Hitchhikers' smiles and receipt of help.

The positive association of smiling on helping behavior is well established in social psychology. Nevertheless, no study was found for the effect of smiling on hitchhiking success. An experiment was carried out in France where hitchhiking is a legal and common practice. Four confederates, 2 young men and 2 young women, selected for their "average attractiveness" hitchhiked, signaled to 800 (503 men and 297 women) motorists driving along the road on a peninsula. In half of the cases, the confederate smiled at the motorist. Analysis showed that, when hitchhiking women were smiling, motorists stopped more frequently but not when hitchhikers were men. Also, in all conditions, motorists who stopped were male.