a big punch to Behavioural Recommender Systems

These new papers are a big punch to Behavioural Recommender Systems / Recommendation Engines for Online Dating sites, like the ones used at Match or PlentyOfFish:

"Perceptions of Ideal and Former Partners' Personality and Similarity"
Pieternel Dijkstra / Dick P. H. Barelds / University of Groningen, The Netherlands

Abstract
The present study aimed to test predictions based on both the 'similarity-attraction' hypothesis and the 'attraction-similarity' hypothesis, by studying perceptions of ideal and former partners. Based on the 'similarity-attraction' hypothesis, we expected individuals to desire ideal partners who are similar to the self in personality. In addition, based on the 'attraction-similarity' hypothesis, we expected individuals to perceive former partners as dissimilar to them in terms of personality. Findings showed that, whereas the ideal partner was seen as similar to and more positive than the self, the former partner was seen as dissimilar to and more negative than the self. In addition, our study showed that individuals did not rate similarity in personality as very important when seeking a mate. Our findings may help understand why so many relationships end in divorce due to mismatches in personality.

Method
Participants and procedure
Participants were 871 (612 women, 259 men) members of two dating sites, one for college-educated singles under fifty looking for a long-term mate (match4me.nl; n = 421) and one for singles over fifty looking for a long-term mate (50plusmatch.nl; n = 450). Mean age was 50.18 years (SD = 11.32, range 19-78).

Measures
Personality. Personality characteristics were assessed by an abridged version of Shafer's 30-item bipolar rating scale designed to measure the Five-Factor Model of personality.
The participants answered the personality items three times in total, thus providing self-ratings, ratings of their ideal partner and ratings of their former partner.

Discussion
Our findings strongly support the 'similarity-attraction' hypothesis: Individuals clearly desire a potential partner with a similar personality.
In addition to finding a mate with a similar personality, our study showed that individuals seek a mate who is slightly 'better' than they are: They prefer a mate who is somewhat less neurotic, more agreeable, more conscientious, more open and more extraverted than they are themselves.
.... mismatches in personality are a frequently mentioned cause for relationship break-up. If former partners indeed have dissimilar personalities, our findings underline how difficult it is for many people to select a mate with a similar personality, or, alternatively, how little value individuals put on finding a similar partner in terms of personality.

The present study's results, as well as the results found in previous studies (e.g., Eastwick & Finkel, 2008), may be used to educate people, especially singles, about what really matters in long-term relationships, for instance, similarity in personality, instead of complementarity.


"An assessment of positive illusions of the physical attractiveness of romantic partners"
Dick P. H. Barelds, Pieternel Dijkstra, Namkje Koudenburg and Viren Swami

Abstract
Positive illusions about a partner's physical attractiveness occur when individuals' ratings of their partner's attractiveness are more positive than more objective ratings. Ratings that may serve as a 'reality benchmark' include ratings by the partner him/herself and observer ratings. The present study compared the effects of using different reality benchmarks on the strength of positive partner physical attractiveness illusions (n = 70 couples). Results showed that individuals positively biased both their own and their partner's physical attractiveness. As a consequence, using a partner's self-ratings as a reality benchmark results in an underestimation of positive illusions. Presenting participants with photographs had a small effect on physical attractiveness ratings provided by women, showing that photographs, to some extent, might constrain positive illusions.


----------------
Do you see how Latest Research in Theories of Romantic Relationships Development shows: compatibility is all about a high level on personality* similarity* between prospective mates for long term mating with commitment?
*personality measured with a normative test.
*similarity: there are different ways to calculate similarity, it depends on how mathematically is defined.

Also several studies showing contraceptive pills users make different mate choices, on average, compared to non-users and people often report partner preferences that are not compatible with their choices in real life [uncovered by Eastwick & Finkel (2008); Kurzban & Weeden (2007); Todd, Penke, Fasolo, & Lenton (2007)].