Range and Outliers

Range The positive difference between the largest and smallest values in a data set Example #1 The data set is 7, 10, 4, 6, 7, 8, 3 The high value is 10 The low value is 3 The range is 10-3 = 7

Outlier A value that is much smaller or larger than the other data values A data set may have one or more outliers or no outliers at all Outliers can affect all measures of central tendency – mean, median, mode When a small set of data has an outlier, the mean is usually affected more by an outlier than the median is affected Some outliers are just as important as the other data values, while others are best removed from the data set

Outliers (cont) In this data set, 5 could be considered an outlier. However, this piece of data is important and just represents an off day for the number of baskets scored in a game. It doesn’t represent a mistake and therefore, shouldn’t be removed!

Outliers (cont) In this data set, 31 can be considered an outlier. In this case, it is likely a mistake in measurement or recording. It should be removed from the data set.

Bookwork Grade 7 textbook Page 437 # 4, 6, 8, 10, 12, 14 Page 444 # 3, 5, 7 Page 450 # 4, 5, 7, 9