title: Linguistic diversity and traffic accidents: lessons from statistical studies of cultural traits.
abstract: The recent proliferation of digital databases of cultural and linguistic data, together with new statistical techniques becoming available has lead to a rise in so-called nomothetic studies [1]-[8]. These seek relationships between demographic variables and cultural traits from large, cross-cultural datasets. The insights from these studies are important for understanding how cultural traits evolve. While these studies are fascinating and are good at generating testable hypotheses, they may underestimate the probability of finding spurious correlations between cultural traits. Here we show that this kind of approach can find links between such unlikely cultural traits as traffic accidents, levels of extra-martial sex, political collectivism and linguistic diversity. This suggests that spurious correlations, due to historical descent, geographic diffusion or increased noise-to-signal ratios in large datasets, are much more likely than some studies admit. We suggest some criteria for the evaluation of nomothetic studies and some practical solutions to the problems. Since some of these studies are receiving media attention without a widespread understanding of the complexities of the issue, there is a risk that poorly controlled studies could affect policy. We hope to contribute towards a general skepticism for correlational studies by demonstrating the ease of finding apparently rigorous correlations between cultural traits. Despite this, we see well-controlled nomothetic studies as useful tools for the development of theories.
authors: Seán Roberts Max Plank Institute for Psycholinguistics, Nijmegen, The Netherlands. sean.roberts@mpi.nl
authors: Seán
authors: S
authors: Roberts
authors: James
authors: J
authors: Winters
mesh_terms: D000045:Acacia; D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D003469:Culture; D005114:Extramarital Relations; D063426:Human Migration; D008037:Linguistics / Q000706:statistics & numerical data*; D015233:Models, Statistical; D010802:Phylogeny; D011156:Population Density; D018401:Sample Size; D013223:Statistics as Topic / Q000379:methods*
references: Genome Biol Evol. 2013;5(3):578-90
references: 23431001
references: Nat Rev Neurosci. 2013 May;14(5):365-76
references: 23571845
references: Neuroimage. 2013 Aug 15;77:157-65
references: 23558095
references: Science. 2011 Apr 15;332(6027):346-9
references: 21493858
references: Hypertension. 2012 Sep;60(3):794-801
references: 22892813
references: Science. 2003 Jul 18;301(5631):386-9
references: 12869766
references: Am Econ Rev. 2013 Apr;103(2):690-731
references: 29524925
references: Philos Trans R Soc Lond B Biol Sci. 2011 Feb 12;366(1563):402-11
references: 21199844
references: Nature. 1999 Oct 28;401(6756):877-84
references: 10553904
references: PLoS One. 2010 Jan 20;5(1):e8559
references: 20098492
references: Science. 2009 Jan 23;323(5913):479-83
references: 19164742
references: Science. 2012 Aug 24;337(6097):957-60
references: 22923579
references: Trends Cogn Sci. 2012 Mar;16(3):167-73
references: 22336727
references: J Theor Biol. 2008 Sep 21;254(2):400-7
references: 18599088
references: Sleep Med. 2006 Sep;7(6):508-12
references: 16931152
references: Bioinformatics. 2004 Jan 22;20(2):289-90
references: 14734327
references: Br J Math Stat Psychol. 2013 Feb;66(1):8-38
references: 22364575
references: Proc Natl Acad Sci U S A. 2007 Jun 26;104(26):10944-9
references: 17537923
references: Nat Methods. 2010 Apr;7(4):247-8
references: 20354511
references: Trends Ecol Evol. 2009 Nov;24(11):618-24
references: 19683831
references: J Theor Biol. 2002 Sep 21;218(2):175-85
references: 12381290
references: Conserv Biol. 2010 Aug;24(4):1042-51
references: 20184650
references: Soc Cogn Affect Neurosci. 2010 Jun;5(2-3):203-11
references: 20592043
references: Proc Biol Sci. 2011 Feb 7;278(1704):329-32
references: 20861042
references: N Engl J Med. 2012 Oct 18;367(16):1562-4
references: 23050509
references: PLoS One. 2010 Apr 07;5(4):e10068
references: 20383332
references: Proc Natl Acad Sci U S A. 2007 Jun 26;104(26):10755-6
references: 17581866
references: Nature. 2011 May 5;473(7345):79-82
references: 21490599
references: Nature. 2000 Jun 29;405(6790):1052-5
references: 10890445
references: Proc Biol Sci. 2010 Feb 22;277(1681):529-37
references: 19864286
references: J Exp Psychol Hum Percept Perform. 2013 Oct;39(5):1386-97
references: 23398251