No, I'm not making this up - people who prefer the (old-fashioned? classic?) non-Bayesian kind of probability analysis really do call themselves 'frequentists'.
Both kinds of analysis deal with the general problem that we can't absolutely know the truth, but must use samples and/or tests to approximate it. Here's what I think the differences are:
The classic approach thinks in terms of samples of the real world, and calculates how closely the samples are likely to reflect reality. If one sample from a bacterial culture, plated on novobiocin agar, gives 28 (NovR) colonies, and a parallel sample (same volume) on plain agar gives 386 colonies, we can calculate the probability that the whole culture has 28/386 NovR cells. We can use replicate samples to estimate the error in, for example, measuring the volumes of culture we used.
The Bayesian approach thinks in terms of the reliability of our information and tests, and calculates how the result of a test changes our previous estimate about reality. For example, based on previous similar experiments we might have estimated the NovR frequency at 15%. But we also know that the plating test isn't perfect, and we can estimate how likely it is to be wrong in different ways. Depending on our expertise, we might take into account the risk that NovS colonies grow on novobiocin agar or fail to grow on plain agar, and how much error our volume measurements have. Bayes' theorem and the associated methods tell us how to revise our original estimate (15% NovR) in the light of the new information (28/386 NovR).
OK, I think this is as far into Bayesian analysis as I want to go. But I'd greatly appreciate comments from readers with more expertise, telling me if what I've written in these three posts is seriously off track.
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Hivestorm1 year ago in Pleiotropy
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The Site is Dead, Long Live the Site1 year ago in Catalogue of Organisms
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The Site is Dead, Long Live the Site1 year ago in Variety of Life
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Does mathematics carry human biases?3 years ago in PLEKTIX
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Daily routine3 years ago in Angry by Choice
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A New Placodont from the Late Triassic of China4 years ago in Chinleana
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Posted: July 22, 2018 at 03:03PM5 years ago in Field Notes
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Bryophyte Herbarium Survey6 years ago in Moss Plants and More
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Harnessing innate immunity to cure HIV7 years ago in Rule of 6ix
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WE MOVED!7 years ago in Games with Words
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post doc job opportunity on ribosome biochemistry!8 years ago in Protein Evolution and Other Musings
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Growing the kidney: re-blogged from Science Bitez8 years ago in The View from a Microbiologist
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Blogging Microbes- Communicating Microbiology to Netizens9 years ago in Memoirs of a Defective Brain
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The Lure of the Obscure? Guest Post by Frank Stahl11 years ago in Sex, Genes & Evolution
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Lab Rat Moving House12 years ago in Life of a Lab Rat
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Goodbye FoS, thanks for all the laughs12 years ago in Disease Prone
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Slideshow of NASA's Stardust-NExT Mission Comet Tempel 1 Flyby12 years ago in The Large Picture Blog
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in The Biology Files
Not your typical science blog, but an 'open science' research blog. Watch me fumbling my way towards understanding how and why bacteria take up DNA, and getting distracted by other cool questions.
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