PSY 210 Quiz 1

quantity calculated from a population

quantity calculated from a sample

Sigma: Population Standard Deviation

Symbol for population deviation

Sigma Squared: Population Variance

Population Variance

mu: population mean

population mean

variance of the population - usually estimated, rarely computed

Set of all objects that we're interested in researching

square root of the variance

Subset of the population; set of the actual observations

results are unlikely to have occured by chance alone

each member of the population has an equal chance of being included

sample mean

Sample Variance

Sample Standard Deviation

Individual Observation; Raw Score

Given a population with finite mean mu and finite variance sigma squared, the sampling distribution of the mean approaches a normal distribution with the mean mu and variance sigma squared divided by N, as N, the sample size, increases

Mean

Median

Mode

arithmatic average: The sum of the scores divided by the number of scores

Middlemost score

the most frequently occuring score

x axis; horizontal axis

y axis; vertical axis

bar chart

the number of observations

Bell Curve; Mesokurtic

Frequency Polygon

a skewed bell curve; a measure of the degree to which a distribution is asymmetrical

levelness/flatness around the mode of a frequency distribution

more scores in the tails and fewer in the middle as compared to the corresponding normal distribution

most commom with small sample sizes 

more scores in the middle and fewer scores in the tails as compared to the normal corresponding distribution

Bimodal

Leptokurtic Distribution

Uniform Distribution

Range

Variance

Standard Deviation 

Largest score minus the smallest score

average of the square deviations from the mean

Standard Normal Distribution