correct! 2 / 2 pts What is the null hypothesis when testing for significance using the Pearson correlation coefficient?<br> What is the null hypothesis when testing for significance using the Pearson correlation coefficient? r = 0 r = 1 m1 = m2 r 0 Question 24 Correct! 2 / 2 pts If the correlation between the number of beers consumed over a semester and the GPA for the semester is –0.56, what would we predict the z score to be for a person who had a z score of 0.80 for the number of beers consumed?<br> If the correlation between the number of beers consumed over a semester and the GPA for the semester is –0.56, what would we predict the z score to be for a person who had a z score of 0.80 for the number of beers consumed? –0.45 –1.43 0.45 1.43 Question 25 Correct! 2 / 2 pts Skip to question text. Data from the 1993 World Almanac and Book of Facts were used to predict the life expectancy for men in a country from the life expectancy of women in the country. The resulting regression equation was Ŷ = 9.32 0.79(X). This regression equation implies that: when a woman's life expectancy increases by 1 year, a man's life expectancy increases by 0.79 of a year. women live 0.79 times as long as men do. the average life expectancy for women in some countries is 9.32. the average life expectancy for men in some countries is 9.32. Question 26 Correct! 2 / 2 pts Skip to question text. 1995 data from over 1,000 colleges published in U.S. News & World Report were used to predict the percent of alumni who donate to a college from the average SAT score of students attending the college. The resulting regression equation was Ŷ = –29.29 0.05(X). Using the regression equation, what would you predict to be the percent of alumni who will donate to a college whose students' average SAT score is 1020? 62.6% 21.71% 0.6% 80.29% Question 27 Correct! 2 / 2 pts If all the points on a scatterplot fall on a single line:<br> If all the points on a scatterplot fall on a single line: there is a positive correlation between the two variables. the variables are causally related. the relation between the variables is perfect. there is no relation between the variables. Question 28 Correct! 2 / 2 pts The first step involved in calculating the Pearson correlation coefficient is to: <br> The first step involved in calculating the Pearson correlation coefficient is to: multiply each raw score in one variable by the corresponding raw score in the second variable. calculate the deviation of each score from its mean. calculate the standard deviation for each variable. square all the scores. Question 29 Correct! 2 / 2 pts Every year it seems as though last season's baseball rookie of the year fails to live up to expectations for his sophomore season. What might explain this phenomenon?<br> Every year it seems as though last season's baseball rookie of the year fails to live up to expectations for his sophomore season. What might explain this phenomenon? regression to the mean proportionate reduction in error standard error of the estimation overestimation of effect size Question 30 Correct! 2 / 2 pts If two variables, independently, can help us predict the outcome of a third variable, we say that they are:<br> If two variables, independently, can help us predict the outcome of a third variable, we say that they are: standardized. proportionate. orthogonal. autonomous. Question 31 Correct! 2 / 2 pts If the correlation between the number of ounces of candy a child consumes weekly and the number of cavities the child has at the age of 13 is 0.78, what would we predict for a child who had a z score of –1.2 on the candy-consumed variable?<br> If the correlation between the number of ounces of candy a child consumes weekly and the number of cavities the child has at the age of 13 is 0.78, what would we predict for a child who had a z score of –1.2 on the candy-consumed variable? The z score on the variable number of cavities would be –1.54. The z score on the variable number of cavities would be –0.94. The z score on the variable number of cavities would be 1.54. The z score on the variable number of cavities would be 0.94. Question 32 Correct! 2 / 2 pts Assume that the correlation coefficient between class attendance and number of problems missed on an exam is (–0.77). Which statement regarding this finding is correct?<br> Assume that the correlation coefficient between class attendance and number of problems missed on an exam is (–0.77). Which statement regarding this finding is correct? The correlation provides definitive information pertaining to causation. There is definitely no causal relationship between the two variables. If you attend class regularly, you are more likely to do well on the exam than one who does not attend class regularly. If you start attending class more regularly, the number of problems you miss on the next exam is certain to be reduced. Question 33 Correct! 2 / 2 pts Y is the symbol for a(n) ________ and Ŷ is the symbol for a(n) ________.<br> Y is the symbol for a(n) ________ and Ŷ is the symbol for a(n) ________. observed score; predicted score predicted score; observed score score on the independent variable; score on the dependent variable score on the dependent variable; score on the independent variable Question 34 Correct! 2 / 2 pts A high standard error of the estimate indicates that the:<br> A high standard error of the estimate indicates that the: sample mean is not a very good representation of the population mean. observedYs will vary greatly from the predicted Ys. observedYs will cluster closely around the regression line. mean is not a very good representation of the sample data. Question 35 Incorrect 0 / 2 pts The predicted z score for the dependent variable will always be ________ the individual's z score for the independent variable.<br> The predicted z score for the dependent variable will always be ________ the individual's z score for the independent variable. less than more than two times Question 36 Incorrect 0 / 2 pts Skip to question text. In a study designed to predict blood cholesterol levels from amount of daily saturated fat in grams (X1) and number of hours of daily exercise (X2), we determine that the slope of X1 is 5, the slope of X2 is –4, and the y intercept is 130. If someone reports that they typically eat 10 grams of saturated fat daily and exercise 1 hour daily, what would you predict for the person's cholesterol level? 184 150 176 Question 37 Correct! 2 / 2 pts Which of the following statistics quantifies the improvement in ability to predict a person's score when using the regression line rather than the mean?<br> Which of the following statistics quantifies the improvement in ability to predict a person's score when using the regression line rather than the mean? slope standard error of the estimation standard deviation proportionate reduction in error Question 38 Correct! 2 / 2 pts Why do correlation coefficients greater than 0.50 rarely occur in the social sciences?<br> Why do correlation coefficients greater than 0.50 rarely occur in the social sciences? The highest value a correlation coefficient can take on is 0.60. Human behavior is the product of many interacting variables; any single variable will be limited in its association with a behavior. Social scientists have not yet discovered the variables that are the best predictors of human behavior. Social scientists fail to construct experiments carefully enough to detect larger correlations. Question 39 Correct! 2 / 2 pts When conducting a hypothesis test for the Pearson correlation coefficient, we are testing the null hypothesis that our correlation value is significantly different from:<br> When conducting a hypothesis test for the Pearson correlation coefficient, we are testing the null hypothesis that our correlation value is significantly different from: 1.00. 0. either 1.00 or –1.00. –1.00. Question 40 Correct! 2 / 2 pts A Pearson correlation coefficient is calculated for 48 individuals. What value of df should be used to determine statistical significance in hypothesis testing?<br> A Pearson correlation coefficient is calculated for 48 individuals. What value of df should be used to determine statistical significance in hypothesis testing? 47 46 48 45 Question 41 Correct! 2 / 2 pts In the equation for a regression line, the intercept is the:<br> In the equation for a regression line, the intercept is the: predicted value for Y when X is equal to 0. value for X when Y is equal to 0. amount that Y is predicted to increase for a 1-unit increase in X. z score of the amount that Y is predicted to increase as X increases. Question 42 Correct! 2 / 2 pts Which of the following values of the correlation coefficient indicates the weakest relationship between two variables?<br> Which of the following values of the correlation coefficient indicates the weakest relationship between two variables? –0.87 0.42 –0.30 0.03 Question 43 Correct! 2 / 2 pts Skip to question text. Based on research with her patients, Dr. Sabine knows that the correlation coefficient between scores on an anxiety scale and comfort at a social gathering is –0.35. According to guidelines established by Cohen, how could we characterize the strength of this relationship? very large small medium large Question 44 Incorrect 0 / 2 pts If the standard error of the estimate is zero, the relation between two variables is:<br> If the standard error of the estimate is zero, the relation between two variables is: perfect. curvilinear. unknown. Question 45 Correct! 2 / 2 pts Skip to question text. A researcher wants to be able to predict first-semester grade point average with as much accuracy as possible, so she would like to use both high grade point average and SAT score as predictor variables. Which of the following techniques would be most appropriate to make this prediction? proportionate reduction in error simple linear regression standardized regression coefficient multiple regression Question 46 Correct! 2 / 2 pts The proportionate reduction in error is a measure of the:<br> The proportionate reduction in error is a measure of the: variability of the dependent measure. amount of variance in the dependent variable explained by the independent variable. slope of a regression line. correlation between two variables. Question 47 Correct! 2 / 2 pts Researchers who study the process of reading in children have discovered that better readers make smoother eye movements across the page. If we drew a scatterplot of the data, the points on the graph would likely run from ________ to ________.<br> Researchers who study the process of reading in children have discovered that better readers make smoother eye movements across the page. If we drew a scatterplot of the data, the points on the graph would likely run from ________ to ________. upper left; lower right upper left; upper right lower left; lower right lower left; upper right Question 48 Correct! 2 / 2 pts Skip to question text. Data from the 1993 World Almanac and Book of Facts were used to predict the life expectancy for men in a country from the life expectancy of women in the country. The resulting regression equation was Ŷ = 9.32 0.79(X). Using the regression equation, what would you predict to be the life expectancy of men in a country in which the life expectancy for women is 65 years? 74.32 years 69.68 years 55.68 years 60.67 years Question 49 Correct! 2 / 2 pts What kind of correlation would you expect to find between the results of two dice thrown simultaneously?<br> What kind of correlation would you expect to find between the results of two dice thrown simultaneously? perfect positive zero positive negative Question 50 Correct! 2 / 2 pts The standard error of the estimate indicates:<br> The standard error of the estimate indicates: the typical distance between the regression line and each of the observed data points. how much error there is in any single prediction we make from a given regression equation. how far, on average, the regression line is from the mean. how far two regression lines are from each other. Question 51 Correct! 2 / 2 pts The standard error of estimate could be thought of as the:<br> The standard error of estimate could be thought of as the: standard deviation of the dependent variable. amount of error made in random selection. standard deviation of the independent variable. standard deviation of the data points around the regression line. Question 52 Correct! 2 / 2 pts The numerical value for a correlation ranges between ________ and ________.<br> The numerical value for a correlation ranges between ________ and ________. –1.00; 0 –1.00; 1.00 negative infinity; positive infinity 0; 1.00 Question 53 Correct! 2 / 2 pts Suppose a researcher discovers that following a Mediterranean diet is negatively correlated with risk of developing cancer. Which of the statements logically follows from this information?<br> Suppose a researcher discovers that following a Mediterranean diet is negatively correlated with risk of developing cancer. Which of the statements logically follows from this information? People who eat a Mediterranean diet are less likely to have cancer. Eating a Mediterranean diet increases the risk of developing cancer. Eating a Mediterranean diet reduces the risk of developing cancer. Question 54 Correct! 2 / 2 pts When conducting a hypothesis test for the Pearson correlation coefficient, degrees of freedom is calculated by:<br> When conducting a hypothesis test for the Pearson correlation coefficient, degrees of freedom is calculated by: (N1 – 1)(N2 – 1). N – 1. N – 2. S(X – Mx)2. Question 55 Correct! 2 / 2 pts According to guidelines published by Cohen (1988), a correlation value of –0.55 would be considered:<br> According to guidelines published by Cohen (1988), a correlation value of –0.55 would be considered: medium. small. large. very large. Question 56 Incorrect 0 / 2 pts The denominator of the Pearson correlation equation corrects for ________ and ________ issues present in the numerator.<br> The denominator of the Pearson correlation equation corrects for ________ and ________ issues present in the numerator. negative values; nonlinear data sample size; nonnormality sample size; variability Question 57 Correct! 2 / 2 pts Before calculating the correlation coefficient, it is advisable to create a ________ as a way of displaying the association between the two variables.<br> Before calculating the correlation coefficient, it is advisable to create a ________ as a way of displaying the association between the two variables. histogram line graph polygon scatterplot Question 58 Correct! 2 / 2 pts If a negative relation exists between two variables, then low scores on one variable will be associated with ________ scores on the other variable.<br> If a negative relation exists between two variables, then low scores on one variable will be associated with ________ scores on the other variable. both high and low low high neither high nor low Question 59 Correct! 2 / 2 pts The regression line is the line that:<br> The regression line is the line that: is the mean of the dependent variable. minimizes error in predicting scores on the dependent variable. minimizes the correlation coefficient. minimizes error in predicting scores on the independent variable. Question 60 Correct! 2 / 2 pts Skip to question text. 1995 data from over 1,000 colleges published in U.S. News & World Report were used to predict the percent of alumni who donate to a college from the average SAT score of students attending the college. The resulting regression equation was Ŷ = –29.29 0.05(X). This regression indicates that: for every 1-dollar increase in donations, the college can expect a half-point increase in SAT scores. most colleges do not have very high alumni donation rates. for every 1-point increase in SAT scores, a college can expect 0.05% fewer alumni to donate. for every 1-point increase in SAT scores, a college can expect 0.05% more of its alumni to donate. Quiz Score: 106 out of 120