In: Statistics and Probability
A pediatrician wants to determine the relation that may exist between a child's height and head circumference. She randomly selects 5 children and measures their height and head circumference. The data are summarized below. Complete parts (a) through (f) below.
Height (inches), x |
25 |
27 |
26.5 |
27.5 |
25.5 |
|
---|---|---|---|---|---|---|
Head Circumference (inches), y |
16.9 |
17.5 |
17.3 |
17.5 |
17.1 |
(a) Treating height as the explanatory variable, X, use technology to determine the estimates of β0 and β1.
β0 ≈b0 = ____ (Round to two decimal places as needed.)
β1 ≈b1 = ____ (Round to two decimal places as needed.)
(b) Use technology to compute the standard of the estimate , se.
se= ______ ( Rounding to four decimal places)
(c) A normal probability plot suggests that the residuals are normally distributed . Use technology to determine sb1 .
Sb1= _____ ( Rounding to four decimal places)
(d) A normal probability plot suggests that the residuals are normally distributed. Test whether a linear relation exists between height and head circumference at the α=0.01 level of significance.
The first step is to set up a hypothesis test. The parameter being tested is the slope, β1, of the linear regression line. If there is no linear relation between the response and explanatory variables, the slope of the true regression line will be zero.
The P-value for this test is _____ (rounding to three decimal places.)
(e) Use technology to construct a 95% confidence interval about the slope of the true least-squares regression line.
Lower bound: ____
Upper bound : _____
(f) Suppose a child has a height of 27 inches. What would be a good guess for the child's headcircumference?
Substitute the given height, 27 inches, for x in the regression line and simplify, rounding to two decimal places.
Y= ______
a)
bo=10.777
b1=0.247
b)se =0.0597
c)sb1=0.0288
d) P-value for this test is 0.003
e) Lower bound: =0.155
upper bound: =0.338
f)
Y =10.777+0.247*27=17.45 ( please try 17.43 if this comes wrong)