In: Statistics and Probability
This problem has several parts.
The table below shows the ages and bone densities for five women.
Age | 40 | 42 | 47 | 51 | 50 |
---|---|---|---|---|---|
Bone Density | 340 | 335 | 319 | 319 | 310 |
Enter the slope and y-intercept of the regression line, using age as the independent variable. Round your answers to two decimal places. | ||||
Slope: | Intercept: | |||
Using your regression line (with rounded coefficients), predict the bone density of a 53-year-old woman to the nearest whole number. | ||||
Estimate: | ||||
Did you just perform interpolation or
extrapolation? A. interpolation B. extrapolation |
||||
Enter r for this data, each rounded to the nearest hundredth. | ||||
Correlation: |
ΣX | ΣY | Σ(x-x̅)² | Σ(y-ȳ)² | Σ(x-x̅)(y-ȳ) | |
total sum | 230 | 1623 | 94 | 621.2 | -226.00 |
mean | 46.00 | 324.60 | SSxx | SSyy | SSxy |
sample size , n = 5
here, x̅ = Σx / n= 46.00 ,
ȳ = Σy/n = 324.60
SSxx = Σ(x-x̅)² = 94.0000
SSxy= Σ(x-x̅)(y-ȳ) = -226.0
estimated slope , ß1 = SSxy/SSxx =
-226.0 / 94.000 =
-2.40
intercept, ß0 = y̅-ß1* x̄ =
435.20
so, regression line is Ŷ =
435.20 + -2.40 *x
......................
Predicted Y at X= 53
is
Ŷ = 435.19574 +
-2.404255 * 53 =
308
.................
A. interpolation
....................
correlation coefficient , r = Sxy/√(Sx.Sy) = -0.94
.................
THANKS
revert back for doubt
please upvote