Airline industry representatives have recently argued that flying is safer than driving citing two separate studies First U S statistics show that each year there are approximately 40 000 deaths in automobile accidents versus only approximately 200 in fli

The purpose of the airline industry’s argument, elucidated in the passage above, is to convince the reader that flying is safer than driving. The industry representatives cite two pieces of evidence to support their conclusion—first, that fewer people die per year in flight; second, that airline pilots get into fewer driving accidents. To show that these arguments are reasonable, several questions need to be answered. The first question has to do with the proportion of deaths represented by the figures of annual deaths; the second has to do with the degree to which being a safe driver translates into being a safe pilot.

Suppose the CEO of a car company tried to convince shareholders that the company was succeeding in a marketing campaign to sell a certain kind of car by saying that over 10,000 cars had sold since the campaign began. The obvious question on the shareholders’ minds should be the fraction of the total number of cars sold that this figure represents. If 10,000 cars represents less than 1% of the entire market on cars for this period, presumably they would not be very pleased with the campaign. Similarly, knowing that only 200 people, versus 40,000 people, died in flight versus on the road is not informative until we know the proportion of the total number of fliers and drivers that these numbers represent. If far fewer people fly than drive, 200 could represent a large fraction of all fliers. And if the proportion of flight-deaths is higher than the proportion of car-deaths, then regardless of the total number, it would be fair to say that flying is not safer than driving. The question that needs to be answered, in other words, is how many people fly and drive each year. This would then allow us to calculate the portion of the total that these figures represent.

Turning to the second piece of evidence used to support the argument that flying is safer than driving, we learn that airline pilots are safer-than average drivers, having four times fewer accidents than the norm. In order for this fact to be convincing, several questions would need to be answered. First of all, we would need to know whether being a safe driver translates into being a safe pilot. But more than this, we would need to know what being a safe pilot means. Keep in mind that we are solely evaluating the argument that flying is safe relative to driving. So knowing that pilots are “safe fliers” is nonsensical unless we can evaluate that claim in the context of driving. Therefore, a question that needs to be answered to make this argument valid is what having a “safe pilot” means for airline passengers. An example of an answer to this question that would make the argument more valid would be that for any given hour of flight, pilots are vastly less likely to crash than for a given hour of driving. This is quite clearly a long distance away from the statement as initially phrased—evidence that the argument as-is is in need of serious revision.

Finally, we see in this passage the beginnings of a coherent argument, but more information is needed in order to fully evaluate the strength of the claims. Namely, we would need to know what fractions 200 and 40,000 represent of the entire population of fliers and drivers, respectively, and also what implications being a safe driver has for being a safe airline pilot.