Historic US GIS transportation SHP files

Jeremy Atack writes to EH.net:



I have posted my historical GIS transportation SHP files for the Lower 48 states from this nation’s founding through (approximately) 1911 on my www site https://my.vanderbilt.edu/jeremyatack/data-downloads/.  Each transportation mode–canals, steamboat-navigated (as opposed to navigable) rivers, and railroads–has its own archive ZIP file which contains the complete series of files (projection, database and polyline files, etc.) required by ESRI’s ArcGIS and ArcGIS Pro.  These are collectively referred to as “a SHP file” though there are actually multiple files for each mode of transportation.  Once unpacked, these files for each SHP must be kept together and should only be edited using a GIS program.  If corrupted, the entire SHP file will become unusable.

The metadata file (.XML) briefly describes the contents of each SHP, the manner in which it was created, and summarizes any edits since these files were originally posted.  Issues relating to the creation of these SHP files are discussed in much greater detail in the documentation file also appearing at https://my.vanderbilt.edu/jeremyatack/data-downloads/


This looks like a fantastic resource for anyone doing historic analysis of intercity network evolution. Now if only someone would digitize and standardize historic urban transit networks with modern GTFS coding …

Our use of impact factors is backwards

Academics incorrectly use impact factor (IF) to judge the quality and impact of an article.

The only factor to judge the quality of an article is the article itself, and that is subjective.

The only way to measure its impact is its citations (in peer-reviewed journals or elsewhere, like popular media).

If an article published in a low impact factor (IF)  journal has 100 citations, and one in a high IF journal has 100 citations, the first should be more appreciated, since it does not benefit from the spillovers of the journal reputation. It is overcoming a disadvantage.

Thus a high citation article in a low IF factor journal is likely better than one in a high IF journal (if citations are an indicator of quality, and citations are increased with spillover effects — which people must believe otherwise why try to publish in high IF journals). Impact Factor should only be used to discount article citations, not as a positive metric in tenure and promotion.

I have heard all the reasons. IF is an indicator if the author publishing in the “right places”. It’s harder to get published in a high IF journal (likely true, but not as true as you think). There aren’t enough citations by the time a tenure decision has to be made, so this is a surrogate.


Read the actual papers. If you won’t read the papers (and/or don’t know enough to ascertain originality), trust their colleagues. At any rate, if it’s not in your area, why is the system structured to give you a vote on their academic merit? Judge their teaching, or their collegiality, but not their output.