D ATA A NALYSIS Histogram Second Generation Third Generation First Generation

Mean The arithmetic mean or average of a set of numbers is the expected value. The mean is calculated by adding up all the values, and then dividing that sum by the number of values. Median The median is the middle value in a set of values. To find the median, order the numbers from largest to smallest, and then choose the value in the middle. If you have a data set with an even number of values take the average of the two middle numbers.

Mode The mode of a set is the value or values that occur most frequently. There can be more than one mode in a set. If there is more than one mode, you simply list all of the modes. Range The range of a set of numbers is the maximum distance between any two values. In other words, it's the difference between the largest and smallest values.

Standard Deviation The standard deviation a way to measure how close together the elements are in a set of data. The standard deviation is the average distance between each data point and the mean. X = each value = mean N = number of values