In: Math
In 1950, an organization surveyed 1100 adults and asked, "Are you a total abstainer from, or do you on occasion consume, alcoholic beverages?" Of the 1100 adults surveyed, 363 indicated that they were total abstainers. In a recent survey, the same question was asked of 1100 adults and 319 indicated that they were total abstainers. Has the proportion of adults who totally abstain from alcohol changed? Use the α = 0.01 level of significance. Normality criteria have been satisfied.
Write the Null and Alternative Hypothesis:
Give the Test statistic and P value:
State the conclusion in context:
p1 : Population proportion of adults who totally abstain from alcohol when surveyed in 1950
p2 : Population proportion of adults who totally abstain from alcohol in recent survey
Null hypothesis Ho: p1 = p2
Alternate hypothesis :Ha p1 p2
Since the null hypothesis states that p1=p2, we use a pooled sample proportion () to compute the standard error of the sampling distribution.
Given | |
n1 : Sample Size of survey in 1950 | 1100 |
n2 : Sample Size of recent survey | 1100 |
x1: Number of adults indicated that they were total abstainers from the survey in 1950 | 363 |
x2: Number of adults indicated that they were total abstainers from the recent survey | 319 |
: Sample Propotion of adults indicated that they were total abstainers from the survey in 1950 | 0.33 |
: Sample Propotion of adults indicated that they were total abstainers from the recent survey | 0.29 |
Level of Significance | 0.01 |
Two Tailed Test: P-value :
As P-Value i.e. is greater than Level of significance i.e (P-value:0.0425 > 0.01:Level of significance); Fail to Reject Null Hypothesis
At , 0.01 level of significance , the evidence is not sufficent to reject that the proportion of adults who totally abstain from alcohol has not changed