Chapter 3: STAT Book

Statistic: Is a characteristic or measure obtained by using the data values from a sample.

Parameter: Is a characteristic or measure obtained by using all the data values from a specific population.

Mean: Is the sum of the values, divided by the total number of values.

In statistics, Greek letters are used to denote parameters, and Roman letters are used to denote statistics.

Measures of Central Tendency: Mean, Median, Mode, Midrange.

Measures of Variation: Range, Variance, and Standard Deviation.

Measures of Position: Percentiles, Deciles, and Quartiles.

Median: Is the midpoint of the data array.

Mode: The value that occurs most often in a data set.

Midrange: Is defined as the sum of the lowest and highest values in the data set divided by 2.

Weighted Mean: Is a type of mean that considers an additional factor.

Range: Is the highest value minus the lowest value.

The Population Variance: Is the average of the squares of the distance each value is from the mean.

The Population Standard Deviation: Is the square root of the variance.

Coefficient of Variation: Is the standard deviation divided by the mean.

A z-score or Standard score: Is obtained by subtracting the mean from the value and dividing the result by standard deviation.