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Evaluation of the williams-type model for barley yields in north dakota and minnesota
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Copyright Year | 1981 |
| Description | The Williams-type yield model is based on multiple regression analysis of historial time series data at CRD level pooled to regional level (groups of similar CRDs). Basic variables considered in the analysis include USDA yield, monthly mean temperature, monthly precipitation, soil texture and topographic information, and variables derived from these. Technologic trend is represented by piecewise linear and/or quadratic functions of year. Indicators of yield reliability obtained from a ten-year bootstrap test (1970-1979) demonstrate that biases are small and performance based on root mean square appears to be acceptable for the intended AgRISTARS large area applications. The model is objective, adequate, timely, simple, and not costly. It consideres scientific knowledge on a broad scale but not in detail, and does not provide a good current measure of modeled yield reliability. |
| File Size | 8972044 |
| Page Count | 51 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19830006298 |
| Archival Resource Key | ark:/13960/t9r25rz3s |
| Language | English |
| Publisher Date | 1981-12-01 |
| Access Restriction | Open |
| Subject Keyword | Earth Resources And Remote Sensing Root-mean-square Errors Barley Atmospheric Temperature Earth Resources Program Agristars Project North Dakota Crop Inventories Yield Mathematical Models Minnesota Regression Analysis Precipitation Meteorology Ntrs Nasa Technical Reports ServerĀ (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |