
The most common use comparison test between two subset of data

For Example try to make hypothesis that lefthand and righthand have no different batting average

ttest is used to approve or decline our null hypothesis, while ttest is parametric test in our statisitic significance test.

NULL Hypothesis, is hypothesis for our data to be asked, if both of our data is similar? or the sample acquired through data that drawn from normal distribution(same population).

By doing ttest we reduce all the comparison test to one number only, the t value

if only contain 1 sample, compare average, to average sample 0

if two samples, compare average 0 to average 1.

tvalue denotes how extreme our results, and probabilty it will reject out null hypothesis

the v value denotes how many variable took into t calculations


the p value produced by t and v, will then the value that will determine our hypothesis accepted based in our null hypothesis was true

suppose we want to know the difference batting avg left and right, giveb our null hypothesis both no different

then if pvalue 0.5, the variance between t and v at least 5% at extreme.

pcritical acts like some kind of threshold value. and it will determine whether our null hypothesis is accepted

this threshold value will be quite tedious if we set it manually. rather, it can be done automatically.

by specifyinhg equalvar=true, the calculations will be exactly the same as welch's ttest

it will return a tuple, t and p value

we can do it by comparing the sample with one another

for our null hypothesis set to true, p must be less than p critical

Basic implementation Welch's ttest with python