# What does t test and p-value tell you?

## What does t test and p-value tell you?

In this way, T and P are inextricably linked. Consider them simply different ways to quantify the “extremeness” of your results under the null hypothesis. The larger the absolute value of the t-value, the smaller the p-value, and the greater the evidence against the null hypothesis.

How do you find p-value from test statistic?

How to calculate p-value from test statistic?

1. Left-tailed test: p-value = cdf(x)
2. Right-tailed test: p-value = 1 – cdf(x)
3. Two-tailed test: p-value = 2 * min{cdf(x) , 1 – cdf(x)}

### How do you find t value in statistics?

Calculate the T-statistic Subtract the population mean from the sample mean: x-bar – μ. Divide s by the square root of n, the number of units in the sample: s ÷ √(n).

How do you calculate p-value from correlation?

Calculation Notes:

1. You will use technology to calculate the p-value.
2. The p-value is calculated using a t-distribution with n – 2 degrees of freedom.
3. The formula for the test statistic is t=r√n−2√1−r2 t = r n − 2 1 − r 2 .
4. The p-value is the combined area in both tails.

## How do you determine the p value?

Steps Determine your experiment’s expected results. Determine your experiment’s observed results. Determine your experiment’s degrees of freedom. Compare expected results to observed results with chi square. Choose a significance level. Use a chi square distribution table to approximate your p-value.

What does p value tell you?

A p-value can tell you that a difference is statistically significant, but it tells you nothing about the size or magnitude of the difference. “The p-value is low, so the alternative hypothesis is true.”.

### How do you find the p value of a test statistic?

The p-value is calculated using the sampling distribution of the test statistic under the null hypothesis, the sample data, and the type of test being done (lower-tailed test, upper-tailed test, or two-sided test). The p-value for: a lower-tailed test is specified by: p-value = P(TS ts | H 0 is true) = cdf(ts)

How do you find the p value in statistics?

As said, when testing a hypothesis in statistics, the p-value can help determine support for or against a claim by quantifying the evidence. The Excel formula we’ll be using to calculate the p-value is: =tdist(x,deg_freedom,tails)