Question: Give a simple student reply to how well they explained the following: Step 1: Check assumptions Both samples are independent and of size 100 Proportions
Give a simple student reply to how well they explained the following: Step 1: Check assumptions
Both samples are independent and of size 100
Proportions are not too close to 0 or 1
All values of np and n(1p)are 5 Assumptions are met to use a z-test.
Step 2: State values
We calculate the pooled proportion under H0: p1= p2
p= x1+x2/n1+n2 = (0.40 x 100) + (0.35 x 100) / 200 = 40+35/200 = 75/200 = 0.375
Then the standard error under H0:
SE = p(1-p) (1/n1 + 1/n2) = 0.375(1-0.375) (1/100 + 1/100) = 0.375 x 0.625 x 2/100= 0.234375 x 0.02 = 0.0046875 = 0.0685
Now we compute the z-statistic:
z = p1-p2/SE = 0.40-0.35/0.0685 = 0.05/0.0685 = 0.73
Step 3: Find critical values
Since the alternative hypothesis is H1: p1 > p2, this is a right-tailed test.
At = 0.01, the critical z-value is: z0.01 = 2.33
At = 0.10, the critical z-value is:z0.10 = 1.28
Step 4: Make decisions
We compare our test statistic z = 0.73 to the critical values:
At = 0.01: 0.73 < 2.33 Fail to reject H0
At = 0.10: 0.73 < 1.28 Fail to reject H0
Empty heading
Final conclusion:
The assumptions for the z-test are satisfied.
The calculated z-statistic is approximately 0.73.
The critical values are:
2.33 at = 0.01
1.28 at = 0.10
Decision:
At = 0.01 Do not reject H0
At = 0.10 Do not reject H0
There is not enough evidence to support that p1>p2 at either significance level.
Step by Step Solution
There are 3 Steps involved in it
Get step-by-step solutions from verified subject matter experts
