8.3 Frequency Tables and Histograms

Frequency Table = Frequency Distribution lots of numerical data(quantitative) broken into 5 to 12 equal size categories(classes) counted up with tally marks

Frequency Distribution guidelines find the biggest value and the smallest value get the range = biggest - smallest calculate the width of each class divide the range by something manageable to get an answer between 5 and 12 build a table using the width for your classes on the left side tally it up to find your frequency

Model Class is the class with the most in it(highest frequency)

a bar graph for quantitative data the bars touch each other Histogram a bar graph for quantitative data the bars touch each other the x-axis is labeled using the midpoint of each class

Histogram guidelines Do the frequency table for the data Find the midpoint for each class class high + class low 2 Mark the bars equal width on the x-axis and touch Draw the bar as tall as its frequency

What’s the Difference between Bar Graph bars don’t touch bars represents one item or type can be qualitative or quantitative Histogram bars do touch bars represents a range of values can be quantitative only