A correlation can range in value from −1.00 to +1.00. The absolute value of the coefficient reflects the strength of the correlation. So a correlation of −.70 is stronger than a correlation of +.50. One frequently made mistake regarding correlation coefficients occurs when students assume that a direct or positive correlation is always stronger (i.e., “better”) than an indirect or negative correlation because of the sign and nothing else. To calculate a correlation, you need exactly two variables and at least two people. Another easy mistake is to assign a value judgment to the sign of the
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