stats ch 15 ufdgbiew DWEv8y0

(key vocabulary) Random variable

A variable that takes on numerical outcomes from a random process.

(key vocabulary) Discrete random variable

A random variable that takes on countable values; comes to a stop

(key vocabulary) Continuous random variable

A random variable that takes on any value in a continuous range; numbers dont stop

(key vocabulary) Standard Deviation

A measure of how spread out the values of a random variable are around the mean.

(key vocabulary) Expected value

The long-run mean value of a random variable.

(key vocabulary) E(X)

Notation for the expected value of the random variable X

(key vocabulary) V(X)

Notation for the variance of the random variable X, which is the square of the standard deviation.

A random variable is a numerical outcome of a random process.

Discrete random values come to a stop, continuous values continue indefinitely

all possible values of a random variable and their probabilities.

The expected value is the long-run average outcome of a random variable.

Multiply each outcome by its probability and sum them: E(X)=∑x_iP(x_i)

x̄ is the sample mean; 𝜇 is the population mean (expected value).