Archive for leap year
Bayesian score calibration at One World ABC’minar [only comes every 1462 days]
Posted in Books, Statistics, University life with tags ABC, Approximate Bayesian computation, approximate Bayesian inference, approximate models, Bayesian calibration, IMS, leap year, One World ABC Seminar, seminar, University of Warwick, webinar on February 22, 2024 by xi'an
optimal leap year
Posted in Books, Kids, Mountains, pictures, R with tags Australia, daylight saving time, Gregorian calendar, Kata Tjuta, leap year, Mounts Olga, R, sunset on November 19, 2022 by xi'an
A riddle about leap years: a solar year consists of approximately 365.24217 mean solar days, which is why there is a leap year approximately every four years. Approximately because the Gregorian calendar plans 97 and not 100 leap years over 400 years. Is this the optimal solution? No, since the Gregorian difference is 3.3 10⁻⁴ day per year, or 0.132 day per 400 years, while using 85 leap years over every 351 years leads to a difference of 4.76 10⁻⁶ day per year, or 0.002 day per 400 years… (With a further gain by a factor 4 with 116 leap years every 479 years.) This can be found by a basic R code
for(N in 10:1000)
for(L in 1:N){
p=abs(L/N-.24217)
if(p<T){T=p;lo=L;no=N}}
