Data TutorialData TutorialTutorial on Types of Graphs Used for Tutorial on Types of Graphs Used for

Data Analysis, Along with How to Data Analysis, Along with How to Enter Them in MS ExcelEnter Them in MS Excel

Carryn BellomoCarryn BellomoUniversity of Nevada, Las VegasUniversity of Nevada, Las Vegas

OverviewOverview

You will be given a brief description, example, You will be given a brief description, example, and “how to create” for each of the following:and “how to create” for each of the following: Bar GraphsBar Graphs Line GraphsLine Graphs Circle GraphsCircle Graphs ScatterplotsScatterplots Box and Whisker PlotsBox and Whisker Plots

OverviewOverview

Go to Go to http://www.unlv.edu/faculty/bellomohttp://www.unlv.edu/faculty/bellomoClick on the link for Click on the link for Teachers ForumTeachers ForumScroll down to Scroll down to Formula SheetsFormula Sheets, #7 (, #7 (How to graph…How to graph…))

For the Excel portion of the tutorial, please open the For the Excel portion of the tutorial, please open the file file Excel_Data.xlsExcel_Data.xls

Each Each tabtab on the bottom of the file corresponds to a on the bottom of the file corresponds to a data set, which is used to create the example.data set, which is used to create the example.

You can follow along to see how to use Excel to You can follow along to see how to use Excel to create each data plot.create each data plot.

Bar Graphs: IntroBar Graphs: Intro

Shows the frequencies of specific data values in Shows the frequencies of specific data values in a data set.a data set.

It can be used for categorical or numerical data.It can be used for categorical or numerical data. The length of the bar drawn for each data value The length of the bar drawn for each data value

represents the frequency of that value.represents the frequency of that value. Bars may be drawn vertically or horizontally.Bars may be drawn vertically or horizontally. To avoid confusion, the bars should be the same To avoid confusion, the bars should be the same

width.width.

Bar Graph: An ExampleBar Graph: An Example

Bar Graph: Creating in ExcelBar Graph: Creating in Excel Click on an empty cell.Click on an empty cell. Go to Go to InsertInsert, then , then ChartChart.. Make sure you have Make sure you have ColumnColumn highlighted, and press highlighted, and press NextNext.. Sometimes Excel tries to guess what you want, so you may see Sometimes Excel tries to guess what you want, so you may see

values in the values in the Data RangeData Range cells. If so, delete them. cells. If so, delete them. With the cursor in the With the cursor in the Data RangeData Range cells, click on the left most cells, click on the left most

value of your data table, and drag to highlight to the right most value of your data table, and drag to highlight to the right most data value.data value.

Click on Click on Next.Next. Title your graph, and label the vertical and horizontal axis.Title your graph, and label the vertical and horizontal axis. Then click on Then click on FinishFinish..

Line Graph: IntroLine Graph: Intro

Typically used for continuous data to show the change in a Typically used for continuous data to show the change in a variable (usually over time).variable (usually over time).

Each element of the sample is associated with an ordered Each element of the sample is associated with an ordered pair, with a independent variable (such as time) and a pair, with a independent variable (such as time) and a dependent variable.dependent variable.

The independent variable is marked on the horizontal axis, The independent variable is marked on the horizontal axis, and the dependent variable is marked on the vertical axis.and the dependent variable is marked on the vertical axis.

Each ordered pair is graphed, and are connected with line Each ordered pair is graphed, and are connected with line segments.segments.

Scaling is critical when trying to analyze the relationship Scaling is critical when trying to analyze the relationship between the variables.between the variables.

Line Graph: An ExampleLine Graph: An Example

Line Graph: Creating in ExcelLine Graph: Creating in Excel Click on an empty cell.Click on an empty cell. Go to Go to InsertInsert, then , then ChartChart.. Make sure you have Make sure you have LineLine highlighted, and choose your highlighted, and choose your

display type. Then press display type. Then press NextNext.. Again, if you see values in the Again, if you see values in the Data RangeData Range cells, delete them. cells, delete them. With the cursor in the With the cursor in the Data RangeData Range cells, click on the left most cells, click on the left most

value of your data table and drag to highlight to the right most value of your data table and drag to highlight to the right most data value.data value.

Click on Click on Next.Next. Title your graph, and label the vertical and horizontal axis.Title your graph, and label the vertical and horizontal axis. Then click on Then click on FinishFinish..

Circle Graph: IntroCircle Graph: Intro

Also called a pie chart.Also called a pie chart. Is a circle divided into parts (also called Is a circle divided into parts (also called

sections or wedges).sections or wedges). Each part shows the percent of the data Each part shows the percent of the data

elements that are categorized similarly.elements that are categorized similarly. The parts must sum to 100 percent.The parts must sum to 100 percent.

Circle Graph: An ExampleCircle Graph: An Example

Circle Graph: Creating in ExcelCircle Graph: Creating in Excel Click on an empty cell. Go to Click on an empty cell. Go to InsertInsert, then , then ChartChart.. Make sure you have Make sure you have PiePie highlighted, and choose your display highlighted, and choose your display

type. Then press type. Then press NextNext.. Again, if you see values in the Again, if you see values in the Data RangeData Range cells, delete them. cells, delete them. Go to the Go to the SeriesSeries tab, and click on tab, and click on Add. Add. With the cursor in the With the cursor in the ValuesValues box, enter the values in the box, enter the values in the

column titled “Percentage”.column titled “Percentage”. With the cursor in the With the cursor in the Category X axis labelsCategory X axis labels box, enter the box, enter the

values in the “Month” column.values in the “Month” column. Click on Click on Next.Next. Title your graph, then click on Title your graph, then click on FinishFinish..

Scatterplot: IntroScatterplot: Intro

Similar to a line graph, although the ordered Similar to a line graph, although the ordered pairs are not connected with line segments.pairs are not connected with line segments.

Each element of the data set has two different Each element of the data set has two different measurements.measurements.

The two coordinates of each point are The two coordinates of each point are determined by the two measurements for the determined by the two measurements for the corresponding element of the sample.corresponding element of the sample.

This is the best way to determine if two This is the best way to determine if two characteristics are related.characteristics are related.

Scatterplot: An ExampleScatterplot: An Example

Scatterplot: Creating in ExcelScatterplot: Creating in Excel Click on an empty cell. Go to Click on an empty cell. Go to InsertInsert, then , then ChartChart.. Make sure you have Make sure you have ScatterScatter highlighted, and choose your highlighted, and choose your

display type. Then press display type. Then press NextNext.. Again, if you see values in the Again, if you see values in the Data RangeData Range cells, delete them. cells, delete them. Go to the Go to the SeriesSeries tab, and click on tab, and click on Add. Add. With the cursor in the With the cursor in the X ValuesX Values box, enter the data values in box, enter the data values in

the column titled “Alcohol”.the column titled “Alcohol”. With the cursor in the With the cursor in the Y ValuesY Values box, enter the data values in box, enter the data values in

the “Tobacco” column.the “Tobacco” column. Click on Click on Next.Next. Title your graph, then click on Title your graph, then click on FinishFinish..

Scatterplot: The Best Fit LineScatterplot: The Best Fit Line

You can fit a linear equation to any scatterplot.You can fit a linear equation to any scatterplot. Once you have the data in a plot, right click on Once you have the data in a plot, right click on

any data point, and click on any data point, and click on Add TrendlineAdd Trendline.. Make sure Make sure LinearLinear is highlighted. is highlighted. Click on the Click on the OptionsOptions Tab, and check the box Tab, and check the box

titled “Display Equation on Chart”.titled “Display Equation on Chart”. Click Click OKOK.. The linear regression line will be added to your The linear regression line will be added to your

chart, along with the equation for that line.chart, along with the equation for that line.

Box and Whisker Plot: IntroBox and Whisker Plot: Intro

This is constructed with the “five-point This is constructed with the “five-point summary”.summary”.

The least and greatest values, median, and first The least and greatest values, median, and first and third quartiles are used to construct the and third quartiles are used to construct the box plot.box plot.

They are useful for comparing data sets.They are useful for comparing data sets.

Box & Whisker Plot: An Box & Whisker Plot: An ExampleExample

Box & Whisker: CreatingBox & Whisker: Creating

Click on an empty cell.Click on an empty cell. Find the necessary values by using excel functions Find the necessary values by using excel functions

(here, “DataRange” indicates the range of values (here, “DataRange” indicates the range of values where your data is, i.e. A1:A20)where your data is, i.e. A1:A20) Minimum: “=Min(DataRange)”Minimum: “=Min(DataRange)” Maximum: “=Max(DataRange)”Maximum: “=Max(DataRange)” Median: “=Median(DataRange)”Median: “=Median(DataRange)” 2525thth Percentile: “=Percentile(DataRange, 0.25)” Percentile: “=Percentile(DataRange, 0.25)” 7575thth Percentile: “=Percentile(DataRange, 0.75)” Percentile: “=Percentile(DataRange, 0.75)”

Next to these cells, enter a column of 1’sNext to these cells, enter a column of 1’s

Box & Whisker: CreatingBox & Whisker: Creating Go to Go to InsertInsert, then , then ChartChart.. Make sure you have Make sure you have ScatterScatter highlighted, and choose the highlighted, and choose the

display type without any connecting lines. Then press display type without any connecting lines. Then press NextNext.. If you see values in the If you see values in the Data RangeData Range cells, delete them. cells, delete them. Go to the Go to the SeriesSeries tab, and click on tab, and click on Add. Add. With the cursor in the With the cursor in the X ValuesX Values box, enter the data values box, enter the data values

you found earlier (min, max, etc.)you found earlier (min, max, etc.) With the cursor in the With the cursor in the Y ValuesY Values box, enter a column of 1’s. box, enter a column of 1’s. Click on Click on NextNext, title your graph, then click on , title your graph, then click on FinishFinish.. Delete the horizontal lines on your graph by clicking on one Delete the horizontal lines on your graph by clicking on one

of them and hitting the of them and hitting the DeleteDelete key. key. Delete the vertical axis by clicking on it and hitting the Delete the vertical axis by clicking on it and hitting the

DeleteDelete key. key.

Box & Whisker: CreatingBox & Whisker: Creating

Use the drawing toolbar to make the box and Use the drawing toolbar to make the box and whiskers (if you do not see the toolbar, click on whiskers (if you do not see the toolbar, click on ViewView ToolbarsToolbars Drawing).Drawing).

Put a line connecting the 1Put a line connecting the 1stst and 2 and 2ndnd points. points. Put a box connecting the 2Put a box connecting the 2ndnd and 4 and 4thth points (with points (with

the box highlighted, click on the small arrow the box highlighted, click on the small arrow next to and click next to and click No FillNo Fill to remove the fill to remove the fill color).color).

Put a vertical line through the 3Put a vertical line through the 3rdrd point. point. Put a line connecting the 4Put a line connecting the 4thth and 5 and 5thth point. point.

SummarySummary

We have gone over several types of graphs.We have gone over several types of graphs. Another data set can be found atAnother data set can be found at

http://http://www.unlv.edu/faculty/bellomowww.unlv.edu/faculty/bellomoClick on the link for Click on the link for Teachers ForumTeachers Forum

Practice by opening up the file called Practice by opening up the file called Excel_MoreData.xlsExcel_MoreData.xls and follow the directions and follow the directions in in redred..