Question

A) A poll shows 60% of voters support Proposition A. 25 people were surveyed.

A politician claims the actual support is 50% What would be the null hypothesis?

B) What would be the alternative hypothesis?

C) What kind of test are we looking at?

D) Find the critical value.

Answer 1

Here in this scenario we surveyed the 25 randomly selected people's out of these 60% people's support the proposition A. That means out of 25 people 15 support the proposition A.

A politician claims that the actual proportion of support to proportion A is 50%. We have to test this claim, in this case our claim is that the proportion of support to proportion A is not equal to 50%.

To test our claim we have to use one population proportion z test.

A) The null hypothesis is,

Ho : The proportion is equal to 50%.

Ho : P = 0.50.

B) The alternative hypothesis is,

Ha : The proportion of people who support proportion A is not equal to 50%.

Ha : P =×= 0.50.

C) To test this claim we have to use z test for one population proportion.

D) The critical value is calculated using following steps,

Here the level of significance is not specified or not mentioned we assuming that the level of significance is equal to 0.05.

Z cri = 1.96 at 0.05 level of significance.

Further the test is performed at 0?05 assumed level of significance as below,

The z critical value is calculated using Standerd normal z-table or using Excel.

Thank you.