Wikipedia:Reference desk/Archives/Science/2015 July 20

= July 20 =

What's the formula that predicts telephonic traffic? Is there one for humans instead of phone calls?
I saw in a math book long ago that there's a formula that predicts phone traffic between US city pairs by population and distance and people hardly ever called from Seattle to Miami compared to between Baltimore and DC or something because it's exponential or something with distance. I wonder what it was. Maybe there's one for transportation of humans or even Internet traffic? Sagittarian Milky Way (talk) 01:20, 20 July 2015 (UTC)


 * Teletraffic engineering involves much math, but particular city pair predictions, whether for telegrams or airline flights, are mostly based on recent traffic, with the predicting part being mainly guessing at future growth rates. Jim.henderson (talk) 01:49, 20 July 2015 (UTC)


 * Well I'm sure actual data would be more accurate but there's got to be a formula that fits the data points closest. Also, few people would get to the airport 2 hours before to fly a short distance so adding highway traffic would probably make a better formula (though one fit for airlines might fit well for long distances). Sagittarian Milky Way (talk) 02:05, 20 July 2015 (UTC)


 * Yes, IIRC this formula was important in a wider scope than just telephony. You might get a better response at Computing or Mathematics. μηδείς (talk) 16:00, 20 July 2015 (UTC)


 * Public events like cricket (FIFA World Cup) or similar events on TV may cause phone usage behavior like no calls and many calls in the break, advertising gaps and when a team has won. -- Hans Haase (有问题吗) 20:15, 20 July 2015 (UTC)

Coronal sulcus and foreskin of penis
Why is it that some normal foreskins retract over the head and past the coronal sulcus and others only go over the head but not past the sulcus? What determines how far down the foreskin goes and why is it different for different people? 94.14.154.30 (talk) 20:57, 20 July 2015 (UTC)


 * Human_variability. SemanticMantis (talk) 21:14, 20 July 2015 (UTC)
 * For the last question, see Frenulum_of_prepuce_of_penis. SemanticMantis (talk) 22:39, 20 July 2015 (UTC)
 * As an uncircumcised male, I challenge the premise that any healthy adult male can not retract their foreskin past the coronal calculus. I think it's borderline a medical condition if you can't do that after puberty, but it's not really something I want to search for references on this comptuer. Vespine (talk) 22:51, 20 July 2015 (UTC)
 * I guess it depends on what is considered "healthy" - phimosis is a real thing, not clear to me that that in and of itself is an illness. From the article "Normal developmental non-retractability does not cause any problems. Phimosis is deemed pathological when it causes problems" (emphasis mine). SemanticMantis (talk) 23:08, 20 July 2015 (UTC)
 * So it's not a problem unless it's a problem? :) Sounds like an argument for circumcision. ←Baseball Bugs What's up, Doc? carrots→ 03:22, 21 July 2015 (UTC)
 * Your leg is not a problem until it is a problem? Sounds like an argument for amputation. Fgf10 (talk) 11:31, 21 July 2015 (UTC)
 * Could be! ←Baseball Bugs What's up, Doc? carrots→ 13:54, 21 July 2015 (UTC)
 * If it wont go, it needs stretching -- continually!!--81.147.170.83 (talk) 15:26, 21 July 2015 (UTC)
 * Possibly aided by a motor, such as the Wankel engine. ←Baseball Bugs What's up, Doc? carrots→ 00:40, 22 July 2015 (UTC)
 * There could be a number of drawbacks with that approach!--81.147.170.83 (talk) 20:03, 22 July 2015 (UTC)