31 terms

PSY3213C Test 3, FSU, Chapters 9, 10, & 11

a branch of mathematics that involves the collection, analysis, and organization of data
descriptive statistics
procedures used to summarize data
inferential statistics
procedures used to analyze data after an experiment is completed in order to determine whether the IV had a significant effect
the assignment of symbols to events according to a set of rules
scale of measurement
a set of measurement rules
nominal scale
a scale in which the events are assigned to categories (i.e. left-handed vs right-handed)
ordinal scale
a scale that permits events to be rank ordered without necessarily having equal distance between points
interval scale
a scale that permits rank ordering with the assumption of equal intervals between adjacent events (no true zero)
ratio scale
a scale of measurement that permits rank ordering, equal distance, and a true zero point
the score that occurs most often
the number that divides a distribution in half
the mathematical average
pie chart
graphical representation of the percentage allocated to each alternative as a slice of a circular pie
A graph of vertical bars representing the frequency distribution of a set of data, the bars touch, generally intervals
bar graph
a graph in which the frequency of each category of a qualitative variable is represented as a vertical column, bars do not touch.
frequency polygon
type of line graph that shows frequency distributions; made by placing a dot on each bar of a histogram, connecting the dots, and removing the bars
line graph
a graph that uses line segments to show how data changes
vertical or y-axis of a graph
horizontal or x-axis of a graph
the extent to which scores are spread out around the mean
a measure of variability that is computed by subtracting the smallest score from the largest score
a single number that represents the total amount of variation in a distribution, also the square of the standard deviation
standard deviation
square root of the variance, has important relations to the normal curve
normal distribution
a symmetrical, bell-shaped distribution having half the scores above the mean and half the scores below the mean (bell curve)
correlation coefficient
a single number representing the degree of relation between two variables
null hypothesis
the claim that the relationship proposed between two variables does not exist, or that the difference in data was due to chance (not the operation of the IV)
t test
an inferential statistical test used to evaluate the difference between two means
degrees of freedom
the ability of a number in a specified set to assume any value
type I error
accepting the experimental hypothesis when the null hypothesis is true
type II error
accepting the null hypothesis when the experimental hypothesis is true
effect size
the magnitude or size of the experimental treatment