7.3 Measures of Central Tendency and Dispersion

Mean – the arithmetic average is the sum of all values in the data set divided by the number of values. Median – the middle value when the data values are arranged in ascending or descending order. If there are an even # of values then find the mean of the middle 2 values. Mode – the value that is repeated most often from the data. Can be 0, 1 or more than one modes Measures of Central Tendency

Measures of Dispersion Standard Deviation : Symbol Range : highest value – lowest value How Spread Out sigma Formula

normal curve When we talk about data, often times it falls on what we call a normal curve.

Standard Deviation This gives us a picture of how the Standard Deviation can tell us how an individual value relates to the bulk of the data.

Find the, median, mode and range for the following data. 40, 45, 39, 40, 42, 41, 37, 41, 40, 41

40, 45, 39, 40, 42, 41, 37, 41, 40, 41 Now let’s find the standard deviation.