Keynisha Kelson 021 03/ 2021 PSY 310 Date: Name: Due: 2-3-2022@2:30 am. In class 1) A developmental psychologist is interested in determining whether it is possible to use the self-esteem score to predict Popularity. To answer this question, she collected the following data: Subjec 49 121 38.5 6 r tom in - mint 125 17.5 49 24.51 135 220 A) Draw scatterplot of the data. (4 points). ......................................on one page. Use ruler to be more exact. B) Calculate "Ip" and interpret it (three interpretations). (4 points) C) Find the regression equation. (3 points). {Y' = b (X) + a} D) Draw the regression line (show your work on paper) on the scatterplot (3points) E) Predict test score for all individual in the sample (3 points) F) Predict y' score for X = 3.5 (1 point). G) Calculate coefficient of determination (r) (proportion of variance accounted for) and interpret it in TWO ways. (2 points) H) Calculate Variance ($2 ,) and standard deviation for Y scores Sy = VS, 2 and Why we calculate the standard deviation of y scores? (3 points) (Remember you can calculate variance in two ways: raw score method and deviation method.) I Calculate standard error of the estimate (Sy') in two ways: (3points) a. Use the following formulas: S?y, = S' y (1-r?) and Sy = VS, 2enter b. Use deviation method: S?y, = [(Y- Y' ) ? / N also given below and Sy = VS2y, c. Explain what standard error of the estimate means. (2 points) Scale for Strength of correlation: Weak (0.01 to 0.39), Moderate (0.40 to 0.79), Strong (0.80 to 0.99) N ( EXY ) - ( EX ) ( EY ) r = VIN ( EX ? ) - ( EX) ? ][ N ( EY? ) - (EY) =] 1. Computer. N ( EXY ) - ( EX ) ( EX ) 2. Compute the slope, b, where b = - N ( E X 2 ) - ( [ X ) ? 3 . Compute the Y intercept, a, where a = Y - (b) (X) WI 4. Substitute the values of a and b into the formula for the regression equation: Y' = ( b ) ( X ) + a 5. Plot the regression line. 6. Compute the predicted Y' score for any X. Raw S Lx = 12 2 You can use one of the following for variance of Y. Definitional method