Statistics, Day 1

Tuesday, February 16th

We reviewed the concepts of central tendency: mean, median, and mode. The mean is the average of the values in a data set. The median is the middle number of the values in the data set when it is arranged in numerical order. The mode is the value that occurs the most often. These concepts were taught to the students in previous math courses. However, we now want them to be able to pick one (or more) of those values that best represents the data. Students should consider whether or not outliers move the mean further up or down away from the center. They should also consider if having a dense group of numbers positions the median further away from part of the data values.

We also reviewed the concepts of a frequency table and a histogram. Both of these can have the data values grouped together or listed individually. They should have between 5 and 10 spans or individual data values. A frequence table lists the data values or spans of the data values in one column and then records the number of times those values occur in the data. A histogram shows the data values or spans of the data values on the x-axis and then has bars going up with a height equal to the frequency for that value. A histogram is a bar graph, however it is slightly more specific: it must have a continuous set of numbers on the x-axis. (A bar graph can have words recorded along the horizontal axis.)

Homework: Histogram Worksheet and Page 365, #1 - 8, 15 b & c, 16, and 17 a & b.

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