Book Image

QGIS Blueprints

By : Ben Mearns
Book Image

QGIS Blueprints

By: Ben Mearns

Overview of this book

Table of Contents (14 chapters)
QGIS Blueprints
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Chapter 6. Estimating Unknown Values

In this chapter, we will use interpolation methods to estimate the unknown values at one location based on the known values at other locations.

Interpolation is a technique to estimate unknown values entirely on their geographic relationship with known location values. As space can be measured with infinite precision, data measurement is always limited by the data collector's finite resources. Interpolation and other more sophisticated spatial estimation techniques are useful to estimate the values at the locations that have not been measured. In this chapter, you will learn how to interpolate the values in weather station data, which will be scored and used in a model of vulnerability to a particular agricultural condition: mildew. We've made the weather data a subset to provide a month in the year during which vulnerability is usually historically high. An end user could use this application to do a ground truthing of the model, which is, matching high...