Question

A nationwide sample of influential Liberals and Conservatives was asked as a part of a comprehensive survey whether they favoured lowering environmental standards so that high-sulphur coal could be burned in coal-fired power plants. The results were:

	Liberals	Conservatives
Number sampled	554	267
Number in favour	142	85

At the 0.02 level of significance, can we conclude that there is a larger proportion of Conservatives in favour of lowering the standards? Calculate and interpret the p-value.

a. State the decision rule. (Round the final answer to 3 decimal places.)

H₀ is rejected if z  (Click to select)  is more  is less  than   .

b. Compute the pooled proportion. (Round the final answer to 4 decimal places.)

Pooled proportion            

c. Compute the value of the test statistic. (Negative answer should be indicated by a minus sign. Round the final answer to 2 decimal places.)

Value of test statistic            

d. What is your decision regarding the null hypothesis?

Decision             (Click to select)  Reject  Do not reject

e. Calculate the p-value. (Round the z-value to 2 decimal places. Round the final answer to 4 decimal places.)

p-value is:

Answer 1

a)

The null and alternate hypothesis are:

H0:

Ha:

Since this is a left tailed test, so critical value is :

So, H0 is rejected if Z is less than -2.054

b)

Pooled proportion =

c)

Test statistic =

d)

Since the test statistic isn't less than -2.054, we do not have sufficient evidence to reject H0. So, we do not reject H0.

e)

Since this is a left tailed test, so p-value: