Friday the 13th

reproduced from Aurametrix

Our health depends on a multitude of environmental factors, day in and day out.  And tomorrow is a special day - Friday the 13th.

How should you feel on this day?

Friday the 13th is one of the most feared dates, associated with bad luck in the West. And it is taken cautiously even in cultures that do not fear the 13th - for example, among Chinese mothers avoiding delivering their babies on the 13th.  But science says that those born on the 13th and even those born on Friday the 13th are not in any way less lucky than those born on any other day.

​Yet there were older studies indicating that Friday the 13th might be a bad day to drive (at least, for females), to invest in stocks and to be admitted in hospital. Is it really?  

---

The truth is less people are driving on Friday the 13th (less people are flying too - thus air tickets on this day are always cheaper). And even though according to some data Friday is the most dangerous day to commute to work by car, there is nothing special about traffic accidents on Friday the 13th.

Scientific analysis does not support the belief Friday 13th influence medical emergencies, surgical blood loss and intestinal perforations. Although being hospitalized on Fridays, in general, might be slightly less lucky.

Stocks tend to perform better on Fridays - a phenomenon known as the “weekend effect.”  But many traders refuse to place new trades on Friday 13th. Yet, statistical analysis of trading data over 2 January 1991 to 30 December 2011 suggest that unlucky days (particularly Friday the 13th) generally exhibit higher stock returns. Analysis of FTSE world indices over 1988-2000, for 19 countries - also found that returns on Friday the 13th are statistically different from, and generally greater than, returns on other Friday returns.

The stress of work seems to carry right through until Friday night. But Fridays always generate better moods that peak on Saturdays. So Friday the 13th could be a really good day. And Saturday the 14th might be even better. 

REFERENCES

Fidrmuc, J., & Tena, J. (2015). Friday the 13th: The Empirics of Bad Luck Kyklos, 68 (3), 317-334 DOI: 10.1111/kykl.12085

Lucey, B. (2002). Friday the 13th and the Philosophical Basis of Financial Economics SSRN Electronic Journal DOI: 10.2139/ssrn.962697

Chung, R., Darrat, A., & Li, B. (2014). Superstitions and stock trading: some new evidence Journal of the Asia Pacific Economy, 19 (4), 527-538 DOI: 10.1080/13547860.2014.920589

Stone, A., Schneider, S., & Harter, J. (2012). Day-of-week mood patterns in the United States: On the existence of ‘Blue Monday’, ‘Thank God it's Friday’ and weekend effects The Journal of Positive Psychology, 7 (4), 306-314 DOI: 10.1080/17439760.2012.691980

Smyth JM, Wonderlich SA, Sliwinski MJ, Crosby RD, Engel SG, Mitchell JE, & Calogero RM (2009). Ecological momentary assessment of affect, stress, and binge-purge behaviors: day of week and time of day effects in the natural environment. The International journal of eating disorders, 42 (5), 429-36 PMID: 19115371

Schuld J, Slotta JE, Schuld S, Kollmar O, Schilling MK, & Richter S (2011). Popular belief meets surgical reality: impact of lunar phases, Friday the 13th and zodiac signs on emergency operations and intraoperative blood loss. World journal of surgery, 35 (9), 1945-9 PMID: 21713579

Almond D, Chee CP, Sviatschi MM, & Zhong N (2015). Auspicious birth dates among Chinese in California. Economics and human biology, 18, 153-9 PMID: 26160600