P-value Calculator

About P-value Calculator

A P-value calculator is used to determine the statistical significance of an observed result in hypothesis testing. It takes as input the observed test statistic, the null hypothesis, and the relevant parameters of the statistical test (such as degrees of freedom), and computes the p-value. The p-value represents the probability of obtaining results as extreme as, or more extreme than, the observed data, assuming the null hypothesis is true. A lower p-value suggests stronger evidence against the null hypothesis, indicating that the observed result is unlikely to have occurred by random chance alone. The calculated p-value is used in comparison with a predefined significance level (alpha) to make decisions about the null hypothesis. If the p-value is less than or equal to alpha, typically 0.05, the results are considered statistically significant, leading to the rejection of the null hypothesis in favor of the alternative hypothesis. If the p-value is greater than alpha, there is insufficient evidence to reject the null hypothesis.

Frequently Asked Questions (FAQ)

How do I calculate p-value?
The p-value is calculated by determining the probability of observing a test statistic as extreme as, or more extreme than, the observed one under the assumption of the null hypothesis.
What is p-value in Z test?
In a Z-test, the p-value is the probability of observing a Z-statistic as extreme as, or more extreme than, the calculated one, assuming a normal distribution and under the null hypothesis.
What is the p-value?
The p-value, or probability value, is a measure in statistics that quantifies the strength of evidence against a null hypothesis. It indicates the likelihood of observing a test statistic as extreme as, or more extreme than, the one obtained from the data, assuming the null hypothesis is true.
What is the alpha for p-value?
The alpha (α) for a p-value is the chosen level of significance that determines the threshold for rejecting the null hypothesis. It represents the maximum probability of making a Type I error (incorrectly rejecting a true null hypothesis) and is typically set at common values such as 0.05 or 0.01.
What does p-value under 0.05 mean?
A p-value under 0.05 typically suggests that there is statistically significant evidence to reject the null hypothesis in favor of an alternative hypothesis.

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