Chapter 2 Organizing Data

Section 2.1 Frequency Distributions, Histograms, and Related Topics

Do Now Using the chart on the board, place a tally mark in two spots: – The number of letters in your first name – The number of letters in your last name – Ex: My first name is Mark, so I’d put a tally mark at “4”. My last name is Frew, so I’d put an additional tally mark at “4”.

Histograms (Example) wit.com/gallery_histogram.html#histogram wit.com/gallery_histogram.html#histogram

Copy Figure 2-8 into Notebook Mound-shaped Symmetrical Typical Uniform Skewed Left Skewed Right Bimodal

Basic Steps for Creation by Hand Determine the Number of Classes Determine Class Width Determine Class Boundaries Tally Find Relative Frequencies Find Midpoints Graph (X axis = # Line, Y Axis = Freq or Rel. Freq)

Do Now Using the NFL Touchdown Data from 2011, complete the frequency distribution.

Steps in Excel: Be sure Data Analysis Toolpack is installed To Let Excel Decide on Bins: – Choose Data, Data Analysis, Histogram – Input Range is your data range. – Click Label if you have a title for your data. – Click Chart Output. – To make bars touch, click into white space on histogram:choose chart tools, design, chart layout #8 – Be sure to fix titles and labels

Steps in Excel: To have User Defined Bins: – Next to your data, type the right endpoint of each of your bars, with the exception of the last bar. – Choose Data, Data Analysis, Histogram – Input Range is your data range. – Bin Range is your right endpoints. – Click Label if you have a title for your data. – Click Chart Output.