Demo of Statistical Analysis presentation for the Developing an On-farm Experiment’ Webinar

Demo of Statistical Analysis presented during the SSARE 'Developing an On-farm Experiment’ Webinar

1. Why farmer-led research is so important “Farmer-driven innovations …improve profitability, stewardship and quality of life” ( https://www.sare.org ) Sustainable agriculture depends on site-specific farming ( https://southern.sare.org/about/?highlight=site-specific )

2. Is small-plot research representative of commercial farms? “Edge effects” in small-plot research

3. Baseball and The Scientific Method

4. The World Series of Baseball and the Scientific Method n Observation n Idea (=Hypothesis) n Test n Conclusion

5. Baseball and the importance of replication

6. Why randomize?

7. Why randomize? 1 1 1 2 2 2 3 3 3

8. Why randomize? 3 1 2 3 1 2 3 2 1

9. Testing hypotheses

10. Analysis of data

11. EXPERIMENTAL DESIGN

12. Orange treatment, rep 1 Gray treatment, rep 1 Gray treatment, rep 2 Orange treatment, rep 2 Orange treatment, rep 3 Orange treatment, rep 4 Gray treatment, rep 3 Gray treatment, rep 4 SAMPLING

13. Orange treatment, rep 1 Gray treatment, rep 1 Gray treatment, rep 2 Orange treatment, rep 2 Orange treatment, rep 3 Orange treatment, rep 4 Gray treatment, rep 3 Gray treatment, rep 4 SAMPLING (cont’d) 78 59 89 01 36 55 71 05

14. Orange treatment, rep 1 Gray treatment, rep 1 Gray treatment, rep 2 Orange treatment, rep 2 Orange treatment, rep 3 Orange treatment, rep 4 Gray treatment, rep 3 Gray treatment, rep 4 SAMPLING (cont’d) 78 59 89 01 36 55 71 05

15. Orange treatment, rep 1 Gray treatment, rep 1 Gray treatment, rep 2 Orange treatment, rep 2 Orange treatment, rep 3 Orange treatment, rep 4 Gray treatment, rep 3 Gray treatment, rep 4 SAMPLING (cont’d) 78 59 89 01 36 55 71 05

16. ORANGE TREATMENT GRAY TREATMENT

17. Treatment Average Standard deviation Do these averages differ? Orange 46.5 35.4 P-value = 0.83 Gray 52.0 34.8 --- Mock Yields from Orange vs. Gray Mock-Experiment https://www.calculatorsoup.com/calculators/statistics/descriptivestatistics.php AND https://www.medcalc.org/calc/comparison_of_means.php

18. Exercise in hypothesis testing Work in small groups to come up with at least one hypothesis (=idea) for your farm

19. What testable ideas did you come up with?

20. How to test your hypothesis? How to implement your treatments? This is the only time experimental treatments are treated differently from the controls

21. A control treatment is usually either a common practice, or no practice

22. Controls Turf trials: experimentals are applied in 2 gallons water per 1000 ft2 What are appropriate controls in our turf trials? Untreated Treated

23. Selected Experimental Designs and Statistical Calculators

24. Observational study: Valuable but not experimental