Greetings contributors...this is an amazingly informative thread. I am working on an independent study for M.S., the topic is "Land Use Influence on Water Degradation".
My dependent variable is the length (in meters) of impaired rivers/streams expressed as a percentage of the length of all rivers and streams in the sub-watersheds of a larger watershed.
Explanatory variables are both percentages and Percentage(log) of agriculture, grass/grain/pasture, development, and Forest (to explore a negative relationship), expressed as percentages per subwatershed.
I have run numerous OLS processes, and none of the models gets past .9, dismally low considering I would like to see 75. Even when i isolate the watersheds with impaired water I still only get up to 35 (a drastic increase, but still low). Moran's-I is good though, no spacial auto-correllation in any of my models.
Would GWR be better for this kind of analysis? What else should I try?
Also...if I take the (log) of an explanatory variable, should I also take the log of the dependent variable, or would that simply nullify the transformation?
thanks!
Chris