Answer:
The p-value obtained is less than the significance level at which the test was performed at, hence, we reject the null hypothesis, accept the alternative hypothesis & say that there is enough evidence to conclude that the the new medicine is potentially harmful.
Step-by-step explanation:
The null hypothesis plays the devil's advocate and usually takes the form of the opposite of the theory to be tested. It usually contains the signs =, ≤ and ≥ depending on the directions of the test.
While, the alternative hypothesis usually confirms the the theory being tested by the experimental setup. It usually contains the signs ≠, < and > depending on the directions of the test.
For this question, the null hypothesis is that the new medicine has no negative effects and the alternative hypothesis is that the new medicine is potentially harmful
Mathematically,
The null hypothesis is represented as
H₀: p = 0
The alternative hypothesis is represented as
Hₐ: p > 0
To do this test, we will use the z-distribution because although no information on the population standard deviation is known, the sample size is large enough.
So, we compute the test statistic
z = (x - μ)/σₓ
x = sample proportion = (31/3000) = 0.0103
μ = p₀ = 0
σₓ = standard error = √[p(1-p)/n]
where n = Sample size = 3000
σₓ = √[0.0103×0.9897/3000] = 0.0018462936 = 0.0018463
z = (0.0103 - 0) ÷ 0.0018463
z = 5.60
checking the tables for the p-value of this test statistic
Significance level = 1% = 0.01
The hypothesis test uses a one-tailed condition because we're testing only in one direction.
p-value (for z = 5.60, at 0.01 significance level, with a one tailed condition) = < 0.00001
The interpretation of p-values is that
When the (p-value > significance level), we fail to reject the null hypothesis and when the (p-value < significance level), we reject the null hypothesis and accept the alternative hypothesis.
So, for this question, significance level = 0.01
p-value = < 0.00001
p-value < 0.00001 < 0.10
Hence,
p-value < significance level
This means that we reject the null hypothesis, accept the alternative hypothesis & say that there is enough evidence to conclude that the the new medicine is potentially harmful.
Hope this Helps!!!
