Statistics

Question 1

Statistic

Answer 1

A number that results from applying a mathematical function to a set of data

Question 2

Mean

Answer 2

The average of a set of numbers where each number is given the same weight.

Question 3

Median

Answer 3

The middle value in an ordered set of numbers.

Question 4

Mode

Answer 4

In a set of numbers, the value that occurs most frequently.

Question 5

Weighted Mean

Answer 5

The average of a set of numbers where each number can be given a different
weight.

Question 6

Standard deviation

Answer 6

The average amount by which a set of numbers deviates from its mean.

Question 7

Standard error

Answer 7

The standard deviation of an estimate (as opposed to the standard deviation of a
set of data).

Question 8

Variance

Answer 8

The standard deviation (or standard error) squared

Question 9

First Quartile

Answer 9

The value that separates the lowest 25% of a set of data from the rest. Similarly,
there are second, third, and fourth quartiles.

Question 10

First Decile

Answer 10

The value the separates the lowest 10% of a set of data from the rest. Similarly,
there are second, third, etc. deciles

Question 11

Range

Answer 11

The difference between the maximum and minimum values in a data set.

Question 12

Population mean

Answer 12

The mean of all observations in a population.

The population mean is usually represented as μ.

Question 13

Sample mean

Answer 13

The mean of all observations in a sample. The sample mean is an approximation
of the population mean.
(The sample mean is usually represented with a vertical bar as XBAR)

Question 14

Population variance

Answer 14

The variance of all observations in a population.
(The population variance is usually represented as σ
2)

Question 15

Sample variance

Answer 15

The variance of all observations in a sample. The sample variance is an
approximation of the population variance.
(The sample variance is usually represented as s^2)