Conditional Probability

It’s NOT just both events happened, it’s asking the probability of one event AFTERanother event happened.
It’s based on a happened event, that’s why you’re to divide the probability of the happened event.

Notation

Least-square Regression

Least-square Regression is one way of calculating _Linear Regression_. 
Most regressions’ calculations are done by computer, but we want to do that by hand to have better understanding.

Scatter Plot

Just to plot many dots on the X-Y plane.

Linear & Non-linear Relationship

Probability Rules

Multiplication Rule (A and B)

The probability of multiple events occur at the same time is the multiplication of their probabilities.

Addition Rule (A or B)

Bayes' Theorem (Basics)

The Bayes’ Theorem is a revolution to conditional probability.

It does not intent to do once calculation, but is a progress of improving: each time gain a little bit more confidence.

R² (Coefficient of Determinator)

R-squared means Squared Residuals, which is the SE (Standard Error).

R squared is ALWAYS between 0 and 1, and the higher your R squared, the better.

Probability

Theoretical Probability vs. Experimental Probability

The experimental probability should get closer and closer to the theoretical probability after trying more and more times.

• Theoretical Probability: It's what's expected…