PSY 120 Lecture Notes - Lecture 2: Intellectual Disability, Statistical Significance, Blind Experiment
Document Summary
Measuring correlations: correlation coefficient, statistical measure of correlation (ranges -1. 00 to +1. 00) Indicates size and direction of correlation: often graphed using scatter plots. Cautions about correlations: correlations are often reported but may be small, nonexistent, or meaningless, correlations may be misleading, correlations do not establish causation. Independent variable (iv)- manipulated or controlled by the experimenter: dependent variable (dv)- what the scientist is measuring. Evaluating the findings: once data is collected, psychologists evaluate results in 3 ways, describe them, assess how reliable and meaningful they are, figure out how to explain them. Descriptive statistics: statistical procedures that organize and summarize research data (ex: graphs and charts, use arithmetic mean and standard deviation. Inferential statistics: statistical procedures that allow researchers to draw inferences about how statistically (cid:373)ea(cid:374)i(cid:374)gful a stud(cid:455)"s results are, most common are significance tests. Indicate how likely a result occurred by chance: when likelihood is low, result is said to have statistical significance.
