I was watching this video on YouTube of simple linear regression equation, and he said that E(Y)=Beta0 + Beta1x + elipson, and said that there is a whole distribution for the possible Y values, and hence it's E(Y). I didn't get that why there is a whole distribution for y values, shouldn't it just be Y, because we are already accounting for the errors in elipson. Please help me.
Video Link:https://youtu.be/iAgYLRy7e20 The statement is made 12:40