Finding the Center of Data Sets: Mean and Median

This lesson covers how to find the center of data sets using mean and median. It explains the calculation of mean by summing all data points and dividing by the number of points, and median as the middle value in ordered data. The lesson introduces the mathematical formula for mean and discusses when to use mean versus median, highlighting the impact of outliers. Practical examples illustrate these concepts, emphasizing that mean is affected by extreme values, while median is more robust in skewed data.

What is the mean of a data set?

• The sum of all data points divided by the number of points

• The highest value in the data set

• The middle value when data is ordered

• The most frequently occurring value

How is the median determined in an odd-numbered data set?

• By averaging the two middle values

• By selecting the highest value

• By selecting the middle value

• By averaging all values

What does the symbol 'sigma' represent in the mean formula?

• The median of the data set

• The sum of the data points

• The mean of the data set

• The number of data points

Why might the median be preferred over the mean in certain data sets?

• Because it uses all data points

• Because it is easier to calculate

• Because it is unaffected by outliers

• Because it is always larger

How do outliers affect the mean?

• They have no effect

• They make the mean smaller

• They pull the mean towards the outlier

• They make the mean equal to the median

In a symmetric data set with no outliers, which measure of center is typically used?

• Median

• Mode

• Mean

• Range

What is the most appropriate measure of center for a data set with an outlier?

• Mode

• Range

• Median

• Mean