What books, journals, and/or electronic resources have you found most valuable for expanding your knowledge in the GIS field, and why?
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Not entirely a GIS Book but very helpful in many map design problems is Tufte's The Visual Display of Quantitative Information
PostGIS In Action by Regina Obe and Leo Hsu http://www.manning.com/obe/
An excellent tutorial and resource on spatial databases in general and PostGIS in particular. The book is currently available through Manning's Early Access Program in .pdf format, the paper version will be out relatively soon.
Geospatial Analysis: A Comprehensive Guide to Principles, Techniques, and Software Tools Smith, Goodchild, Longley 2007
Entire text is online: http://www.spatialanalysisonline.com/
A solid guide to how geospatial analysis work, particularly with respect to GIS. The book emphasizes conceptual workflows, but still provides the basic math. I found the math quite helpful for creating my own code and also getting an understanding of what's happening under the hood in contemporary GIS.
The best computational geometry book. Very good at explaining (with illustrations) the various algorithms and concepts often used in GIS, such as triangulation, indexing, calculating intersection, shortest paths etc.
Map Projections: A Working Manual (PDF, 380pages) by John P. Snyder
Here's my "recent" favourites, both cartography-related:
Unfortunately, and this is kind of sad, I have to admit that I haven't read a single GIS book in years.
The basic principles and practices of GIS haven't changed more than incrementally in the last half-decade, and the cool new technologies--commercial mapping APIs, KML, REST, location-based games and services, etc--have all been advancing at a frenetic pace since 2005 (note the publication date of the two books above)
If new technology matters to you (and it should) and you think you can rely on books, you may as well give up and go home. To survive in this environment, you need to be adept with blogs and online documentation, and be willing to experiment.
Cartographic Relief Presentation by Eduard Imhof is the single best book I've read on cartography to date. Before ESRI Press republished the book in 2007 the only way to get was through inter-library loan via the University networks, and wait a number of months. It's still worth reading the original 1965 (Swiss/German) or 1982 (English) edition if you can as the reprint moves all the colour plates to the back of the book, and there is (an unavoidable) shift in colours and line detail. Cartographic Relief Presentation is more than forty years old, and still relevant. There's even an arcgis tool and photoshop method modelled after his Swiss Style Shaded Relief.
There are a hundred quotes I could pull out, but this is the one which strikes me today: "it is a mistake to believe the quality of a map depends primarily on the expenditure of money, time and labor. ...more decisive are the capability, experience, and expertise of the mapmaker. The expert always uses the simplest approach. ... He can show with a few lines what an unskilled worker would require many lines to depict. ...high density of information with poor selection is less efficient than a map with less content but good selection.
Section of school wall map of the Canton of Zurich, 1:50 000. 1934 (see exhibit)
I'm biased towards transportation, but here a few books (mostly reference type) I cannot live without:
- Field related: NCHRP Travel Demand Modeling (report 365)
- Field related: Transit Quality of Service Manual - TCRP 100 Note there is an outdated rural version of this that I DO NOT recommend
- Field related: Forecasting Demographics
Burrough and McDonnell's Principles of Geographic Information Systems is also a good one. It provides you with most of the basic and higher level GIS concepts. It is software agnostic which means you can very much apply the principles in any tool you use.
Desktop GIS: Mapping the Planet with Open Source Tools by Gary Sherman.
It's the first book I give out to folks when they're looking to learn a little about GIS and open source.
At the University of Tennessee Knoxville I took Quantitative Methods in Geography (as part of my undergraduate degree), and the text we used in the class was Elementary Statistics for Geographers 3rd Edition. I kept this book and reference to it frequently. It provides very thorough explanations of introductory statistics (descriptive and inferential statistics) with a focus on geography. The last two sections focus on spatial and temporal statistics.
I really like Mapping Hacks by Schuyler Earle, Rich Gibson, and Jo Walsh. http://www.amazon.com/Mapping-Hacks-Tools-Electronic-Cartography/dp/0596007035/
The book is divided up into 100 very creative 'hacks' that teach you about mapping, spatial data, opensource tools to work with data, and in the process inspire you to create or tackle the geospatial problems/hacks that you encounter in your work or personal life. One of my favorites is 'Will the Kids Barf'. It examines road sinuosity by comparing straight line distance with actual road distance to come up with an index to predict if the kids will get car sick.
This book It was published in 2005, so some of the references to APIs, etc. are a little dated, but the creativity, concepts, and inspiration are still very current.
I don't have room for the Klencke Atlas :( http://mapperz.blogspot.com/2010/01/klencke-atlas-big-maps-in-big-book.html
Great book with algorithms with nice, clear explanations of the maths behind them and implementations, which are very robust and (usually) as fast as they get. Very good for matrices, fitting, statistics... The 3rd edition includes a chapter on computational geometry, which is especially useful in GIS.
This book on GIS Principles, which is part of an educational series form the University of Twente GIS department, gives very good explanation on the subject. People who are new to GIS can gather good basic information from it.
They also have a very nice book on the principles of remote sensing.
The best part of it is that both the Ebooks are available free online on their website here.
I'm using the AAG's GIS&T Body of Knowledge as a guideline for my studying efforts.
It doesnt contain theory, but indicates what's the next logical step and where I should look for it. It contains extensive references and explain the core learning units of GI and GIScience.
The Coming Singularity by Ray Kurzweil, has some food for thought, although I don't agree with a lot of what he says. It won't take that much intelligence for a sentient computer network to realize the largest threat to his/her planet are the humans.
Perhaps GIS should be the fourth horseman of the apocalypse, next to Genetics, Nanotechnology and Robotics.
Update: OK, I guess I should suggest something more immediately useful:
Foundations of Multidimensional and Metric Data Structures by Hanan Samet is excellent if you want a clear explanation of algorithms.