The Köhler effect

August 12, 2012

Start of 4×100m relay, 2008 Olympics (photo: “Jmex60”)

In line with the current Olympic fever, a recent article in Wired magazine discusses the Köhler effect in relay races. The Köhler effect (see Hertel et al. 2000 and Kerr et al. 2005) is a phenomenon where less capable members of a team are motivated to perform at a higher level so as to “keep up” with their team-mates (some degree of feedback on performance is required).

A recent journal article cited by Wired studied collegiate swim and high-school track & field relays, and showed a significant Köhler effect, especially in finals. Kerr has also demonstrated the effect in other kinds of collaborative activity.

The lesson here is: to produce a truly stellar team, motivate the weaker members to “keep up,” show them how, and provide objective feedback on how well they are doing.

Members of Cassini spacecraft imaging team, crossing Abbey road (photo:

– Tony

Citius, Altius, Fortius

August 10, 2012

Given the current Olympic fever, it’s interesting to look at the rate at which countries win medals. Tiny Grenada managed a gold, while Jamaica and New Zealand managed more than 2 medals per million head of population:

Rank Country Medals Medals per million
1 Grenada (GRD) 1 9.5
2 Jamaica (JAM) 9 3.3
3 New Zealand (NZL) 10 2.3
4 Slovenia (SVN) 4 1.9
5 Denmark (DNK) 9 1.6
6 Estonia (EST) 2 1.5
7 Hungary (HUN) 15 1.5
8 Australia (AUS) 29 1.3

Some of those countries are too small to see on this map, but the “third rung” with between 1 and 2 medals per million – Slovenia (SVN), Denmark (DNK), Estonia (EST), Hungary (HUN), Australia (AUS), Cyprus (CYP), Qatar (QAT), Belarus (BLR), and Mongolia (MNG) – mostly stand out:

Medals per million at London, so far (click to zoom)

What makes those countries produce so many athletes running faster, jumping higher, and enduring longer? It’s not national wealth, as the graph below shows. Partly, it’s quality coaching. But most of all, “there is no gene for the human spirit.”

– Tony