Lect4 - Frequency and Relative Frequency Tables Bar Charts...

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Frequency and Relative Frequency Tables Outline Frequency and Relative Frequency Tables Bar Charts and Pie Charts Mode and Median Xinghua Zheng Categorical Data Description
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Frequency and Relative Frequency Tables Example 1. Amazon Hosts ± Every day, more than 100 million shoppers visit Amazon.com, either by typing the address into their browser or by clicking through from another web site (host). ± Motivating Question: Which hosts send the most visitors to Amazon’s website? (So that Amazon can further decide whether it’s worthwhile to pay more to keep links on certain busy sites.) Xinghua Zheng Categorical Data Description
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Frequency and Relative Frequency Tables Looking At Data Date Purchase Amount ($) Host Region 21Sep2002 No 0 yahoo.com Northeast 21Sep2002 Yes 65.97 msn.com West 21Sep2002 10.00 google.com South 22Sep2002 No 0 Midwest 22Sep2002 25.10 yahoo.com Northeast 22Sep2002 125.08 Midwest . . . . . . . . . . . . . . . 1 I Data set consists of 188,996 visits I To answer the motivating question we must describe the distribution of Hosts ± Host is a categorical variable 1 The Host field is left blank when the customer typed amazon.com into a browser. Xinghua Zheng Categorical Data Description
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Frequency and Relative Frequency Tables Frequency and Relative Frequency Tables ± For categorical data, names identify different categories I This data can be summarized using a frequency table ± A table that summarizes the number of items (i.e., frequency) in each of several non-overlapping classes or a relative frequency table ± A table that summarizes the proportion of items in each class ± For each class, proportion =relative freqency= the frequency of the class divided by the total number of observations Xinghua Zheng Categorical Data Description
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Frequency and Relative Frequency Tables Frequency and Relative Frequency Tables Xinghua Zheng Categorical Data Description
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This note was uploaded on 12/28/2010 for the course ISOM ISOM111 taught by Professor Anthonychan during the Fall '09 term at HKUST.

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Lect4 - Frequency and Relative Frequency Tables Bar Charts...

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