How to automatically fit variogram in gstat
Hi, One option is to use the automap package, this provides the function autofitVariogram and autoKrige. Automap is available on CRAN. An alternative is to use the fit.variogram function from gstat (which automap also does). An additional comment, 8 stations is not a lot to base variogram models on. Think carefully how you want to solve this problem. Maybe you can make some kind of aggregated sample variogram that incorporates not only the data from one day, but of one month. In this way you can increase the amount of data you use to create the variogram. But still, just 8 stations looks to be quite a challenge. good luck! Paul
ZK wrote:
Dear all, I have daily pollutant measurements (CO, NO2, PM2.5 and Ozone) at 8 monitors from 2005 to 2008. My purpose is to estimate daily exposures for studying subjects using Kriging for three years. A common procedure is to plot experimental variogram and then to choose a theoretical model (e.g., exponential model or Gaussian model) with some adjustment on parameters. However, this manual way is not appropriate for my application. I am wondering how I can fit variogram in gstat automatically. I appreciate your response and best regards, Kai
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