Data Presentation is not a mystery!

1. Data Presentation is not a mystery! • Graphs • Tables

2. An Experiment • The hypothesis is pea plants sprayed with gibberellic acid will be taller because of greater internode elongation. • The control plants are sprayed with distilled water and the experimental plants sprayed with a dilute solution of gibberellic acid. There are 10 plants per treatment. • Plant heights are measured for 5 days in row on the fifth day the number of leaves and the second internode from the apex is measured. • What follows is how the data will be presented.

3. Graph construction • You have height data over time for control and treatment pots. • Each pot consisted of several plants. • Each day after spraying you measured plant height. • Plot the average height of all of your plants in the control pots versus time. • Plot the average height of all of your plants in the treatment pots versus time. • Put both plots on the same piece of graph paper.

4. Graph Basics • Graphs always have axes. • Graphs always use the whole piece of graph paper. • Graphs always have titles and are numbered • Graphs always have axes titles • Graphs always have units given in the axes titles • A graph always have appropriate tick marks • A graph can have a legend

5. Graphs always have axes.

6. Graphs always use the whole piece of graph paper!!

7. A graph always has a title and are numbered. Figure 1. The Effect of Gibberellic Acid on Pea Plant Growth

8. A graph always has axes titles. Figure 1. The Effect of Gibberellic Acid on Pea Plant Growth Time (days)

9. Figure 1. The Effect of Gibberellic Acid on Pea Plant Growth 25 20 15 10 5 1 2 3 4 5 6 Time (days after spraying ) A graph has appropriate tick marks

10. 25 20 15 10 5 1 2 3 4 5 6 Time (days after spraying ) There is a trend line for each data set. • For our purposes we will assume a linear relationship unless it is indicated otherwise.

11. 25 20 15 10 5 1 2 3 4 5 6 Time (days after spraying ) A graph should have a legend Figure 1. The Effect of Gibberellic Acid on Pea Plant Growth Gibberellic acid spray Control

12. Table Construction. • Your have control and treatment plots. • Report the mean internode length and # of leaves for all of the pea plants in the control pot. • Report the mean internode length and # of leaves for all of the peas in the treatment pot. • Report this information in the same table.

13. Table Basics • Tables always have titles. • Tables always are numbered. • Tables always have headings for columns and rows. • Tables always indicate what the units are. • Tables summarize data.

14. Table 1 Effect of Gibberellic Acid on Internode Length and Number of Leaves of Pea Plants Tables always have titles!

15. Table 1 Effect of Gibberellic Acid on Internode Length and Number of Leaves of Pea Plants Tables always are numbered.

16. Table 1 Effect of Gibberellic Acid on Internode Length and Number of Leaves of Pea Plants Tables always have headings for columns and rows. Gibberllic Acid Treatment Observation Control Mean Internode Length (cm) Mean Number of Leaves per Plant

17. Table 1 Effect of Gibberellic Acid on Internode Length and Number of Leaves of Pea Plants Gibberllic Acid Treatment Observation Control #### #### Mean Internode Length (cm)† #### #### Mean Number of Leaves per Plant † 2nd internode from apex

18. Other Data • Report your qualitative data using sentences.

19. Finishing Thoughts • Tables and Figures used in reports summarize data. • Never report the same data in both a Figure and a Table. • Always encapsulate the relevant points of a Figure or Table using data points (the numbers) in one or more well constructed sentences in the text. • Tables and Figures appear in the text of the report as soon after they are referred to as possible, not in a separate section at the end of the paper.

20. Data presentation is really black and white!