Associated Learning Objectives:
- Create and interpret histograms
A histogram chart can only be constructed using an actual data set. To create a histogram from a frequency distribution, first you must create a data set with that frequency distribution.
Create a data set from a frequency distribution:
- Paste the frequency distribution into cell A1 of Google Sheets so the values are in column A and the frequencies are in column B.
- Enter 1 into cell C2 and enter the formula "=INDEX($a$2:$a$#,C2)" into cell D2, where # is the row number of the final row of the frequency distribution. The formula in column D will pick values from the value list based on the values in the index column.
- Enter the formula "=IF(COUNTIF($D$2:D2,D2)=INDEX($B$2:$B$6,C2),C2+1,C2)" into cell C3. This formula determines the index of the next value. "COUNTIF($D$2:D2,D2)" counts the number of times the last value in column D occurs. “INDEX($B$2:$B$6,C2)” gives the number of times that value should occur. If the two are equal, then the index is increased by 1. Otherwise, more of that value is needed, so the index is not changed.
- Copy and paste the formula from D2 into cell D3.
- Select cells C3 and D3 and use the fill down feature to copy the formulas until all the values are listed in column D.
Create a histogram from a data set:
- Select all of the data in column D, click the Insert menu option, and select Chart… to create a chart from the selected data. Google Sheets will automatically choose a chart it thi
- ks will display the data properly; if this is not a histogram, open the “Chart type” drop-down menu in the DATA tab of the Chart editor and select the Histogram option.
- Use the CUSTOMIZE tab of the Chart editor to change the horizontal axis as desired. The minimum and maximum values can be changed in the Horizontal Axis sub-tab, and the class width can be changed with the “bucket size” option in the Histogram sub-tab. (Note that you cannot open both sub-tabs at the same time as seemingly shown in the image below; the image has been edited to show both for instructional purposes.)