bar graphs
Use a seperate and distinct bar for each piece of information
central tendency
statistic tells us what the sample as a whole, or on average, is like
correlation coefficient
is a statistic that describes how strongly variables are related to one another
descriptive statistics
allow researchers to make precise statements about data
effect size
a general term that refers to the strength of association between variables
frequency distribution
indicates the number of individuals that recurve each possible score on a variable
frequency polygons
use a line to represent frequencies
histograms
uses bars to display a frequency distribution for a quantitative variable
mean
the mean of a set of scores is obtained by adding all the scores and dividing by the number
median
the score that divides the group in half (with 50% scoringbelow and 50% scoring above the median).
mode
the most frequent score
multiple correlation
is used to combine a number of predictor variables to increase the accuracy of prediction of a given criterion or outcome variable
partial correlation
provides a way of statically controlling third variables
path analysis
a method used to develop models of possible relationships among a set of variables that were studied with the nonexperimental method
Pearson product-moment correlation coefficient
is used when both variables have interval or ratio scale properties
pie charts
divide a whole circle "pie" into "sclices" that represent relative precentages
regression equations
are calculations used to predict a person's score on one variable when that person's score on another variable is known
standard deviation
the average deviation of scores from the mean (the square root of the variance).
The mean is an appropriate indicator of central tendency only when scores are measured on an...... Why?
interval or ratio scale, because the actual values of the numbers are used in calcuating the statistic
The mode is the only measure of central tendency that is appropriate if what scale is used?
nominal scale
variability
a number that characterizes the amount of spread in a distribution of scores
variance
a measure of the variability of scores about a mean; the mean of the sum of squared deviations of scores from the group mean
What are four types of frequency distributions?
pie charts, bar graphs, frequency polygons, and histograms
What are pie charts particularly useful when representing what kind of data?
nominal scale information
What data is represented by frequency polygons?
interval or ratio scales
When is it appropriate to use the median scores? Why?
ordinal scale, because it takes into account only the rank order of the scores. Also useful with interval and ratio scale variables