In: Statistics and Probability
The data in the accompanying table represent the heights and weights of a random sample of professional baseball players. Complete parts (a) through (c) below.
Player Height_(inches)
Weight_(pounds)
Player_1 76 227
Player_2 75 197
Player_3 72 180
Player_4 82 231
Player_5 69 185
Player_6 74 190
Player_7 75 228
Player_8 71 200
Player_9 75 230
(b) Determine the least-squares regression line. Test whether there is a linear relation between height and weight at the
alphaαequals=0.05
level of significance.
Determine the least-squares regression line. Choose the correct answer below.
A.
ModifyingAbove y with caretyequals=4.1604.160xnegative 103.7−103.7
B.
ModifyingAbove y with caretyequals=8.160xnegative−101.7
C.
ModifyingAbove y with caretyequals=negative 101.7−101.7xplus+4.1604.160
D.
ModifyingAbove y with caretyequals=4.1604.160xnegative 101.7−101.7
Test whether there is a linear relation between height and weight at the
alphaαequals=0.05
level of significance.
State the null and alternative hypotheses. Choose the correct answer below.
A.
Upper H 0H0:
beta 1β1equals=0
Upper H 1H1:
beta 1β1not equals≠0
B.
Upper H 0H0:
beta 0β0equals=0
Upper H 1H1:
beta 0β0not equals≠0
C.
Upper H 0H0:
beta 0β0equals=0
Upper H 1H1:
beta 0β0greater than>0
D.
Upper H 0H0:
beta 1β1equals=0
Upper H 1H1:
beta 1β1greater than>0
Determine the P-value for this hypothesis test.
P-valueequals=nothing
(Round to three decimal places as needed.)
State the appropriate conclusion at the
alphaαequals=0.05
level of significance. Choose the correct answer below.
A.Do not reject
Upper H 0H0.
There is not sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
B.Do not reject
Upper H 0H0.
There is sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
C.Reject
Upper H 0H0.
There is not sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
D.Reject
Upper H 0H0.
There is sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
(c) Remove the values listed for Player 4 from the data table. Test whether there is a linear relation between height and weight. Do you think that Player 4 is influential?
Determine the P-value for this hypothesis test.
P-valueequals=nothing
(Round to three decimal places as needed.)
State the appropriate conclusion at the
alphaαequals=0.05
level of significance. Choose the correct answer below.
A.Reject
Upper H 0H0.
There is not sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
B.Do not reject
Upper H 0H0.
There is not sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
C.Do not reject
Upper H 0H0.
There is sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
D.Reject
Upper H 0H0.
There is sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
Do you think that Player 4 is influential?
Yes
No
ΣX | ΣY | Σ(x-x̅)² | Σ(y-ȳ)² | Σ(x-x̅)(y-ȳ) | |
total sum | 669.00 | 1868.00 | 108.00 | 3594.22 | 449.33 |
mean | 74.33 | 207.56 | SSxx | SSyy | SSxy |
.
sample size , n = 9
here, x̅ = Σx / n= 74.333
ȳ = Σy/n = 207.556
SSxx = Σ(x-x̅)² = 108.0000
SSxy= Σ(x-x̅)(y-ȳ) = 449.3
estimated slope , ß1 = SSxy/SSxx =
449.3333/108= 4.16049
intercept,ß0 = y̅-ß1* x̄ = 207.5556- (4.1605
)*74.3333= -101.70782
b)
D. Y^=4.160*X −101.7
c)
Ho: β1= 0
H1: β1╪ 0
estimated std error of slope =Se(ß1) = Se/√Sxx =
15.697/√108= 1.5104
t stat = estimated slope/std error =ß1 /Se(ß1) =
(4.1605-0)/1.5104= 2.7545
Degree of freedom ,df = n-2= 7
t-critical value= 2.3646 [excel function:
=T.INV.2T(α,df) ]
p-value = 0.028
D.Reject
Upper H 0H0.
There is sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
c)
p value=0.053
B.Do not reject Ho.
There is not sufficient evidence to conclude that a linear relation exists between the height and weight of baseball players.
YES, influential