Identifying Factors for Corn Yield Prediction Models and Evaluating Model Selection Methods

  • Chang Jiyul (Center for Biocomplexity Studies, South Dakota State University) ;
  • Clay David E. (Plant Science Department, South Dakota State University)
  • Published : 2005.09.01

Abstract

Early predictions of crop yields call provide information to producers to take advantages of opportunities into market places, to assess national food security, and to provide early food shortage warning. The objectives of this study were to identify the most useful parameters for estimating yields and to compare two model selection methods for finding the 'best' model developed by multiple linear regression. This research was conducted in two 65ha corn/soybean rotation fields located in east central South Dakota. Data used to develop models were small temporal variability information (STVI: elevation, apparent electrical conductivity $(EC_a)$, slope), large temporal variability information (LTVI : inorganic N, Olsen P, soil moisture), and remote sensing information (green, red, and NIR bands and normalized difference vegetation index (NDVI), green normalized difference vegetation index (GDVI)). Second order Akaike's Information Criterion (AICc) and Stepwise multiple regression were used to develop the best-fitting equations in each system (information groups). The models with $\Delta_i\leq2$ were selected and 22 and 37 models were selected at Moody and Brookings, respectively. Based on the results, the most useful variables to estimate corn yield were different in each field. Elevation and $EC_a$ were consistently the most useful variables in both fields and most of the systems. Model selection was different in each field. Different number of variables were selected in different fields. These results might be contributed to different landscapes and management histories of the study fields. The most common variables selected by AICc and Stepwise were different. In validation, Stepwise was slightly better than AICc at Moody and at Brookings AICc was slightly better than Stepwise. Results suggest that the Alec approach can be used to identify the most useful information and select the 'best' yield models for production fields.

Keywords

References

  1. Burnham, K. P. and D. R Anderson. 2001. Kullback-Leibler information as a basis for strong inference in ecological studies. Wildlife Research. 28 . 111-119 https://doi.org/10.1071/WR99107
  2. Bumham, K. P. and D. R. Anderson. 2002. Model selection and multimodel inference: A practical pnformation-theoretic approach. Springer-Verlag, New York, New York, USA, 488p
  3. Chang, J., D. E Clay, K. Dalsted, S A. Clay, and M. O'Neill, 2003. Com (Zea mays L.) Yield prediction using multispectral and multidate reflectance. Agron. J. 95 : 1447-1453 https://doi.org/10.2134/agronj2003.1447
  4. Chatterjee, S, A. S Hadi, and B. Price, 2000 Regression analysis by example. (3rd ed ). John Wiley & Sons, Inc. New York, New York, USA, 359p
  5. Clay, D. E , J. Chang, D. D. Malo, C. G. Carlson, C. L. Reese, S. A Clay, M Ellsbury, and B. Berg 2001. Factors influencing spatial variability of soil apparent electrical conductivity. Commun. Soil Sci. Plant Anal 32: 2993-3008 https://doi.org/10.1081/CSS-120001102
  6. Johnson, D 1998. Applied multivariate methods for data analysts. Duxbury Press
  7. International Thomson Publishing Inc. Pacific Grove, CA, USA, 567p
  8. Lems, J., D. E. Clay, D Humburg, T. A. Doerge, S. Christopherson, and C. L. Reese. 1999 Yield monitors-Basic steps to ensure system accuracy and performance. SSMG-31. In D.E. Clay et at. (ed.) Site specific management guidelines Potash and Phosphate Institute, Norcross, GA
  9. Olsen, S. Rand L. E. Sommers. 1982. Phosphorus. p 403-430. In A. Klute (ed.) Methods of soil analysis. Part 2, 2nd ed. ASA. Madison, WI
  10. SAS Institute. 1995. SAS/INSIGHT User's Guide (Version 6, 3rd ed.) SAS Inst., Cary, NC
  11. Staggenborg, S. A. and R. K. Taylor. 2000. Predicting gram yield variability With infrared Images. [CD-ROM computer file] In P.C. Robert et at (ed.). Proceedings of the 5th International Conference on Precision Agriculture. July 16-19, 2000. Bloomington, MN. ASA-CSAA-SSSA, Madison WI
  12. Weigand, C. L., C. Yang, and J. M. Bradford. 1999. Mapping soil and yield variations using aerial videography, GIS, ground observations, Image analysis, and yield monitors p 151-162 In Proc, 17th Biannual Workshop on Color Photography and Videography in Resource Assessment. May 5-7, 1999
  13. Westphal, M. I., S. A. Field, A. J. Tyre, D Paton, and H. P. Possingham. 2003. Effects of landscape pattern on bird species distribution in the Mt. Lofty Ranges, South Australia. Landscape Ecology. 18.413-426 https://doi.org/10.1023/A:1026115807529