Statistics Flashcards
Central tendency
Attempt to mark the center of a distribution
Mean
The average of all the scores in a distribution
Median
The central score in the distribution
Mode
The score that appears most frequently
Bimodal
When a distribution has more than one mode. This is when two scores equally frequently and more frequently than any other score
Positively skewed
When a distribution includes an extreme score that is very high
Negatively skewed
When a distribution includes an extreme score that is very low
Range
The distance between the highest and lowest scores in a distribution
Variance
The standard deviation squared
Standard deviation
The square root of the variance
Normal curve
A theoretical bell-shaped curve for which the area under the curve lying between any two z-scores has been predetermined
Percentiles
Indicated the distance of a score from 0
Correlation
Measures the relationship between two variables
Correlation coefficient
A statistic that computes the strength of a correlation
Scatterplot
The graph of a correlation
Statistically significant
When the probability value is less than 0.05 or 5%
Effect size
Practical significance or how large the effect is
Replication
When a study is conducted again using the same methodology in an attempt to see if the results will be the same
Meta-analysis
Type of research that combines the results of many studies on the same topic in order to approximate an average effect
Peer review
A process by which a paper is read by several others in the field and the author is asked to make revisions in order to ensure high quality publications
No coercion
Participation should be voluntary
Informed consent
Participants must know that they are involved in research and give their consent
Deception
It is ethically preferable to keep deception to a minimum
Informed assent
Minors should be asked to assent and may also be asked to obtain the consent of their parent or guardian
