# 22nd September 2023- Friday class

Today I have learnt about t-test. A t-test is like a detective tool in statistics. Imagine you have two groups of data, and you want to know if they are really different or if it’s just a coincidence. The t-test helps you find out. It starts with a guess called the “null hypothesis,” which says there’s no real difference between the groups. Then, you collect data and calculate a special number called “t-statistic.” This number shows how much the groups really differ. If the t-statistic is big and the groups are very different, you get a small “p-value,” which is like a clue. A small p-value suggests that the groups are probably different for real, not just by chance. If the p-value is smaller than a number you choose (usually 0.05), you can say the groups are different, and you reject the null hypothesis. But if the p-value is big, it means the groups might not be that different, and you don’t have enough evidence to reject the null hypothesis. So, the t-test helps you decide if what you see in your data is a real difference or just a trick of chance.