I need help doing a prediction for a graphic
problem have must predict the mathematics score
for a science score of 50.
the graph is a class of students science and math
scores from 1985-89-on the left side of graph is
science scores from 70 down to 40 math scores on
both of graph 40 thru 80...
yr-1985 math score 60 science 65
yr-1986 " " 53 " 65
yr-1987 " " 44 " 57
yr-1988 " " 61 " 61
yr-1989 " " 70 " 67
How do i predict the math score of correspondending
science score of 50? and how would i predict the
science of corresponding math score of 65?
We form the regression line for the points
(60,65), (53,65), (44,57), (61,61), (70,67)
Look up the formula for m and b in your book
and then the equation of the regression line
is y = mx + b.
Plugging in the formulas, which are rather
complicated, you will get m = .318336161 and
b = 44.67550371. If you have trouble
plugging in those formulas then post again.
Sometimes books will use letter "a" instead of
"m".
y = .318336161x + 44.67550371
Then we plug in x = 50, and solve for y, and get
y = 60.59231176
Then we plug in 65 for y, and solve for x
x = 63.84601808
Edwin
