Chapter 3 Flashcards
Bimodal Distribution
When you have 2 modes in a distribution
Correlation
Tell us the relationship between two variables, there are 3 types: positive, negative, and zero
Correlation Coefficient
When describing the relationship between any 2 variables, this is what you determine
Descriptive Statistics
Summarize and describe data
Frequency Distribution
Expresses how often a score occurs in a set of data
Interval Scale of Measurement
One in which equal differences in scores represent equal differences in amount of the property measured, but with an arbitrary zero point
Mean
Mathematical average of the distribution of scores
Measures of Central Tendency
Mean, median, mode
Median
The middle score in a distribution
Mode
The most frequently occurring score in a distribution
Multimodal Distribution
If you have 3 or more modes in your distribution
Negative Correlation
When a high score on one is accompanied by a low score on the other
Negatively Skewed Distribution
More of the scores fall above the mean
Nominal Scale of Measurement
The data are “categorical”
Normal Curve
A graphical representation of a normal distribution (bell curve)
Normal Distribution
An arrangement of a data set in which most values cluster in the middle of the range and the rest taper off symmetrically toward either extreme
Ordinal Scale of Measurement
Involves the rank order system, a scale in which scores indicate only relative amounts or rank order
Positive Correlation
When a high score on one is accompanied by a high score on the other
Positively Skewed Distribution
More of the scores fall below the mean
Range
The difference between the high score and the low score in the distribution
Ratio Scale of Measurement
Has all the properties of an interval scale with the additional property of zero indicating a total absence of the quality being measured
Skewed Distribution
One in which the majority of scores fall at either the high end or the low end rather than the middle of a distribution
Standard Deviation
The spread of scores around the mean
Variance
A statistical concept that tells you the spread of scores within a distribution
Zero Correlation
There is no relationship between the variables
What are the three measures of central tendency?
Mean, Median, Mode
What are the measures of variance?
Standard deviation
What is/are the mode(s) in this data set: 25, 44, 45, 45, 56, 79, 83
45
What is/are the mode(s) in this data set: 25, 44, 44, 45, 56, 79, 79, 83
44, 79
What is the median in this data set: 25, 44, 45, 56, 79
45
What is the median in this data set: 25, 44, 45, 56
44.5
What is the mean of this data set: 25, 44, 45, 45, 56, 79
49
What is the range of the data set in #7? (above)
54
