Re: New member checking in


Bruce Smith
 

Ted,

How did you document and analyze your "experience"? The problem with what you say is that it is subject to bias (and is demonstrably false when real data, for specific car types, is used). Memory is unfortunately a terrible instrument to use when facts are needed. 

First, as we have said ad infinitum, you need to specify car type. Coal hoppers? Sure, mostly adjoining roads. Gondolas? The regional road hypothesis holds up pretty well. Boxcars? No, your hypothesis is false. 

So let's talk about boxcar. When looking at each region, did you discount the frequency when you were looking at home road cars on the home road? If you simply look at all the railroads in the middle Atlantic region, there are more PRR cars than expected by the national pool numbers. But that's because the PRR makes up much of the route miles of the middle Atlantic region and you are counting cars on home rails, which is NOT part of this analysis. But, what about PRR cars on the B&O? What's the rate there?

The bottom line is that several extensive analyses, across much of the country, show that non-home road boxcars appear, over time, and many trains, in approximately their proportion of the national fleet. Yes, there are lots of exceptions, for example trains specifically designed to interchange with another road will be biased to that road (but other trains will have proportionally fewer of the same road), and branches with focused traffic, especially when those cars are in pools will be biased to the pool members, but for a general pool of cars, the best data to date says that the national poll percentage will produce the best results. There are and should be more PRR boxcars than SP boxcars on the Northern Pacific. 

Regards,
Bruce Smith
Auburn, Al


From: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io> on behalf of Ted Larson via groups.io <mhrreast@...>
Sent: Saturday, June 25, 2022 8:29 AM
To: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io>
Subject: [EXT] Re: [RealSTMFC] New member checking in
 
CAUTION: Email Originated Outside of Auburn.
In my experience/observation 
There is a geographic bias to freight car distribution   
Out east more out east cars
Out west more out west cars 
Vs a uniform distribution if the national fleet.  
ie many more PRR cars out east vs out west. 



--
Ted Larson
Trainweb.org/MHRR   ---   GN in 1965   ---   NASG.org 

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