# Test 2 practice

Although a biased estimator _______ is used to estimate ________ in large samples since the bias is relatively small

s, ? (sigma)

______________ is a statistic used to infer the value of population parameter

estimator

write all unbiased estimators

x? (bar x), s2 (s squared) p? (p hat)

The general behavior sampling distribution of the sample mean is

normal distribution

The general behavior of the sampling distribution of the sample variance is

skewed to the right

the expected value, E(x), of a probability distribution is also equal to

the mean

The sum of all probabilities in a probability distribution is

equal to 1

The sample proportion is denoted by

p hat

List the requirements of a binomial probability distribution

fixed number of trials, the trials must be independent, each trial must have all outcomes classified into exactly two categories, the probability of a success remains the same in all trials.

the variable "x" in a binomial probability distribution is a

Discrete random variable

A continuous random variable has a ____________ if its values are evenly spread over the range of possibilities.

uniform distribution

The graph of a continuous probability distribution is called a _________

probability density function

If a continuous random variable has a distribution with a graph that is symmetric and bell-shaped, we say that it has a _________ distribution

normal

List the parameters of the standard normal density curve and what they equal

Mean= 0
SD= 1

For the standard normal distribution a _________ is a z score separating unlikely values from those that are likely to occur

critical value