For a two-tailed hypothesis test, the test statistic is z = 1.42. What is the p-value?
P-value = 2(1-.9222) = 0.1556
To determine the p-value for a two-tailed hypothesis test, you need to find the probability of observing a test statistic as extreme as the one calculated, assuming the null hypothesis is true.
Since you have a z-test statistic, you will use a standard normal distribution (z-distribution) to find the p-value.
In this case, since the test is two-tailed, you are interested in both tails of the distribution. The p-value is calculated as the combined value of both tails.
To find the p-value, you can follow these steps:
1. Determine the area in one tail:
- You have a z-value of 1.42, which is the number of standard deviations away from the mean. Find the area under the standard normal curve to the left of 1.42. You can use a standard normal table or a calculator to find this area. Let's assume it is A.
2. Calculate the p-value for one tail:
- Since the test is two-tailed, the area in one tail corresponds to one-half of the p-value. So, the p-value for one tail is p = (A/2).
3. Calculate the p-value for both tails:
- Since the test is two-tailed, we need to consider both tails. The p-value for both tails is p = 2 * (p-value for one tail).
Therefore, to find the p-value, you should follow these steps:
1. Find the area in one tail using a standard normal table or calculator.
2. Divide the area by 2 to find the p-value for one tail.
3. Multiply the p-value for one tail by 2 to get the p-value for both tails.
By following these steps, you should be able to calculate the p-value for the given z-test statistic.