height, weight, speed, time, revenue, etc.). conversion rate or event rate) or difference of two means (continuous data, e.g. This statistical significance calculator allows you to perform a post-hoc statistical evaluation of a set of data when the outcome of interest is difference of two proportions (binomial data, e.g.

P-value and significance for relative difference in means or proportions.

How to interpret a statistically significant result / low p-value.

What is 'p-value' and 'significance level'.

If this is above alpha, then she would fail to reject her null hypothesis. Then she would reject her null hypothesis, which Would compare this p value to her preset significance Our p value would be approximately 0.053. Our sample size is seven so our degrees of freedom would be six. And then our degrees of freedom, that's our sample size minus one. It's an approximation of negative infinity, very, very low number. It to be negative infinity and we can just call Would go to 2nd distribution and then I would use the t cumulative distribution function so let's go there, that's the number six I'm gonna do this with a TI-84, at least an emulator of a TI-84. Is more than 1.9 below the mean so this right What is the probability of getting a t value that Of the t distribution, what we are curious about,īecause our alternative hypothesis is that the T distribution really fast, and if this is the mean So, if we think about a t distribution, I'll try to hand draw a rough The way we get that approximation, we take our sample standard deviation and divide it by the square Is equal to her sample mean, minus the assumed meanįrom the null hypothesis, that's what we have over here, divided by and this is a mouthful, our approximation of the standard error of the mean. The way she would do that or if they didn't tell us ahead From that, she wouldĬalculate her sample mean and her sample standard deviation, and from that, she wouldĬalculate this t statistic. Miriam takes a sample, sample size is equal to seven. That the true mean is 18, the alternative is that it's less than 18. Some population here and the null hypothesis is

To remind ourselves what's going on here before I go aheadĪnd calculate the p value. Value for Miriam's test? So, pause this video and see if you can figure this out on your own. Assume that the conditionsįor inference were met. Her test statistic, IĬan never say that right, was t is equal to negative 1.9. Testing her null hypothesis that the population mean of some data set is equal to 18 versus herĪlternative hypothesis is that the mean is less than 18 with a sample of seven observations.

Hypothesis test calculator t score