Hi., Lets take two case,

Case_1: p = 0.9 then odd_1 = 0.9/0.1 =9

Case_2: p = 0.5 then odd_2 = 0.5/0.5 = 1

now odd ratio = 9/1 = 1 which violates the range [0,1].

Am I missing something ?

Covariance is the concept of variance to multiple random variables. Instead of measuring the fluctuation of a single random variable, the covariance measures the fluctuation of two variables with each other.

- Var[X+Y] = Var[X] + Var[Y] + 2.XY.Cov(X,Y) ?

A **Random variable** is a variable whose **value** **is determined** by some **random event**. The **Expectation of random variable** ‘X’ i.e. E[X] is the **central tendency** of X when **picked once randomly** from the **sample space** (i.e. a homogeneous/ heterogeneous space of all possible outcome).

- E[X+c] = ?