Measures of Center with Example

If we take a sample of the first three data values we have {1880, 160, 1500} we can manually find the mean easily. Add all the sample values together. Divide by the number of values. Then the sample mean is _ _.

Is this mean a parameter or a statistic?

GeoGebra Graphing and most graphing calculators allow this to be done in one step. Mean( ) Because our data is labeled Feet we use Mean(Feet). Find the mean distance ran by the forty children.

Is this mean a parameter or a statistic?

Mode is the value that occurs most frequently. If we sort the data that will help us find value that occurs most frequently. Looking at the dot plot, what is the mode distance these children ran?

Find the exact answer using the Mode( <data> ) function.

Is this mode a parameter or a statistic?

We can find the median by first sorting the data. Sort(Feet) = {160, 420, 440, 480, 520, 560, 580, 640, 660, 660, 680, 740, 740, 760, 760, 820, 820, 940, 1100, 1120, 1140, 1160, 1200, 1240, 1260, 1260, 1320, 1340, 1360, 1500, 1500, 1500, 1540, 1620, 1760, 1880, 1940, 2000, 2180, 2960} Then finding the value in the middle. Because 40 is even there will be two values. What are the two middle values?

We take the average (mean) of these two values to find the median. So, the median distance these forty children ran was _ _.

Is this median a parameter or a statistic?

We can also use GeoGebra function Median( <data> ) What is the median distance run by the children using technology?

If we were studying the endurance of children in USA, then what is the population and sample?

For a sample of number { 1, 2, 3, 4, 4} find the three measures of center.

For a sample of colors { green, green, white, yellow, yellow } find the center.