Authors: Jay L. Devore
ISBN-13: 978-1305251809
See our solution for Question 1E from Chapter 14 from Devore's Probability and Statistics for Engineering and Science.
(a)
Given,
The level of significance is $\alpha = 0.05$.
The degrees of freedom is 4.
The calculated value of the test statistic is, ${\chi ^2} = 12.25$.
The null and alternative hypotheses are follows,
\[\begin{array}{l} {H_0}:{p_1} = ... = {p_n}\\ {H_1}:{\rm{ Atleast\;one\;}}{p_i}{\rm{\;does\;not\;equal}}{\rm{.}} \end{array}\]Now calculate the p-value by using significance level and degrees of freedom.
Therefore, the p-value is 0.0156.
It is clear that, the p-value is less than the value of significance level.
That is, $0.0156 < 0.05$.
Hence, reject the null hypothesis at significance level 0.05.
(b)
Given,
The level of significance is $\alpha = 0.01$.
The degrees of freedom is 3.
The calculated value of the test statistic is, ${\chi ^2} = 8.54$.
The null and alternative hypotheses are follows,
\[\begin{array}{l} {H_0}:{p_1} = ... = {p_n}\\ {H_1}:{\rm{ Atleast\;one\; }}{p_i}{\rm{ \;does \;not \;equal}}{\rm{.}} \end{array}\]Now calculate the p-value by using significance level and degrees of freedom.
Therefore, the p-value is 0.0361.
It is clear that, the p-value is greater than the value of significance level.
That is, $0.0361 > 0.01$.
Hence, fail to reject the null hypothesis at significance level 0.01.
(c)
Given,
The level of significance is $\alpha = 0.10$.
The degrees of freedom is 2.
The calculated value of the test statistic is, ${\chi ^2} = 4.36$.
The null and alternative hypotheses are follows,
\[\begin{array}{l} {H_0}:{p_1} = ... = {p_n}\\ {H_1}:{\rm{ Atleast \;one\; }}{p_i}{\rm{ \;does \;not \;equal}}{\rm{.}} \end{array}\]Now calculate the p-value by using significance level and degrees of freedom.
Therefore, the p-value is 0.1130.
It is clear that, the p-value is greater than the value of significance level.
That is, $0.1130 > 0.10$.
Hence, fail to reject the null hypothesis at significance level 0.10.
(d)
Given,
The level of significance is $\alpha = 0.01$.
The number of observations is, $k = 6$.
The calculated value of the test statistic is, ${\chi ^2} = 10.20$.
The null and alternative hypotheses are follows,
\[\begin{array}{l} {H_0}:{p_1} = ... = {p_n}\\ {H_1}:{\rm{ Atleast \;one\; }}{p_i}{\rm{ \;does \;not \;equal\;}}{\rm{.}} \end{array}\]Now, calculate the degrees of freedom is given below,
\[\begin{array}{c} df = k - 1\\ = 6 - 1\\ = 5 \end{array}\]Also, calculate the p-value by using significance level and degrees of freedom.
Therefore, the p-value is 0.0698.
It is clear that, the p-value is greater than the value of significance level.
That is, $0.0698 > 0.01$.
Hence, fail to reject the null hypothesis at significance level 0.01.