Question

1. All of the following are true except B. A. A random variable represents a numerical value assigned to an outcome of a probability experiment. In most applications, discrete random variables represent counted data. C. In most applications, continuous random variables represent measured data. D. The expected value of a discrete random variable is equal to the standard deviation of the random variable.

Answer 1

The true statements are :

A. A random variable is a numerical description of the outcome of a statistical experiment.

B. In most​ applications, discrete random variables represent counted​ data.

C. In most applications, continuous random variables represent measured data.

Explanation:

It is true statement that,

A. A random variable is a numerical description of the outcome of a statistical experiment.

B. In most​ applications, discrete random variables represent counted​ data.

C. In most applications, continuous random variables represent measured data.

The false statement is -

D. The expected value of a discrete random variable is equal to the standard deviation of the random variable.

Reason -

The mean value, or expected value, of a discrete random variable X is given by the following equation:

μ = E(x) = ∑ x p(x)

And

The variance of a discrete random variable is given by the following formula:

σ²=∑ (x−μ)² P(x)

And

The square root of the variance, or, in other words, the square root of σ², is the standard deviation of a discrete random variable :

σ = √σ²