What is a discrete random variable in statistics?

A variable is a quantity whose value changes. A discrete variable is a variable whose value is obtained by counting. A discrete random variable X has a countable number of possible values. Example: Let X represent the sum of two dice.

What is standard deviation of a discrete random variable?

A measure of spread for a distribution of a random variable that determines the degree to which the values differ from the expected value. The standard deviation of random variable X is often written as σ or σX.

What is a standard random variable?

A standard normal random variable is a normally distributed random variable with mean μ=0 and standard deviation σ=1. It will always be denoted by the letter Z.

Is 1.5 a discrete variable?

Discrete random variables. If the possible outcomes of a random variable can be listed out using a finite (or countably infinite) set of single numbers (for example, {0, 1, 2 . . . , 10}; or {-3, -2.75, 0, 1.5}; or {10, 20, 30, 40, 50…} ), then the random variable is discrete.

What is the expected value for a random variable?

Definition (informal) The expected value of a random variable is the weighted average of the values that can take on, where each possible value is weighted by its respective probability.

What is continuous random variable stats?

A continuous random variable is a random variable where the data can take infinitely many values. For example, a random variable measuring the time taken for something to be done is continuous since there are an infinite number of possible times that can be taken.

What is discrete and continuous random variables?

Discrete variables are the variables, wherein the values can be obtained by counting. On the other hand, Continuous variables are the random variables that measure something. Discrete variable assumes independent values whereas continuous variable assumes any value in a given range or continuum.

What is discrete random variance?

Variance (of a discrete random variable) A measure of spread for a distribution of a random variable that determines the degree to which the values of a random variable differ from the expected value. The variance of random variable X is often written as Var( X) or σ 2 or σ 2x. For a discrete random variable the variance is calculated by…