91影视

The mean is the sum of all values divided by the number of values:

$n$is the number of values in the data set?

The standard deviation is the square root of the sum of squared deviations from the mean divided by $n-1$:

$s_1=3.1093$

$s_2=3.9256$

Determine the hypothesis:

$H_0:{渭}_1={渭}_2$

$H_a:{渭}_1<{渭}_2$

Determine the test statistic:

localid="1650516568809" $$\begin{gathered} t=\frac{{\stackrel{炉}{x}}_1-{\stackrel{炉}{x}}_2}{\sqrt{\frac{s_1^2}{n_1}+\frac{s_2^2}{n_2}}} \\ =\frac{4-11.3}{\sqrt{\frac{3.{1093}^2}{6}+\frac{3.{9256}^2}{7}}} \\ 鈮�-3.739 \end{gathered}$$

Determine the degrees of freedom:

localid="1650516589517" $$\begin{gathered} df=\min \left(n_1-1,n_2-1\right) \\ =\min (7-1,6-1) \\ =5 \end{gathered}$$

The P-value is the probability of obtaining the value of the test statistic, or a value more extreme. The P-value is the number (or interval) in the column title of Table B containing the t-value in the row$鈭�df=5$:

$0.005<P$$<0.01$

If the P-value is less than or equal to the significance level, then the null hypothesis is rejected:

$P<0.05鈬�\text{Reject}{H}_0$