Comments, with reply, on "On the hazard rate of the lognormal distribution" by A.L. Sweet

In the above-named work (see ibid., vol.39, p.325-8, Aug 1990), A.L. Sweet calls attention to some incomplete or inaccurate representation of the hazard rate of lognormal distributions. His principal concern apparently is that these representations may lead modelers to overlook an important property of the lognormal distribution: its hazard rate increases and then decreases as a function of elapsed time. He also provides approximations for the location and value of the hazard rate maximum. The commenter observes that, as theoreticians are likely to have ready access to expanded tables of the normal distribution and unlikely to have need for the approximations, the Sweet paper was aimed at practitioners dealing with actual data. The commenter cautions such practitioners that some serious problems, unrelated to table availability or approximation accuracy, arise if sigma /sub 1n(T)/ is high or low. In his reply, Sweet remarks that the commenter is correct in assuming that Sweet's work was aimed at practitioners-specifically, at those being introduced to the lognormal distribution for the first time by reading about it in the books referenced in Sweet's article.<
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