Relationship between breast size and size of tips

While conducting some research for my forthcoming trade book tentatively titled The Consuming Instinct: What Juicy Burgers, Ferraris, Pornography, and Gift Giving Reveal About Human Nature (Prometheus Books, 2011), I came across a study authored by Nicolas Guéguen on the likelihood of a female hitchhiker being picked up, by either a male or female driver, as a function of her breast size. On a related note, some of you might recall my recent post on the positive correlation between waitresses' tips and their breast size.

 
In visiting Nicolas Guéguen's website, I could not help but notice that he possesses a talent for conducting naturalistic experiments about issues that many people have wondered about and yet few (if any) have tested. Recall my earlier post on the likelihood of a woman being approached at a bar as a function of whether she is wearing cosmetics (one of Guéguen's other papers).
 
Returning to the current paper, Guéguen created one of three naturalistic experimental conditions (corresponding to three breast sizes) using an average looking female confederate: (1) her actual breast size, which was an A cup (i.e., smaller than the French average); (2) a B cup (the average size in France); (3) a C cup (greater than the average). The breast "augmentations" were performed via the addition of a latex implant.


 
The female confederate then stood at the side of a road and actually hitch hiked (i.e., put out her thumb as cars whizzed by). Two observers coded the number of male and female drivers that drove by along with the number of times that a given driver stopped to pick up the confederate. For obvious security reasons, once a driver stopped, this was counted as an instance of having picked up the hitchhiker. In other words, the confederate did not actually get into any cars. A male observer also hid close by to ensure against any possible threats to the confederate's security.
                                      Cup Size A          Cup Size B          Cup Size C

Male drivers (n = 774)       40/268                 46/256                  60/250 

                                        (14.92%)              (17.79%)               (24.00%)

Female drivers (n = 426)  12/132                 11/144                   14/150 


                                         (9.09%)                (7.64%)                 (9.33%)

Statistically speaking, only men's behaviors were affected by the hitchhiker's breast size (p < .03). The frequency of stopping in the cup C condition was marginally greater than that of cup B (p = 0.09) and significantly greater than that of cup A (p < .01). The difference between cups A and B was not significant.
 

The bottom line: If a woman has large breasts, men are more likely to engage in prosocial behavior (in this case offering her a ride). I suppose that we could have all predicted this fact albeit it is fun to see it tested in a scientific manner. Finally, I am only the messenger so direct your accusations of patriarchal oppression to Dr. Guéguen!


My fellow PT blogger Christopher Ryan recently put up a post explaining the allure of breasts. As he correctly explained, there are several evolutionary explanations for men's visual intoxication with breasts. In today's post, I'd like to discuss a consequence of this attraction within the service industry.
 
Michael Lynn is a professor of consumer behavior and marketing at the Cornell University School of Hotel Administration, and perhaps the most eminent researcher on tipping behavior. He has explored numerous variables that affect the size of tips left by patrons. 

In a recent study published in the Archives of Sexual Behavior, Professor Lynn found a positive correlation between the breast size of waitresses (n = 432) and the size of their tips (both were self-reported measures). He did not split the tipping data by sex of the patrons. One might expect that the "breast effect" might enhance tips for male patrons whereas female patrons might "punish" shapely waitresses (intra-sexual rivalry). 
 
The existing data did not allow for a more refined set of analyses to test such possibilities. Also, Lynn notes that he might have expected a quadratic relationship between breast size and size of tips, namely, breasts that are too small or too big would result in lower tips than medium sized breasts. However, his data suggests that bigger is always better...at least when it comes to tipping behavior!