Wednesday, September 9, 2009

CEDU 549 - Stats 2

Things to Remember:

* Two ways to figure out an average (mean) in Excel: =(B1+B2+B3)/3 or =average(B1:B3)

* A population consists of all members of some specified group. A parameter is a measure of a characteristic of an entire population.

* A sample is a subset of a population. It has the same characteristics as the population. A statistic is a measure of a characteristic of a sample.

* Scales of Measurement: Nominal (ex. social security#), Ordinal (in order - rank), Interval (IQ Scores), Ratio (ex. height and weight)

* Measures of Central Tendency: Mean, Median, Mode

* Measure of Variability: Range, Standard Deviation

* Negatively Skewed: tail points to the left, median is to the right of the mean, there are more higher scores

* Positively Skewed: tail points to the right, median is to the left of the mean, there are more lower scores

1 comment:

Jim said...

Cheryl,

How comforting to hear someone describe statistics as comforting!