Unit 0: Statistics Flashcards
Measures of Central Tendency
describe the middle of the data; include mean (average), median (middle score), more (most frequently occurring score)
Regression to Mean
if an initial score or results is an outlier, the following scores will most likely be closer to average
Outliers
extreme scores (they often distort mean)
Normal. (Symmetrical) Distribution (Bell Curve)
a group of scores for which the mean, median and mode are the same and half of the data is on either side of the mean
Skewed Distribution
a group of scores for which mean, median, and mode are different, caused by outliers pulling the mean away from the center of the data.
Bimodal Distributions
distributions with 2 peaks with a valley between (ie, traffic in front of the school based on time of day)
Measures of Variability
describe how different data points are from each other ; includes range, variance, standard deviation, percentiles
Standard Deviation (SD)
how far away a score is from the mean. Sign (+/-) indicates direction from mean
Scatter Plots
graphs used to show positive and negative correlations
Correlation Coefficient
a statistical measure of the extent to which two factors relate to each other
Statistical Significance
if the difference between the control and experimental groups is large enough, it is most likely not due to chance (a fluke) and we can say that the difference was caused by the IC and the results are statistically significant
Effect Size
tells you how meaningful the relationship between variables or the difference between groups is. It indicates the practical significance of a research outcome. A large effect size means that a research finding has practical significance, while a small effect size indicates limited practical applications
