In this memo West Egg’s mayor reasons that West Egg’s residents are now strongly
committed to recycling, and projects that the city’s landfill will not be filled to capacity until
considerably later than anticipated two years ago. To support this projection the mayor cites (1)
a twofold increase in aluminum and paper recycling by West Egg residents over the last two
years, (2) an impending twofold increase in charges for trash pickup, and (3) a recent survey in
which 90% of respondents indicated that they intend to do more recycling in the future. For
several reasons, I am not convinced that the mayor’s projection is accurate.
To begin with, in all likelihood aluminum and paper account for only some of the materials
West Egg’s residents can recycle. Perhaps recycling of other recyclable materials--such as
plastic and glass--has declined to the point that the total amount of recycled materials has also
declined. If so, then the mayor could hardly justify the claim that West Egg’s residents are
becoming more committed to recycling.
Another problem with the argument is that an increase in the amount of recycled materials
does not necessarily indicate a decrease in the total amount of trash deposited in the city’s
landfill. Admittedly, if West Egg residents previously disposed of certain recyclable materials
that they now recycle instead, then this shift from disposal to recycling would serve to reduce
the amount of trash going to the landfill. However, the mayor provides no evidence of such a
shift.
Moreover, the argument overlooks the strong possibility that the recycling habits of West
Egg residents are not the only factor affecting how quickly the landfill will reach capacity. Other
such factors might indude population and demographic shifts, the habits of people from
outside West Egg whose trash also feeds the landfill, and the availability of altemative disposal
methods such as burning. Thus regardless of the recycling efforts of West Egg residents the
landfill might nevertheless reach full capacity by the date originally forecast.
Yet another problem with the argument involves the mayor’s implicit claim that increased
charges for trash pickup will serve to slow the rate at which the landffil is reaching capacity.
This claim relies on the unlikely assumption that West Egg residents have the option of
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recycling--or disposing in some other way--much of what they would otherwise send to the
landfill. However, it is likely these residents have no practical choice but to send some refuse
to the landfill. The greater the amount, the less likely higher trash charges would have any
effect on how quickly the landffil reaches capacity.Finally, the mayor provides no evidence that the survey’s respondents are representative of
the overall group of people whose trash goes to the city’s landfill. Lacking such evidence, it is
entirely possible that people inclined to recycle were more willing to respond to the survey than
other people were. In short, without better evidence that the survey is statistically reliable the
mayor cannot rely on it to draw any firm conclusions about the overall recycling commitment of
West Egg residents--let alone about how quickly the landfill will reach capacity.
In sum, the mayor’s projection is simply not credible, at least based on the memo. Rather
than relying solely on questionable recycling statistics, the mayor should provide direct
evidence that the amount of trash going to the landfill is declining and that this trend will not
reverse itself anytime soon. To better assess the accuracy of the mayor’s projection it would be
useful to know who besides West Egg residents contributes trash to the land fLU, and whether
the amount of trash those people contribute is declining or is likely to decline in the near future.
Argument 11
The following appeared in a memo from a vice president of Alta Manufacturing.
"During the past year, Alta Manufacturing had thirty percent more on-the-job accidents than
nearby Panoply Industries, where the work shifts are one hour shorter than ours. Experts
believe that a significant contributing factor in many on-the-job accidents is fatigue and sleep
deprivation among workers. Therefore, to reduce the number of on-the-job accidents at Alta
and thereby increase productivity, we should shorten each of our three work shifts by one hour
so that our employees will get adequate amounts of sleep."
This editorial recommends that Alta Manufacturing reduce its work shifts by one hour each in
order to reduce its on-the-job accident rate and thereby increase Alta’s productivity. To support
this recommendation the author points out that last year the number of accidents at Alta was
30% greater than at Panoply Industries, where work shifts were one hour shorter. The author
also cites certain experts who believe that many on-the-job accidents are caused by fatigue
and sleep deprivation. I find this the argument unconvincing for several reasons.
First and foremost, the author provides absolutely no evidence that overall worker
productivity is attributable in part to the number of on-the-job accidents. Although common
sense informs me that such a relationship exists, the author must provide some evidence of
this cause-and-effect relationship before I can accept the author’s final conclusion that the
proposed course of action would in fact increase Alta’s productivity.Secondly, the author assumes that some accidents at Alta are caused by fatigue or sleep
deprivation. However, the author overlooks other possible causes, such as inadequate
equipment maintenance or worker training, or the inherent hazards of Alta’s manufacturing
processes. By the same token, Panoply’s comparatively low accident rate might be attributable
not to the length of its work shifts but rather to other factors, such as superior equipment
maintenance or worker training. In other words, without ruling out alternative causes of
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on-the-job accidents at both companies, the author cannot justifmbly conclude that merely by
emulating Panoply’s work-shift policy Alta would reduce the number of such accidents.
Thirdly, even assuming that Alta’s workers are fatigued or sleep-deprived, and that this is the
cause of some of Alta’s on-the-job accidents, in order to accept the author’s solution to this
problem we must assume that Alta’s workers would use the additional hour of free time to
sleep or rest. However, the author provides no evidence that they would use the time in this
manner. It is entirely possible that Alta’s workers would use that extra hour to engage in some
other fatiguing activity. Without ruling out this possibility the author cannot convincingly
conclude that reducing Alta’s work shifts by one hour would reduce Alta’s accident rate.
Finally, a series of problems with the argument arise from the scant statistical information on
which it relies. In comparing the number of accidents at Alta and Panoply, the author fails to
consider that the per-worker accident rate might reveal that Alta is actually safer than Panoply,
depending on the total number of workers at each company. Second, perhaps accident rates
at the two companies last year were aberrations, and during other years Alta’s accident rate
was no greater, or even lower, than Panoply’s rate. Or perhaps Panoply is not representative
of industrial companies generally, and that other companies with shorter work shifts have even
higher accident rates. In short, since the argument relies on very limited statistical information I
cannot take the author’s recommendation seriously.