I base my rating on how well the book accomplished its purpose, not return on investment. As stated in the title, it was written to enable technical and statistical analysis in geographic questions. Even after 45 years of being in print, every chapter is still relevant to "modern" or "digital" GIS analysts and/or operational research analysts trying to answer "where?". Having owned it for five years, I still keep this by my desk and use it in technical GIS projects. I feel it treats geographic analysis in equal or better clarity, detail and depth than those published by ESRI Press.