Handling Data – Cumulative Frequency and Step Polygons Key topics : Cumulative Frequency Upper boundary, Discrete Data Continuous Data

Handling Data – Cumulative Frequency and Step Polygons Types of graphs covered : 1.Cumulative Frequency Step Polygons 2.Cumulative Frequency Polygons 3.Cumulative Frequency Curves

Cumulative Frequency and Step Polygons What is cumulative frequency?

Cumulative Frequency and Step Polygons What is cumulative frequency? This is where we calculate a running total of the frequencies

Cumulative Frequency Number of People in a Household FrequencyCumulative Frequency = = = = = = = 30

Cumulative Frequency No of letters in a crossword solution Frequency By adding an extra column to this table, calculate the cumulative frequencies for this data.

Cumulative Frequency No of letters in a crossword solution FrequencyCumulative Frequency

Cumulative Frequency Step Polygons No of letters in a crossword solution FrequencyCumulative Frequency Drawing a cumulative frequency step polygon for this data.

Cumulative Frequency Step Polygons No of letters in a crossword solution Frequenc y Cumulative Frequency

Cumulative Frequency Step Polygons No of letters in a crossword solution FrequencyCumulative Frequency Plot points at upper boundary of each class

Cumulative Frequency Step Polygons No of letters in a crossword solution FrequencyCumulative Frequency Joins points to create steps

Cumulative Frequency Step Polygons No of letters in a crossword solution FrequencyCumulative Frequency

Cumulative Frequency Polygons This graph is similar to the cumulative step polygons. Cumulative frequencies as a running total are calculated in the same way. Birth Weight (kg) Frequency What sort of data is this?

Cumulative Frequency Polygons This data is continuous. Birth Weight (kg) Frequency Cumulative Frequency How would we draw the graph? What would the axes look like? Where would you plot the points?

Cumulative Frequency Polygons Birth Weight (kg) Frequency Cumulative Frequency Plot points at upper boundary of each class

Cumulative Frequency Polygons Birth Weight (kg) Frequency Cumulativ e Frequency Plot points at upper boundary of each class

Cumulative Frequency Polygons Birth Weight (kg) Frequency Cumulative Frequency Join points with straight lines. Start at lower bound of first class with cumulative frequency of 0.

Cumulative Frequency Polygons Birth Weight (kg) Frequency Cumulative Frequency Don’t forget to give graph a title.