I agree with Malcolm. The very notion that box cars were distributed on all railroads across the country in proportion to ownership is patently absurd on its face. As has been noted before, and mentioned here in some respects, there were just too many variables and oddities and contingencies, etc. for such a hypotheses to work in reality. All one has to do is look at some photos of rail yards and freight trains from a good sample of the US and one would instantly recognize the randomness, and sometimes predictable, patterns of box car distribution across the country. The reason people get so excited about seeing a BAR red white and blue box car in Dallas, Texas is because it is a rarity, just as a WP car in Boston would be a wonder to behold. The Granger railroads kept a high percentage of their fleets on their home irons, and especially the CB&Q. I lived in Lubbock, Texas for four years while in school many years ago, when the single sheathed box cars were predominant on the Q and about all you would see on the High Plains of the Panhandle at that time were these great SS box cars. Out here in the PNW during the BN days one could see long freight trains with almost nothing but BN cars, along with some still un re-painted NP and GN cars, with a smattering of other roads, even some strays form the SouthEast at times.
Proportional distribution across all railroads on some mathematical formula and theory is just an exercise in lahlah land. Fun, interesting, and helpful in a tiny degree as previously noted, but not applicable or transferable to model railroad situations (aside from the virtual railroads, where anything is possible).
To: STMFC@...: mlaughlinnyc@...: Mon, 18 Aug 2008 16:06:46 +0000Subject: [STMFC] Re: freight car distribution - rejecting the equal distribution hypothesis.
It has been stated that the burden of proof is on me that box cars were not distributed on all railroads in proportion to ownership. The burden of proof notion is not applicable here because it is not possible to "prove" either side of the argument, which could be done only if car accounting records from the period were available. Absent any method of proof, we have to fall back on logic based on known practices and traffic flows at the time.Here are some variables that work against proportional distribution across all railroads.- Car service rules. While we know that car service rules were not always observed, we also know that many railroads did observe them most of the time. This greatly reduces the likelihood of an FEC car in Oregon or a WP car in Maine.- Length of haul. I believe that the average length of haul of a carload was in the area of 300 to 500 miles. This was for all car types and probably unknowable by specific type. Given our known bias, of undeterminable magnitude, toward loading in home road cars, the probability of seeing any mark on any railroad is biased downward by its distance from the owner.- Seasonal tides – the grain harvest for example. Nationwide there was a fixed fleet of cars usable for grain loading. The big Midwest harvest began in Oklahoma and nearby areas and over the course of a few months moved north to the Dakotas. The car fleet moved north also, quite inconsistent with the proportional distribution hypothesis. The AAR issued movement orders to get cars from the east to grain loading areas was another source of bias.- Surpluses and shortages. They varied widely by season, region and type of load. The largest 40 ft. narrow door box car shortage crises were in the best grain crop years. When the shortage was over, many cars went home to rest for a few months. A peak grain harvest in a time of business recession would really skew the distribution.- Suitability for loading. Some cars were more suited for paper loading, others for grain, BCK cars for flour, etc. Locations of large users of newsprint strongly biased the destination areas of cars with marks of the paper loading railroads. Railroads serving lumber producers a much higher proportion of cars dimensionally suitable for lumber. The multitude of such situations caused many pockets of ownership concentration.- Cars out of service. On the NYC we had thousands of XM box cars out of service awaiting rebuilding or rarely used because of obsolescence. The proportion of such cars varied widely among railroads. As a result the listings in the ORER was only approximately representative of the cars actually hauling freight.I could probably think of other factors given some time, but I think this is enough to say that the equal distribution hypothesis requires a huge leap of faith. Remember that it is a theory developed in a quest to answer a question that may not be answerable and uses data that is only indirectly related to the end result and purportedly validated by a very small sample. When statistical results vary widely from what our knowledge of the real world leads us to expect, we should first question the validity of the statistical method.BTW, that storage to shortage phenomenon is a reason that average loads per car per year gives us no useful information about turnaround time of cars actually in use. And it didn't mean that long tracks of stored cars. That surplus was distributed a day or two at a time over thousands of yards and stations - cars awaiting distribution for a day or two more than they would have in a time of shortage.