In: Statistics and Probability
When an anthropologist finds skeletal remains, they need to figure out the height of the person. The height of a person (in cm) and the length of their metacarpal bone (in cm) were collected for 19 randomly selected sets of skeletal remains and are in the table below. Test at the 10% level for a positive correlation between length of metacarpal and height for sets of skeletal remains.
length of metacarpal | height |
---|---|
41 | 162 |
48 | 174 |
46 | 173 |
42 | 165 |
46 | 175 |
43 | 177 |
43 | 170 |
38 | 157 |
47 | 172 |
51 | 180 |
42 | 161 |
50 | 178 |
44 | 171 |
42 | 175 |
49 | 185 |
40 | 155 |
40 | 160 |
48 | 183 |
44 | 173 |
T: Test Statistic
t = 6.63
O: Obtain the P-value
Report the final answer to 4 decimal places.
It is possible when rounded that a p-value is 0.0000
P-value = 0.0000
M: Make a decision
S: State a conclustion
x | y | (x-x̅)² | (y-ȳ)² | (x-x̅)(y-ȳ) |
41 | 162 | 11.70 | 78.18 | 30.25 |
48 | 174 | 12.81 | 9.97 | 11.30 |
46 | 173 | 2.49 | 4.66 | 3.41 |
42 | 165 | 5.86 | 34.13 | 14.14 |
46 | 175 | 2.49 | 17.29 | 6.57 |
43 | 177 | 2.02 | 37.92 | -8.75 |
43 | 170 | 2.02 | 0.71 | 1.20 |
38 | 157 | 41.23 | 191.60 | 88.88 |
47 | 172 | 6.65 | 1.34 | 2.99 |
51 | 180 | 43.28 | 83.87 | 60.25 |
42 | 161 | 5.86 | 96.87 | 23.83 |
50 | 178 | 31.12 | 51.24 | 39.93 |
44 | 171 | 0.18 | 0.02 | -0.07 |
42 | 175 | 5.86 | 17.29 | -10.07 |
49 | 185 | 20.97 | 200.45 | 64.83 |
40 | 155 | 19.55 | 250.97 | 70.04 |
40 | 160 | 19.55 | 117.55 | 47.93 |
48 | 183 | 12.81 | 147.81 | 43.51 |
44 | 173 | 0.18 | 4.66 | -0.91 |
ΣX | ΣY | Σ(x-x̅)² | Σ(y-ȳ)² | Σ(x-x̅)(y-ȳ) | |
total sum | 844 | 3246 | 246.6315789 | 1346.526 | 489.263 |
mean | 44.421 | 170.842 | SSxx | SSyy | SSxy |
correlation coefficient , r = Sxy/√(Sx.Sy)
= 0.849
Ho: ρ = 0
Ha: ρ > 0
n= 19
alpha,α = 0.1
correlation , r= 0.8490
t-test statistic = r*√(n-2)/√(1-r²) =
6.63
DF=n-2 = 17
p-value = 0.0000
Since the p-value ≤____α=0.10_____ , we reject H₀
There is significant evidence to conclude there is a positive linear