In: Statistics and Probability
In 2013, 30% of business owners gave a holiday gift to their employees. A 2014 survey of 53 business owners indicated that 19% plan to provide a holiday gift to their employees. Is there reason to believe the proportion of business owners providing gifts has decreased at a=0.05?
1)- What is/are the critical values?
2)- What is the test statistics?
3)- What is the conclusion?
Please explain in detail and step by step
Solution :
Given that,
= 0.30
1 - = 0.70
n = 53
Level of significance = = 0.05
Point estimate = sample proportion = = x / n = 0.19
This a left (One) tailed test.
The null and alternative hypothesis is,
Ho: p = 0.30
Ha: p < 0.30
Step - 1
Critical value of the significance level is α = 0.05, and the critical value for a two-tailed test is
= -1.645
Step - 2
Test statistics
z = ( - ) / *(1-) / n
= ( 0.19 - 0.30) / (0.30*0.70) / 53
= -1.768
Step - 3
Since it is observed that z = -1.768 < = -1.645 , it is then concluded that the null hypothesis is rejected.
Conclusion:
It is concluded that the null hypothesis Ho is rejected. Therefore, there is enough evidence to claim that the population proportion of business owners providing gifts has decreased at a=0.05 significance level.