September 20, 2010

# September 20, 2010 - Appendix B Statistical Methods...

This preview shows pages 1–2. Sign up to view the full content.

Appendix B: Statistical Methods Statistical Methods: Graphing Data -frequency distribution -histogram (basically a bar graph) -frequency polygon Descriptive Statistics: -measures of central tendency mean (average) median (middle) mode (most) -skewed distributions (when a distribution is symmetrical – it looks the same on both sides: mean median and mode are all in the same place [bell curve]_ negatively skewed (most data ends up lower of graph: more score is below the mean) positively skewed (most data ends up upper of graph: more score is above the mean) -measuring variability standard deviation **by no means does the mean tell you everything you need to know about the data** **check out calculating standard deviation** The Normal Distribution (Bell Curve): -Psychological tests relative measures standard deviation is the unit of measure **50 th percentile = 50% better than everyone else. 98 th percentile = 98% better than everyone else** Measuring Correlation: -Correlation coefficient positive = direct relationship **positive doesn’t mean good** - the more of one thing happens, the more of another thing happens negative = inverse relationship – if one goes up the other go down -Magnitude: 0 to plus/minus 1 (plus one = perfect positive relationship, zero = no relationship, minus one = perfect negative relationship) -Scatter diagrams -Correlation of determination Hypothesis Testing -inferential statistics -sample: has to represent the generalization of the population that you’re applying the

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 3

September 20, 2010 - Appendix B Statistical Methods...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online