1. Displaying Data:  Dot Plots  Grouped Frequency Tables  Histograms Slide 10.1- 1

2. Slide 10.1- 2 Graphs are used to try to tell a story.

3. Slide 10.1- 3 A dot plot, or line plot, provides a quick and simple way of organizing numerical data. They are typically used when there is only one group of data with fewer than 50 values. Dot Plots

4. Slide 10.1- 4 Suppose the 30 students in Abel’s class received the following test scores: Dot Plots

5. Slide 10.1- 5 A dot plot for the class scores consists of a horizontal number line on which each score is denoted by a dot, or an x, above the corresponding number-line value. The number of x’s above each score indicates how many times each score occurred. Dot Plots

6. Slide 10.1- 6 The score 52 is an outlier Scores 97 and 98 form a cluster A gap occurs between scores 88 and 97. Dot plots Two students scored 72. Four students scored 82.

7. Slide 10.1- 7 Outlier a data point whose value is significantly greater than or less than other values Clusteran isolated group of points Gap a large space between data points Mode data value(s) that occur most often. Dot Plots

8. Slide 10.1- 8

9. Slide 10.1- 9 Frequency Tables Ages of Presidents at Death

10. Slide 10.1- 10 Frequency Tables A grouped frequency table shows how many times data occurs in a range. The data for the ages of the presidents at death are summarized in the table.

11. Slide 10.1- 11  Each interval has the same size.  We know how many data values occur within a particular interval but we do not know the particular data values themselves. Frequency Tables Characteristics of Frequency Tables

12. Slide 10.1- 12 Histograms A histogram is made up of adjoining rectangles, or bars. The bars are all the same width. The scale on the vertical axis must be uniform.

13. Slide 10.1- 13 Uniform scale Histograms The death ages are shown on the horizontal axis and the numbers along the vertical axis give the scale for the frequency. Frequencies are shown by the heights of vertical bars each having same width.