Presentation on theme: "Frequency Polygons and Ogives"— Presentation transcript:
1 Frequency Polygons and Ogives Chapter 2.2Frequency Polygons and Ogives
2 The frequency polygonThe frequency polygon is a graph that displays the data by using lines that connect point plotted for the frequencies at the midpoints of the classes. The frequencies are represented by the heights of the points
3 Record High Temperatures for Each State Class LimitsClass boundariesClass MidpointFrequency28181371
4 Steps for creating a frequency polygon Find the midpoints of each class.Draw and label the x and y axes. Label the x- axis with the midpoints of each class, the y- axis as frequencyPlot the points, x values = midpoints, y values = frequencyConnect adjacent point with line segments. Connect to x-axis at beginning and end of graph
8 OgiveThe ogive is a graph that represents the cumulative frequencies for the classes in a frequency distribution.
9 Steps for creating an Ogive Find the cumulative frequency for each classDraw the x and y axes. Label x-axis with class boundaries, y-axis cumulative frequenciesPlot the cumulative frequencyConnect adjacent points with line segments
10 Cumulative Frequency for MPG of SUVs Cumulative Frequency less than 11.5 less than 12.5 less than 13.5 less than 14.5 less than 15.5 less than 16.5 less than 17.5 less than 18.5 less than 19.5: