Re: Interpreting Copeland interchange data

jaley <jaley@...>

On Feb 28, 6:19pm, Tony Thompson wrote:
Subject: Re: [STMFC] Interpreting Copeland interchange data
Jeff Aley wrote:
      If I take the 1951 RI data + the 1947 UP data, I get 949 cars
week.  Of course, that's ALL loaded cars, not just reefers.  Perhaps
should only count the difference between the "TO" and "FROM"
loads as the reefers?
I'm sure RI also handled westward empty reefers on the Golden State
route, destined to southern California via Tucson.


I am also sure that RI handled westward empties. But the
interchange reports are for loaded cars only.

So, taking the 1952 Kansas City RI <--> WAB example, we have:

My hypothesis is that 1,536 of the cars interchanged (both TO and
FROM) are "normal" or "generic" traffic, whereas the (13,071 - 1,536 = )
11,535 excess cars sent TO the Wabash were probably reefers, which came
back empty and are therefore not represented in the "FROM" data.

I would further hypothesize that an analagous situation would
apply if one were to analyze the traffic of a coal-hauling road. I.e.
since coal hoppers tend to return empty, one would see a large bias for
the loaded traffic in a particular direction.



Jeff Aley jaley@...
DPG Chipsets Product Engineering
Intel Corporation, Folsom, CA
(916) 356-3533

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