Chapter 14.4, Problem 8PS

In Problem 7–18, a sample of paired data gives a linear coefficient correlation r. In each case, use Table 14.10 to determine whether there is a significant linear correlation.

$n=30,r=0.4;1\%\text{ level}$

Table 14.10 Correlation Coefficient, $\mathit{r}$

$\mathit{n}$	$\mathit{\alpha }=0.05$	$\mathit{\alpha }=0.01$
4	0.950	0.999
5	0.878	0.959
6	0.811	0.917
7	0.754	0.875
8	0.707	0.834
9	0.666	0.798
10	0.632	0.765
11	0.602	0.735
12	0.576	0.708
13	0.553	0.684
14	0.532	0.661
15	0.514	0.641
16	0.497	0.623
17	0.482	0.606
18	0.468	0.590
19	0.456	0.575
20	0.444	0.561
25	0.396	0.505
30	0.361	0.463
35	0.335	0.430
40	0.312	0.402
45	0.294	0.378
50	0.279	0.361
60	0.254	0.330
70	0.236	0.305
80	0.220	0.266
90	0.207	0.269
100	0.196	0.256