STAT XL 10
Introduction to Statistical Reasoning
Instructor: Ivo Dinov, Asst. Prof.
Departments of Statistics & Neurology
Wednesday, May 22, 2002, turn in before lecture
HW submission rules
. On the front page include the
- (HW_3_1) Compute the correlation coefficient, R(X,Y), for the following data. Interpret your result. Please do this by hand and show all of your
work. Find a linear equation, a line lo, which describes the best linear regression fit
(least squares fit) of Y on X. If we have two other candidate lines, l1 and l2, each with residual square error (RSE ) of 123 and 153, respectively. Compute the RSE for the best (least squares) line you computed, lo, and rank the three lines best to worst fit. What is your ranking criterion?
What is the correlation R(Y, X)? R(3X-2.2 , -4Y +7)?
- (HW_3_2) Find the equation of the line, l1,
passing through the points (-3, 5) and (1, 2). Identify the slope,
m1, and Y-intercept, b1, of the
line. A line, l2, is perpendicular to l1 if
its slope is -1/m1. Find the equation
of the line, l2, perpendicular to l1, which
goes through the point (X=0, Y=3). What are l2's slope,
m2, and Y-intercept, b2?
\Ivo D. Dinov, Ph.D., Departments of Statistics and Neurology, UCLA School