Comparing the center and spread of data distributions

The  exercise appears under the 6th Grade Math Mission. This exercise uses numerical summaries and graphical displays to provide information about the center and spread of data.

Types of Problems
There are two types of problems in this exercise:


 * 1) Use the information to analyze the center and spread: This problem describes some summary statistics about two data sets. The student is asked to use the given information to compare the center and spread of the data sets described.Ctcasodd1.png
 * 2) Use the display to analyze the center and spread: This problem displays two data sets in a graphical display. The student is asked to use the displays to choose an appropriate description of the relationship between the center and spread of the displays.Ctcasodd2.png

Strategies
An ability to read statistical displays as well as a decent knowledge of statistical vocabulary are needed to ensure this exercise is done accurately and efficiently.
 * 1) Mean (average), median (middle) and mode (most) are the common description of center.
 * 2) In a display, the center is in the middle of the display but pulled in a direction of any skew.
 * 3) Standard deviation and IQR (Q3-Q1) are the common measures of spread.
 * 4) Data that is nicely patterned and close to each other (in heaps) tend to have smaller spread.

Real-life applications

 * 1) Dot plots, as most of statistics, can be found in everyday media to display information to consumers.