arXiv subjects

William M Briggs

Publications and source records attributed to William M Briggs.

3 recordsLinked to original sources

arXiv2019

Fixes to the Ryden & McNeil Ammonia Flux Model

We propose two simple fixes to the Ryden and McNeil ammonia flux model. These are necessary to prevent estimates from becoming unphysical, which very often happens and which has not yet been noted in the literature. The first fix is to constrain the limits of certain of the model's parameters; without this limit, estimates from the model are seen to produce absurd values. The second is to estimate a point at which additional contributions of atmospheric ammonia are not part of a planned expert but are the result of natural background levels. These two fixes produce results that are everywhere physical. Some experiment types, such as surface broadcast, are not well cast in the Ryden and McNeil scheme, and lead to over-estimates of atmospheric ammonia.

physics.ao-ph↗

arXiv2007

Changes in number and intensity of world-wide tropical cyclones

Bayesian statistical models were developed for the number of tropical cyclones and the rate at which these cyclones became hurricanes in the North Atlantic, North and South Indian, and East and West Pacific Oceans. We find that there is small probability that the number of cyclones has increased in the past thirty years. The rate at which these storms become hurricanes appears to be constant. The rate at which hurricanes evolve into category 4 and higher major storms does appear to have increased. We also investigate storm intensity by measuring the distribution of individual storm lifetime in days, storm track length, and Emanuel's power dissiptation index. We find little evidence that, overall, the mean of the distribution of individual storm intensity is changing through time, but the variability of the distribution has increased. The cold tongue index and the North Atlantic oscillation index were found to be strongly associated with storm quality in the Western, and to a smaller extent, the Eastern Pacific oceans. The North Atlantic oscillation index was strongly associated with the increase in the rate of strong storms evolving.

physics.ao-ph↗

arXiv2006

Broccoli Reduces The Risk of Splenetic Fever! The use of induction and falsifiability in statistics and model selection

The title, a headline, and a typical one, from a newspaper's "Health & Wellness" section, usually written by a reporter who has just read a medical journal, can only be the result of an inductive argument, which is an argument from known contingent premisses to the unknown. What are the premisses and what is unknown for this headline and what does it mean to statistics? The importance--and rationality--of inductive arguments and their relation to the frequently invoked, but widely and poorly misunderstood, notion of `falsifiability' are explained in the context of statistical model selection. No probability model can be falsified, and no hope for model buidling should be sought in that concept.

math.GM↗