Kennett takes low road with .02 limit
This article addresses an important social issue in terms of risk. The graph is clear and well labelled but it must be recognised that the vertical axis increases in a multiplicative sense. It gives the risk of an accident for drivers as a multiple of the risk if they have no alcohol in their blood. Hence at .16 a driver is 30 times more likely to have an accident than a driver with no alcohol, while at.08 a driver's risk increases by 5 times.
This is a good article to use when "interpreting graphs" is a topic of study. Younger students can be asked to interpret the meaning of the graph and older students who have been introduced to probability can be asked to write out conditional probability statements for the increased risk. For example, Pr(accident|.08 reading) = 5xPr(accident|no alcohol)
This is also a good article to use in a social science or health class when issues associated with alcohol consumption in society are addressed. Students may have an opinion on what the limit should be but this should be informed by the information on the graph.
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