QMS 102 Lecture Notes - Lecture 3: Cumulative Frequency Analysis, Royal Institute Of Technology, Quartile

• School: Ryerson University
• Department: Quantitative Methods
• Course: QMS 102
• Professor: Nursel Ruzgar

Document Summary

Visualizing numerical data: the ogive (cumulative % polygon) Start with a frequency distribution table and add a cumulative frequency column and a cumulative relative frequency column. You may construct two kinds of cumulative relative frequencies. Both kinds of cumulative frequency will give you the same answer. However, it is more common to use c% to construct the ogive: cumulative relative frequency (crf) crf= relative frequency (rf) of the class + sum of all previous class relative frequencies. Alternatively, crf=sum of all relative frequencies up to and including the class. Step 2: draw the ogive: to plot the ogive, you need to construct the vertical axis (y-axis) representing the c% and the horizontal axis (x-axis) representing the upper boundary for each class intervals. In this section, you will learn to estimate percentiles using an ogive. A percentile is the value below which a certain percent of observations fall.