Confidence Intervals for Independent Samples With Unknown and Assumed Variance of the Population

00:01 Hi. And welcome back.

00:03 This is the last lesson about confidence intervals.

00:06 We are not going to get too deep into it, as it is just about knowing the formula.

00:12 Sometimes we want to find the confidence interval for two sample means when the samples are independent with unknown variances and the variances are assumed to be different.

00:23 You can think about comparing apples and oranges.

00:26 You've heard the expression, right? Well, in statistics, if you actually want to compare apples and oranges, this is the right way to do it.

00:35 Here's the confidence interval formula.

00:38 Once again, we have the differences of the means of the two samples.

00:42 The variances are the sample variances of each of the two variables, and here are the respective sample sizes.

00:50 The tough thing about this is to estimate the degrees of freedom.

00:55 Well, statisticians have come up with a formula that allows us to do just that. You have all the information, but it is highly unlikely that you will remember the formula.

01:06 All right. We won't give an example of this case, as it won't add any value to this course. In this video.

01:14 We just wanted to show you the right way to compare apples and oranges.

01:19 Next time we will get to the core of statistics hypothesis testing.

01:24 Don't miss out, and thanks for watching.