Displaying Experimental Data
Scientists use tables and graphs to organize, present and summarize data collected during an experiment. Data presentation in table and graph format has two primary functions:
1. Analyze and interpret results
2. Enhance clarity of data for the reader
Table Guidelines
Tables are useful for:
1. Results that have only a few data points
2. Organizing observations
3. Displaying several dependent variables at the same time
· Tables are used to collect and record information during the experimental phase of research.
· When using a table in a report, the table is a summary of the data collected.
· Tables are numbered consecutively throughout the report.
· All tables must have a title, which is located at the top of the table. It should give enough information to allow the table to be understandable, apart from the text.
· The title goes above the table. Capitalize the first, last, and important words in the title. Do not capitalize articles (a, an, the), short prepositions, and conjunctions.
· Independent variable is in the left hand column with units of measurement. Units of measurement are typically abbreviated and in parentheses.
Table 1. Temperature of Boiling Water Measured over Five Minutes
Time (min) / Temperature (oC)0 / 99
1 / 100
2 / 100
3 / 100
4 / 99
5 / 98
Creating a Table in Word
· Open Word and on the top ribbon click on the Insert tab. There will be a table icon visible.
· Click the table icon below the insert tab. With your mouse drag the cursor and select the number of rows and columns needed for the table required.
· The table will be created and inserted when you click the last highlighted square of the table.
· You can change the format of your table by clicking Table Tools on the top ribbon. Click Layout to insert, delete or merge cells for example.
· Change the design of the table by clicking Design under Table Tools.
Graphing Guidelines
Graphs are used to:
1. Show relationships among independent and dependent variable
2. Provide a visual summary of results
3. Show trends. The effect the independent variable has on the dependent variable can be visualized more easily.
· Another name for graph is figure.
· Graphs should be accurately and clearly constructed, easily interpreted and well annotated.
· Use graph paper or a graphing program to plot values accurately.
· The intervals on the graph must be appropriate for the data being plotted so that most of the area on the graph is in use. In other words, avoid wasted space.
· The graph must have a title. The title is brief and contains the Independent and Dependent Variables. Capitalize the first, last, and important words in the title. Do not capitalize articles (a, an, the), short prepositions, and conjunctions.
· The independent variable goes on the x-axis along with the appropriate units of measurement (usually in parentheses and abbreviated).
· The dependent variable goes on the y-axis along with the appropriate units of measurement (usually in parentheses and abbreviated).
· Graphs are numbered consecutively throughout a report and are labeled as Figures with a brief statement directly below the figure. It serves a similar purpose as the title does in a table.
· If more than one set of data is being represented on a graph, use different colors or symbols. A key or legend must also be provided to indicate which is which.
Commonly used forms of graphs:
1. Line Graphs
2. Bar Graphs
Line Graphs
· Represent continuous data
· Used to represent continuous variables, those that have been unlimited number of values between points
· Emphasize rise and fall of the values over their range
· Plot data as separate points
· To show trends draw smooth curves or straight lives to fit the values plotted or connect the points dot to dot to emphasize meaningful changes in values on the x-axis
Figure 1. Boyle’s Law experimental data showing the relationship between
Pressure and volume.
Creating Line Graphs Using Excel:
1. Collect data from your experiment. Open the excel program.
2. Determine which value is the INDEPENDENT variable and which is the DEPENDENT variable. The independent variable goes on the x-axis. The dependent variable goes on the y-axis.
3. Start Excel by clicking the icon on the desktop or by selecting Microsoft Excel from the Start menu by clicking Start ® Programs ® Microsoft Excel.
4. Enter the independent values in column A.
5. Enter the dependent values in column B.
6. Select the data by holding down the left mouse button as you drag from cell A1 to the last data entry in column B. The data in both columns should be selected.
7. Click Insert, under Charts select Scatter, and then select the first item shown.
8. On the Layout tab at the top, select Axis Titles to label the X- and Y-axes. Select Chart Title to give the chart a title. These options will enable you to enter the names directly on the chart.
9. You can save the chart by copying it into a Word document and then saving the Word document. To copy the chart, click the chart and press Control-C. To paste it into a Word document, open Word, place the cursor where you want the chart and press Control-V.
To see a visual of how to create a basic line graph go to http://screencast.com/t/k8ShYsTSA
You may or may not need to place a best fit line. If you do:
10. To insert a best fit line, on the Layout tab, go to Analysis, click Trendline, and then choose Linear.
Bar Graphs
· Vertical bars are used. Used for data that represents separate and discrete groupings or categories. Emphasizes the discrete differences between the groups. Data belongs to one or the other group.
· Must use different colors (or lines) AND provide a key or legend to indicate which group is which.
Figure 2. Differences in bounce height of various balls each
dropped from a release height of one hundred centimeters.
Creating Bar Graphs using Excel:
1. Collect data from your experiment. Open the excel program.
2. Determine which value is the INDEPENDENT variable and which is the DEPENDENT variable. The independent variable goes on the x-axis. The dependent variable goes on the y-axis.
3. Start Excel by clicking the icon on the desktop or by selecting Microsoft Excel from the Start menu by clicking Start ® Programs ® Microsoft Excel.
4. Enter the bar (category) names (X-Axis) in column A.
5. Enter the value of each bar (category) in column B.
6. Select the data by holding down the left mouse button as you drag from cell A1 to the last data entry in column B. The data in both columns should be selected.
7. Click Insert, under Charts select Column, and then select the first item shown under 2-D Column.
8. On the Layout tab at the top, select Axis Titles to label the X- and Y-axes. Select Chart Title to give the chart a title. These options will enable you to enter the names directly on the chart.
9. You can save the chart by copying it into a Word document and then saving the Word document. To copy the chart, click the chart and press Control-C. To paste it into a Word document, open Word, place the cursor where you want the chart and press Control-V.
To see a visual of how to create a basic bar graph go to: http://screencast.com/t/OMvaf5vLHNT
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