# Tobler's first law of geography

The first law of geography according to Waldo Tobler is "Everything is related to everything else, but near things are more related than distant things."[1]

This observation is embedded in the gravity model of trip distribution. It is also related to the law of demand, in that interactions between places are inversely proportional to the cost of travel, which is much like the probability of purchasing a good is inversely proportional to the cost.

It is also related to the ideas of Isaac Newton's Law of universal gravitation and is essentially synonymous with the concept of spatial dependence that forms the foundation of spatial analysis. Furthermore, it is the founding principle upon which the understanding and corrective measures for spatial autocorrelation have been based upon.[2]

The link structure of Wikipedia's collection of geolocated articles has been demonstrated to be consistent with Tobler's first law of geography.[3] Recent research has shown that, according to semantic analysis on geo-referenced Wikipedia articles, while as TFL suggests, near things are on average more related than distant things, this is only consistently true within a specific distance range. Beyond that distance, TFL no longer holds.[4]

## References

1. ^ Tobler W., (1970) "A computer movie simulating urban growth in the Detroit region". Economic Geography, 46(2): 234-240.
2. ^ Luc Anselin, Spatial Econometrics, 1999 <https://csiss.ncgia.ucsb.edu/aboutus/presentations/files/baltchap.pdf>
3. ^ Hecht, B., Moxley, E.: . In Hornsby, K.S., Claramunt, C., Denis, M., Ligozat, G., eds.: Spatial Information Theory, 9th International Conference, COSIT 2009, Aber Wrac'h, France, September 21-25, 2009, Proceedings. Volume 5756 of Lecture Notes in Computer Science., Springer (2009) 88-105
4. ^ Li, T. J-J., Sen, S., Hecht, B.: . In Proceedings of the 22nd ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems. New York: ACM Press.