Hostname: page-component-77c89778f8-7drxs Total loading time: 0 Render date: 2024-07-24T05:27:11.459Z Has data issue: false hasContentIssue false
  • English
  • Français

A Statistical Analysis for Area-of-Influence Experiments

Published online by Cambridge University Press:  12 June 2017

Nicholas Jordan
Nicholas Jordan*
Affiliation:
Div. Sci., Northeast Mo. State Univ., Kirksville, MO 63501
Get access Rights & Permissions [Opens in a new window]

Abstract

Area-of-influence (AOI3) experiments measure the effect of a single weed on crop growth at intervals away from the weed plant. Effects of treatment variables, e.g., weed species or control measures, on the AOI of a single weed can be estimated. AOI experiments can be analyzed by regression of crop growth on distance from the weed plant, but this analysis violates an important regression assumption: independece of observations. Statistical dependence can occur among successive observations along the row because uncontrolled sources of variation are likely to act in similar ways on adjacent individuals. Multivariate analysis of variance (MANOVA) is a statistical technique that accounts for dependencies among crop growth measurements along the row. The technique tests three hypotheses: first, that different treatments cause weed AOI to differ in spatial distribution of competitive effects; second, that different treatments cause weed AOI to differ in size; and third, that the weed has an effect, i.e., crop growth near the weed differs from growth away from weed. MANOVA can be applied to most common experimental designs, e.g., randomized blocks or split plots, and can be implemented on various mainframe and microcomputer statistical packages.

Keywords

Weed thresholdsweed competitionprofile analysis of variancemultivariate methods
Type
Research
Information
Weed Technology , Volume 3 , Issue 1 , March 1989 , pp. 114 - 121
Copyright
Copyright © 1989 by the Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

1. Aldrich, R. J. 1987. Predicting crop yield reductions from weeds. Weed Technol. 1:199–206.Google Scholar
2. Draper, N. R., and Smith, H. 1981. Applied Regression Analysis, Second Edition. John Wiley and Sons, New York, p. 23.Google Scholar
3. Gonsolus, J. L., and Coble, H. D. 1986. The area of influence approach to measuring weed interference effects on soybeans. Abstr. Weed Sci. Soc. Am. 26:10.Google Scholar
4. Harris, R. J. 1975. A Primer of Multivariate Statistics. Academic Press, Inc., New York, p. 106–108.Google Scholar
5. Harris, R. J. 1976. A Primer of Multivariate Statistics. Academic Press, Inc., New York, p. 67–75.Google Scholar
6. Harris, R. J. 1975. A Primer of Multivariate Statistics. Academic Press, Inc., New York, p. 118–125.Google Scholar
7. Harris, R. J. 1975. A Primer of Multivariate Statistics. Academic Press, Inc., New York, p. 22.Google Scholar
8. Harris, R. J. 1975. A Primer of Multivariate Statistics. Academic Press, Inc., New York, p. 231–233.Google Scholar
9. SAS Institute. 1985. SAS/STAT Guide for Personal Computers, Version 6 Edition. SAS Institute, Cary, NC, p. 186–260.Google Scholar
10. Morrison, D. F. 1976. Multivariate Statistical Methods, Second Edition. McGraw-Hill, New York, Chap. 5.Google Scholar
11. Morrison, D. F. 1976. Multivariate Statistical Methods, Second Edition. McGraw-Hill, New York, p. 205–212.Google Scholar
12. Oliver, L. R. 1987. Principles of threshold research. Abstr. Weed Sci. Soc. Am. 27:93.Google Scholar
13. Ripley, B. D. 1981. Spatial Statistics. John Wiley and Sons, New York, p. 98.CrossRefGoogle Scholar
14. Simms, E. L., and Burdick, D. S. 1988. Profile analysis of variance as a tool for analyzing correlated responses in experimental ecology. Biom. J. 30:229–242.CrossRefGoogle Scholar
15. Sokal, R. R., and Rohlf, F. J. 1981. Biometry, The Principles and Practice of Statistics in Biological Research, Second Edition. W. H. Freeman and Company, New York, p. 242–262.Google Scholar
16. Spitters, C.J.T. 1979. Competition and Its Consequences for Selection in Barley Breeding. Pudoc, Wageningen, p. 40.Google Scholar
17. Timm, N. H. 1975. Multivariate Analysis with Applications in Education and Psychology. Wadsworth Publishing Co., Belmont, CA, p. 444–452.Google Scholar
18. Timm, N. H. 1975. Multivariate Analysis with Applications in Education and Psychology. Wadsworth Publishing Co., Belmont, CA, p. 243.Google Scholar
19. Timm, N. H. 1975. Multivariate Analysis with Applications in Education and Psychology. Wadsworth Publishing Co., Belmont, CA, Chap. 5.Google Scholar