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* Positive Correlation: Defined by Timothy C. Urdan as: "A characteristic of a correlation; when the scores on the two correlated variables move in the same direction, on average. As the scores on one variable rise, scores on the other variable rise, and vice versa." (For more, see Urdan, T.C. (2005) Statistics in Plain English (2nd edition). Lawrence Erlbaum Associates, Inc.)
Note: Positive/negative correlations are found through "Correlational Analysis," which measures the strength of an association between two variables. Values range from +1.00 to –1.00.
Rule of Thumb: Correlation should NEVER be confused with causation = they are very different things, and involve a very different set of calculations and often different research designs (methods, analysis, control groups, etc.). Causation causes correlation, but it is not necessarily the other way around. It is much easier to establish correlation than causation. And it is also very easy to confuse or inflate the significance of correlation - as seen in the media effects debates discussed in next week's Kline reading.