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Another Cleveland Joke
Robert W. Floyd
Copyright 1983
Don't blame the typist who entered the incorrect value of the Sprenger home into
the computer. Typists always make mistakes; a well-designed information
processing system takes that into account, and detects or allows for the mistakes.
Don't blame the computer, either. It was just following orders, and, unlike
Adolph Eichmann, it had no choice in the matter. I can imagine it muttering to
itself ``This don't seem right somehow. I wish I had some way to ask somebody
about it.'' A good computer programmer always designs his programs to adequately
treat incorrect as well as correct data. Among the options common sense would
suggest to a programmer of a property tax base evaluation:
(1) Each type of property has a certain plausible maximum and minimum value.
The maximum plausible value for a house might be 120% of the previous year's
highest assessed value.
(2) Such maxima and minima might be set by neighborhoods; a single-family house
in a slum is unlikely to be worth more than $100,000, while many a house in
Shaker Heights might top $1,000,000.
(3) If the previous year's evaluation of the same property is available on a
computer file, plausible maxima and minima might be 20% above and below the
old valuation.
(4) Depending on the degree of implausibility, the computer might request
confirmation of the input by the typist:
``Valuation increased by 35% in one year. Is this confirmed?
Type Y or N.''
It might demand credentials:
``New house evaluated at $2,800,000. Evaluations over
$1,000,000 must be confirmed by county assessor or deputy.
Please enter password of confirming officer, or the word
POSTPONE.''
It might simply refuse to accept certain data.
``Valuation of single family home over $10,000,000 does not compute.
Don't mess with me or I'll raise your electric bill.''
In addition to the willingness of Cleveland's program to accept bad data, it
apparently had a second failing; the left hand did not know what the right one was
doing. The Sprenger assessment was corrected for the purposes of calculating the
Sprenger's tax bill, but not for the purpose of calculating the city's tax base.
Part of the discipline of data base management (the handling of large files of
repeatedly used data) is to avoid using multiple copies of what should be the
same data in different places; such multiple copies can lead to internal
inconsistency in the data base.
The use of a numerical code to indicate the type of building is an open
invitation to the kind of error that occured. Why not use ``R,'' rather
than 5100, to mean residence?
If you ever go to work as a programmer for Cuyahoga County, please tell them
what I said. And try to arrange to be paid by a handwritten paycheck.
(On the other hand, there's always that chance that a bi-weekly paycheck printed
by the computer might be for $510,000,750).