Psych 311 Exam 4 Questions With 100% Pass

Psych 311 Exam 4 Questions With 100% Pass The correlation coefficient measures the extent to which changes in one factor are _______ in a second factor. A) related to changes B) causing changes C) causing variability D) all of the above - Answer- related to changes A Pearson r statistic would be the proper statistic to use to test the relationship between A) height and weight B) height and birth order (1st born, 2nd born, etc.) C) retirement status (yes or no) and blood pressure D) retirement status (yes or no) and death penalty view (pro vs. con) - Answer- height and weight The normality assumption states that the population of X and Y scores form a bivariate ("two variable") normal distribution, such that A) the population of X and Y scores are normally distributed B) for each X score, the distribution of Y scores is normally distributed C) for each Y score, the distribution of X scores is normally distributed D) all of the above - Answer- all of the above What is a key distinction between parametric tests and nonparametric tests in terms of scales of measurement? A) Parametric tests are used for interval and ratio data, whereas nonparametric tests are used for nominal and ordinal data. B) Parametric tests are used for ordinal and nominal data, whereas nonparametric tests are used for interval and ratio data. C) Parametric tests are used for ordinal or interval data, whereas nonparametric 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. - Answer- parametric tests are used for interval and ratio data, whereas nonparametric tests are used for nominal and ordinal data The sign test is used as a nonparametric alternative to which parametric test? A) one-sample t-test B) two-independent sample t-test C) related samples t-test D) both A and C - Answer- both A and C We convert r to a t statistic for which of the following correlation tests? A) Pearson B) Spearman C) point-biserial D) phi - Answer- point-biserial We convert r to a chi-square statistic for which of the following correlation tests? A) Pearson B) Spearman C) point-biserial D) phi - Answer- phi A researcher measures the following correlation between number of years of education and life satisfaction: r = +0.08. What is the value of the coefficient of determination? A) 0.08 B) 0.16 C) 0.01 D) 0.11 - Answer- 0.01 The appropriate correlation coefficient for measuring for the direction and strength of the linear relationship between two dichotomous variables is A) the Spearman rank-order correlation coefficient B) the point-biserial correlation coefficient C) the phi correlation coefficient D) none of the above - Answer- the phi correlation coefficient A researcher measures the relationship between two variables, X and Y. If = 340 and = 320,000, then what is the value of the correlation coefficient? A) 0.32 B) 0.34 C) 0.60 D) almost a zero correlation - Answer- 0.60 A researcher observes a correlation of values from 2 to 10 points and draws conclusions about the full range of values in the population from 0 to 21 points. Which limitation for correctly interpreting a correlation coefficient did the researcher violate? A) reverse causality B) restriction of range C) a confound variable D) homoscedasticity - Answer- restriction of range Which of the following indicates the strongest correlation? A) r = -0.57 B) r = +0.78 C) r = -0.90 D) r = +0.88 - Answer- r = -0.90 The correlation coefficient ranges from -1.0 to +1.0, with values closer to ±1.0 indicating A) a more positive relationship between two factors B) a stronger relationship between two factors C) that two factors are less likely to be related D) that the correlation is due to outliers - Answer- a stronger relationship between two factors A scientist finds two results. Result #1 is that higher education is associated with a larger annual income. Result #2 is that fewer calories consumed is associated with less visits to the doctor. How would you characterize these two results? A) Result #1 shows a positive correlation and result #2 shows a negative correlation. B) Result #1 shows a negative correlation and result #2 shows a positive correlation. C) Both results show a negative correlation. D) Both results show a positive correlation. - Answer- both results show a positive correlation An unanticipated variable not accounted for in a research study that could be causing or associated with observed changes in one or more measured variables is called A) reverse causality B) restriction of range C) a confound variable D) homoscedasticity - Answer- a confound variable The point-biserial correlation coefficient is a measure of the direction and strength of the linear relationship between two variables, where A) one is continuous, and one is dichotomous B) both variables are on an ordinal scale C) one is at interval level or higher and one is ordinal D) both variables are on a nominal scale - Answer- one is continuous, and one is dichotomous A researcher measures the correlation of the time it takes participants to complete two tasks purported to measure the same cognitive skill. Participant times are converted to ranks from fastest to slowest. If = 165 and n = 20, then what is the decision for this correlation test? A) Retain the null hypothesis because the critical value exceeds the calculated value. B) Reject the null hypothesis because the calculated value exceeds the critical value. C) Retain the null hypothesis because the calculated value exceeds the critical value. D) Reject the null hypothesis because the critical value exceeds the calculated value. - Answer- reject the null hypothesis because the calculated value exceeds the critical value