In: Statistics and Probability
The data below shows the selling price (in hundred thousands) and the list price (in hundred thousands) of homes sold. Answer parts a-c.
Selling Price (x) |
403 |
302 |
379 |
434 |
455 |
477 |
316 |
350 |
417 |
330 |
|
List Price (y) |
410 |
317 |
389 |
439 |
486 |
480 |
320 |
365 |
432 |
a. Find the value of the linear correlation coefficient r.
b. Find the critical values of r from the table showing the critical values for the Pearson correlation coefficient using
alpha=0.05
c. Is there sufficient evidence to conclude that there is a linear correlation between the two variables?
Solution:
a)
X | Y | XY | X^2 | Y^2 | |
302 | 410 | 123820 | 91204 | 168100 | |
379 | 317 | 120143 | 143641 | 100489 | |
434 | 389 | 168826 | 188356 | 151321 | |
455 | 439 | 199745 | 207025 | 192721 | |
477 | 486 | 231822 | 227529 | 236196 | |
316 | 480 | 151680 | 99856 | 230400 | |
350 | 320 | 112000 | 122500 | 102400 | |
417 | 365 | 152205 | 173889 | 133225 | |
330 | 432 | 142560 | 108900 | 186624 | |
SUM | 3460 | 3638 | 1402801 | 1362900 | 1501476 |
Putting value , we get
r = 0.1318
b)
n = 9
df = n - 2 = 9 - 2 = 7
= 0.05
Using the critical value table for Pearson correlation coefficient, (two tailed )
Critical value are 0.666
c)
r = 0.1318
| r | = | 0.1318| = 0.1318
r < 0.666
Fail to reject H0
No significance correlation.
NO , there is NOT sufficient evidence to conclude that there is a linear correlation between the two variables.