significance tests

S. Senn: Testing Times (Guest post)



Stephen Senn
Consultant Statistician
Edinburgh, Scotland

Testing Times

Screening for attention

There has been much comment on Twitter and other social media about testing for coronavirus and the relationship between a test being positive and the person tested having been infected. Some primitive form of Bayesian reasoning is often used  to justify concern that an apparent positive may actually be falsely so, with specificity and sensitivity taking the roles of likelihoods and prevalence that of a prior distribution. This way of looking at testing dates back at least to a paper of 1959 by Ledley and Lusted[1]. However, as others[2, 3] have pointed out, there is a trap for the unwary in this, in that it is implicitly assumed that specificity and sensitivity are constant values unaffected by prevalence and it is far from obvious that this should be the case. Continue reading

Categories: S. Senn, significance tests, Testing Assumptions | 14 Comments

August 6: JSM 2020 Panel on P-values & “Statistical Significance”


July 30 PRACTICE VIDEO for JSM talk (All materials for Practice JSM session here)

JSM 2020 Panel Flyer (PDF)
JSM online program w/panel abstract & information):

Categories: ASA Guide to P-values, Error Statistics, evidence-based policy, JSM 2020, P-values, Philosophy of Statistics, science communication, significance tests | 3 Comments

JSM 2020 Panel on P-values & “Statistical Significance”

All: On July 30 (10am EST) I will give a virtual version of my JSM presentation, remotely like the one I will actually give on Aug 6 at the JSM. Co-panelist Stan Young may as well. One of our surprise guests tomorrow (not at the JSM) will be Yoav Benjamini!  If you’re interested in attending our July 30 practice session* please follow the directions here. Background items for this session are in the “readings” and “memos” of session 5.

*unless you’re already on our LSE Phil500 list

JSM 2020 Panel Flyer (PDF)
JSM online program w/panel abstract & information): Continue reading

Categories: Announcement, JSM 2020, significance tests, stat wars and their casualties | Leave a comment

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