Central Tendency

Question 1

Mean

Answer 1

Average

a1+a2+a3/n

Question 2

The mean is deeply affected by?

Answer 2

Outliers

Question 3

Median

Answer 3

The exact middle value

Question 4

The median is unaffected by

Answer 4

Outliers

Question 5

Arithmetic Mean

Answer 5

The sum of scores divided by number of scores N; computation for sample and population

Question 6

Bell curve (gaussian distro)

Answer 6

The theoretical shape of the standard normal distribution: mean median mode are centered, roughly 50% of scores on either side

Question 7

Bimodal distribution

Answer 7

A distribution with two modes

Question 8

Bimodal distribution

Answer 8

A distribution with two modes

Question 9

Central Tendency

Answer 9

The mean (average), the median (middle value), and mode (value occuring most frequently); descriptive statistics that tend to be near the center of a distro.

Question 10

Median

Answer 10

the middle value of a score distro; not affected by outliers; n+1/2
for odd n, put scores in order and find middle. For even, put scores in order and calculate average of two middle values

Question 11

Modal distro

Answer 11

A distribution described by the mode of the data

Question 12

Unimodal Distribution

Answer 12

Distributions with a single mode

Question 13

Bimodal distributions

Answer 13

Distros with two modes: usually from combined data sets

Question 14

multimodal distribution

Answer 14

A distribution showing more than one mode

Question 15

Population mean

Answer 15

The sum of all the scores in a population divided by the number of scores in that population

Question 16

Population size (N)

Answer 16

The number of instances/individual scores of everything you want to study

Question 17

Positively Skewed

Answer 17

A distribution where the mean is greater than the mode

Question 18

Negatively Skewed

Answer 18

a distro where the mean is less than the mode

Question 19

Nonmodal distributions

Answer 19

distributions where each score is the same, the distribution being a straight line

Question 20

Sample mean

Answer 20

The mean of a sample, sum of each value divided by n

Question 21

sample size (n)

Answer 21

the number of instances or measurements in a sample

Question 22

unimodal distribution

Answer 22

A distribution, like the normal distro or a basic skewed distro, with one value occurring more often

Question 23

Weighted mean

Answer 23

Used when 2+ sample sizes (n) are uneven. Sum the products of the mean and sample size for each sample, then divide by the total sample size. Higher than arithmetic mean.