Wednesday, December 29, 2010

You and your friends have very similar minds / FACEBOOK

You and your friends have very similar minds
"The word 'homophily' literally means 'love of the same'. It is the idea that people tend to associate with others similar to them"

That research of "Birds of a Feather Flock Together" is also consistent with the 3 milestone discoveries of the 2001 - 2010 decade for Theories of Romantic Relationships Development.

Thursday, December 23, 2010

The 3 milestone discoveries of this decade.

The 2001 - 2010 decade will end soon.

Only 3 major discoveries can help to revolutionize the online dating industry.
Major online dating sites can not ignore them any more, or they will die instead.

I) Several studies showing contraceptive pills users make different mate choices, on average, compared to non-users.

I.1) "Human oestrus" Gangestad & Thornhill (2008)
"Only short-term but not long-term partner preferences tend to vary with the menstrual cycle"

I.2) "Does the contraceptive pill alter mate choice in humans?" Alvergne & Lummaa (2009)
".. whereas normally cycling women express a preference for MHC (Major Histocompatibility Complex) dissimilarity in mates, pill users prefer odours of MHC-SIMILAR men, indicating that pill use might eliminate adaptive preferences for genetic dissimilarity."

I.3) "Personality and reproductive success in a high-fertility human population"  Alvergne, Jokelac & Lummaaa (2010)
The reproductive success of both men and women is influenced by our personality traits, according to the paper.
The study, found that women with higher levels of neuroticism and more extravert men, are likely to give birth to a larger number of children in societies with traditionally high birth rates.

---------------------------------------------------

II) 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)]

II.1) "Do People Know What They Want: A Similar or Complementary Partner?" Barelds & Dijkstra (2008)

II.2) Also reported in "What lies beneath: The linguistic traces of deception in online dating profiles." Toma & Hancock (2010)
That paper investigates whether deceptions in online dating profiles correlate with changes in the way daters write about themselves in the open-ended portion of the profile, and whether those changes are detectable by either computerized linguistic analyses or human judges.

---------------------------------------------------
III) The strict personality similarity axis.

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 Personality Based Recommender Systems are the next generation of recommender systems because they perform FAR better than Behavioural ones (past actions and pattern of personal preferences)
That is the only way to improve recommender systems, to include the personality traits
of their users and they need to calculate personality similarity between them.

------------------------------------------
The entire Online Dating Industry for serious daters in 1st World Countries has:
* No Legislation.
* No Quality Norms.
* Low reliable background checks.

The entire Online Dating Industry for serious daters in 1st World Countries is a HOAX, performing as a Big Online Casino, with a low effectiveness/efficiency level of their matching algorithms (less than 10%),

There is a range convergence phenomenon between the 3 mains tools online dating sites offer now: Searching by your own, Recommendation Engines and Compatibility Matching Methods based on proprietary models or the Big5. Any member receives on average 3 to 4 prospective mates as selected / recommended / compatible for dating purposes per 1,000 members screened in the database.
They all 3 are performing the same for serious daters, with a high percentage of false positives, like gun machines firing flowers.

The Online Dating Industry needs innovations, but the innovations the Online Dating Industry needs will come from only one source: the latest discoveries in theories of romantic relationships development with commitment.

WorldWide, there are over 5,000 online dating sites
but no one is using the 16PF5 (or similar test) to assess personality of its members.
Without offering the 16PF5 (or similar test measuring exactly the 16 personality factors) for serious dating, it will be impossible to innovate and revolutionize the Online Dating Industry.

Paper about 2D:4D finger-length ratio

PAPER: "Short- and Long-Term Relationship Orientation and 2D:4D finger-length ratio."

Study 1 explored the relationships between 2D:4D finger length ratio and Relationship Orientation (Short- and Long-Term Relationship Orientation) in a sample of men. 


Study 2 extended Study 1, examining both sexes and further variables which might influence Short- and Long-Term Relationship Orientation. Earlier studies found different correlations between 2D:4D and the construct of interest, depending on the hand (left or right) and sex of the participants. Therefore, we report our correlations between 2D:4D and Short- and Long-Term Relationship Orientation for both hands separately.

(mistakes at Fig 1. and Fig 2., the right part of figures relates to left hand)

That paper does not assess personality of participants and does not take into account actual facts like:
* contraceptive pills / contraceptive hormonal treatments
* women who work and earn more money than men.

That paper also does not cite fresh, new & important studies showing contraceptive pills users make different mate choices, on average, compared to non-users.

1) "Human oestrus" Gangestad & Thornhill (2008)
"Only short-term but not long-term partner preferences tend to vary with the menstrual cycle"

2) "Does the contraceptive pill alter mate choice in humans?" Alvergne & Lummaa (2009)
".. whereas normally cycling women express a preference for MHC (Major Histocompatibility Complex) dissimilarity in mates, pill users prefer odours of MHC-SIMILAR men, indicating that pill use might eliminate adaptive preferences for genetic dissimilarity."

3) "Personality and reproductive success in a high-fertility human population"  Alvergne, Jokelac & Lummaaa (2010)
The reproductive success of both men and women is influenced by our personality traits, according to the paper.
The study, found that women with higher levels of neuroticism and more extravert men, are likely to give birth to a larger number of children in societies with traditionally high birth rates.



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.

Monday, December 20, 2010

Dannon's Activia, DanActive health claims draw USD21M fine.


Dannon in USA — part of the world's biggest yogurt maker Danone— agreed to pay a USD21 million fine and stop making exaggerated health claims for two popular Dannon products under a settlement with the federal government and attorneys general from 39 states on Wednesday 15th.

It follows Monday's USD2.1 million FTC settlement with kids-vitamin maker NBTY over unsupported health claims and because the products didn't have the amount of omega-3 claimed.

The government says Dannon will stop claiming that one daily serving of Activia yogurt relieves irregularity and that DanActive helps people avoid catching colds.

"These types of misleading claims are enough to give consumers indigestion," FTC Chairman Jon Leibowitz says. "Companies like Dannon shouldn't exaggerate the strength of scientific support."


Exactly the same should be applied for the Online Dating Industry: eHarmony, Chemistry, PerfectMatch, PlentyOfFishMarriagePredictor, MeeticAffinity, Parship, Be2, and others.

See the article:

"The horse named Jim in the Online Dating Industry"

Saturday, December 18, 2010

Chemistry, 6 years from its genesis.

Six long years ago, during December 2004, Dr. Helen Fisher was contacted by the people from Match to create Chemistry, the last innovation at Match, a compatibility matching method.

Up to now, she had published 2 posters and 1 paper.

Interesting to read them, although she CAN NOT prove her matching algorithm, used at Chemistry, can match prospective partners who will have more stable and satisfying relationships than couples matched by chance, astrological destiny, personal preferences, searching on one's own, or other technique as the control group in a peer_reviewed Scientific Paper.


POSTER "Four Primary Temperament Dimensions Based on Neurochemistry"

Personality is composed of two basic types of traits:
traits that an individual acquires, dimensions of character;
and
traits with biological underpinnings, dimensions of temperament (Cloninger 1987).

Temperament is mediated by many factors and can be only indirectly associated with neurochemical data.
Data were collected on all four scales on an Internet dating site (Chemistry), regularly between 2006-2007 until reliability was obtained in a United States sample of 39,913 anonymous men and women.
Participants completed demographic information, the Fisher-Rich-Island Neurochemical Questionnaire (FRI-NQ), and validity questions, with the goal of finding a romantic partner.  Respondents ranged in age from 18 to 88 years (M = 37.0; SD= 12.6); 56.4% were female (N = 22,521); 89.6% (N = 35,759) were seeking an opposite-sex partner; and 45.2% (N = 18,035) had children. 
The FRI-NQ measure was placed on an international dating site in 39 other countries, beginning in January 2008, and data to measure reliability were collected on 15,000 individuals in each of these translations: German, French, Spanish, English (Australian sample), and Swedish.  
All individuals expressed all four temperament dimensions; yet individuals varied in the degree to which they expressed each.
* Dopamine and Norepinephrine (DA/NE)
* Serotonin (5-HT)
* Testosterone (T)
* Estrogen and Oxytocin (E/OT)
As predicted, men and participants who reported their occupation as engineering scored higher on the proposed T scale, women and participants who indicated they were teachers scored higher on E/OT.  On the proposed 5HT scale, persons reporting a religious affiliation obtained the highest mean score, followed by persons describing themselves as 'spiritual but not religious', with the lowest scores obtained by those describing themselves as agnostics or atheists.  Persons describing their friends as 'Adventurous' tended to score higher on the proposed DA/NE scale.




POSTER "Four Primary Temperament Dimensions in the Process of Mate Choice"
The purpose of this investigation was to examine the role of temperament in the INITIAL attraction phase of mate choice.
Cross-cultural surveys, brain imaging studies, population and molecular genetics, comparative research and twin studies suggest that many traits of temperament are heritable, relatively stable across the life course and linked to specific gene pathways and/or hormone or neurotransmitter systems. 
Participants from the online website Chemistry who provided consent for inclusion in research were selected for this study. The final sample comprised 28,128 male (n=17,776) and female (n=10,352) heterosexual adults, who provided data on their selections for a first meeting with a potential romantic partner and who gave a non-negative (positive or blank) rating of their partner after returning from the first date were selected for the analysis.
A 56-item temperament measure, the Fisher-Rich-Island Neurochemical Questionnaire (FRI-NQ) was used to assess compatibility between participants.
Participants were anonymous adults who regularly used Chemistry dating site between 2006-2007 for the purpose of finding a romantic partner. Participants were selected based on their research consent and the release of their SELF-REPORTED demographic, dating, and personality data.  The final scales were VALIDATED on a sample of 39,913 participants from this dating site.
Similarity attracted among those predominantly expressive of the proposed  dopamine/norepinphrine and serotonin scales; while opposites attracted among those predominantly expressive of the proposed testosterone and estrogen/oxytocin scales. 
A study of long term married opposite-sex couples is currently underway to assess the durability of initial biological attraction.

Also Dr. Heidi Island from Pacific University is preparing the paper:
"Temperament as a Mechanism for Mate Choice: an hypothesis and pilot study."



PAPER "The Second to Fourth Digit Ratio: A Measure of Two Hormonally-based Temperament Dimensions"
"Individuals who reported a longer 4th finger relative to 2nd expressed high scores on the proposed testosterone scale; individuals who reported a longer 2nd finger relative to 4th or 2nd and 4th digits of equal length expressed high scores on the proposed estrogen/oxytocin scale."



 









---------------------------

Please remember personality = temperament + character
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.
*Although no actual fresh paper uses the 16PF normative personality test (they mostly use different versions of the normative Big5 personality test instead) and linear or logistic multivariate regression equations to calculate similarity, they clearly show a connection between personality similarity and marital happiness / dyadic success (stability and satisfaction) for some persons.
**Similarity is a word that has different meanings for different persons or companies, it exactly depends on how mathematically is defined.



Also there is a similarity trilogy between genetic, mate choice and personality based recommender systems.
 

Thursday, December 16, 2010

The Scramjet (supersonic combustion ramjet) engine

Sometimes I read posts about a "fairly complex matching algorithm" for online dating
or
receive emails promoting "a sophisticated algorithm" and then I laugh!!!
Matching algorithms do not need to be complex or sophisticated, they need to be effective.
From Merriam-Webster Dictionay:
effective (Synonyms: effectual, efficacious, efficient, fruitful, operative, potent, productive):
a : producing a decided, decisive, or desired effect.

Those complex or sophisticated matching algorithms are like the Wright R-3350 Duplex-Cyclone used in the Boeing B-29 Superfortress, useless at all to ....... break sound barrier!!!

LIFEPROJECT METHOD is so simple!
It is only strict personality similarity. A Scramjet engine.
Read Innovations: to take the 16PF5 test 3 times.

As for a comparison, please see the following articles
The Wright R-3350 Duplex-Cyclone used in the Boeing B-29 Superfortress
The Wright R-3350 Duplex-Cyclone was one of the most powerful radial aircraft engines produced in the United States, useless at all to break sound barrier!

Jet Engine
and
the Scramjet (supersonic combustion ramjet)



The Meetic Group is slowly collapsing.

The Meetic Group is slowly collapsing.


In the same road as Be2

I am featured in the Latest Mobile Social Web 2.0 Forecasts, Challenges & Regulations 2010-2014 from Juniper Research, where I said "Perhaps by 2014, the mobile concept will be diluted (or disappear) for dating purposes with the majority of subscribers using netbooks/iPads with mobile broadband modems, or WiFi, rather than smartphones".

Monday, December 13, 2010

Quality Norms

Shaadi, the only one with ISO 9001:2008 Quality Norms for Customer Care and Support Functions




Why others like eHarmony - Match / Chemistry cannot certify?

Friday, December 10, 2010

Seasonality and Personality

Seasonality and Personality

If you had read

"Babies' biological clocks dramatically affected by birth light cycle" where it says

"Seasonality and Personality

The new study raises an intriguing but highly speculative possibility: Seasonal variations in the day/night cycle that individuals experience as their brains are developing may affect their personality."


I had read the brief communication "Perinatal photoperiod imprints the circadian clock" and the word "personality" is not mentioned there.



I had also contacted Dr. McMahon to ask him if he could quantify / estimate the % of the contribution of "Seasonality" to personality development in humans.

He had answered: "In answer to your inquiry - It is not possible to quantify any possible effect in humans. This is an idea that still must be tested."

Wednesday, December 8, 2010

Online Dating Industry 2011, predictions

Main prediction for the Online Dating Industry 2011: The Online Dating Fatigue Phenomenon will get even worse during 2011.


PlentyOfFish had reached operating ceiling, now decaying. eVow can not take off

eHarmony USA losing traffic. You will see daters leaving in droves from old paid sites like Match, Chemistry, True, eHarmony, PerfectMatch, Be2, Parship, Meetic, etc.

MySpace is going to be the biggest dating application for fun, in ... Facebook!!!
MySpace NOW is a deliberately social dating site; for fun, for entertainment purposes, for instant gratification but nor for serious dating with commitment.
It is clearly a threat to all dating applications at Facebook and PlentyOfFish / OKCupid.



Mr. Greg Blatt named CEO of IAC? He is only a lawyer. He is not going to innovate in nothing.
My bet: He will continue to acquire rotten tech companies in order to show some kind of success, show achievements, show milestones during his tenure.

The entire Online Dating Industry for serious daters in 1st World Countries has:
* No Legislation.
* No Quality Norms.
* Low reliable background checks.

The entire Online Dating Industry
for serious daters in 1st World Countries is a HOAX, performing as a Big Online Casino, with a low effectiveness/efficiency level of their matching algorithms (less than 10%),

There is a range convergence phenomenon between the 3 mains tools online dating sites offer now: Searching by your own, Recommendation Engines and Compatibility Matching Methods based on proprietary models or the Big5. Any member receives on average 3 to 4 prospective mates as selected / recommended / compatible for dating purposes per 1,000 members screened in the database.
They all 3 are performing the same for serious daters, with a high percentage of false positives, like gun machines firing flowers.

The Online Dating Industry needs innovations, but the innovations the Online Dating Industry needs will come from only one source: the latest discoveries in theories of romantic relationships development with commitment.

WorldWide, there are over 5,000 online dating sites
but no one is using the 16PF5 (or similar test) to assess personality of its members.
Without offering the 16PF5 (or similar test measuring exactly the 16 personality factors) for serious dating, it will be impossible to innovate and revolutionize the Online Dating Industry.













MySpace a social dating site



MySpace NOW is a deliberately social dating site; for fun, for entertainment purposes, for instant gratification but nor for serious dating with commitment.
It is clearly a threat to all dating applications at Facebook and PlentyOfFish / OKCupid.

Thursday, December 2, 2010

Match Japan / brief review

eHarmony plans to enter the Japanese market, Match has its Japanese version since 2002.
Match Japan is like Match Venus or Match Mars or Match in the Moon.
Very few Japanese are using Match (it also includes Chemistry as well, optative)
You can check traffic and rank from Alexa, it is not an independent domain name, it is the subdomain
www.JP.match.com

Match's Worldwide Traffic Rank = Japan 1,810, it means does not exist.
Where Visitors Go on Match = 2.5% of Site Traffic go to www.JP.match.com


Remember, Dec 27, 2006 interview at Online Personals Watch, the former CEO of Match had said:
".. a matchmaker for Match Platinum.... ..We'll also be piloting this in several international markets as well, specifically Japan and the UK. " but Match can never exploit the Japanese Market.

Match Japan is like a flag in the Moon.

Yahoo Babel Fish translates far better than Google Translate.
Check both translations from Japanese to English.



The homepage shows you a link to the last event, the Feb 9th 2010 Valentine Day!!!



The profiles are quite similar to the USA site, but the Japanese can add up to 7 certificates to increase reliability of their profiles.
like
Human proof: a copy of driver's license, health insurance, passports.
Address proof: inhabitant vote, invoices from different services.
Working proof: Employee proof
Earnings proof: The withholding certificate which can prove the earnings of the preceding year, the final return, either one of the certificates for paid taxes.
Graduation proof: Diploma or graduation certificate.
Celibacy proof: The celibacy certificate from certificate for marriage information service / marriage consultation trader.
Credit card proof: When charge service of match is purchased (purchase with credit card certification), credit card proof becomes effective.



My computer does not have the Japanese fonts installed, anyway I do not understand Japanese.



Wednesday, December 1, 2010

eHarmony Japan?



eHarmony Japan?

I used Google Translate to know it says the site will be launched soon.

The Big 5 is good for orientative purposes but not good enough for predictive purposes, it will "see" all Japanese women/men as all the same.

You can read:
"PATTERNS AND UNIVERSALS OF ADULT ROMANTIC ATTACHMENT ACROSS 62 CULTURAL REGIONS Are Models of Self and of Other Pancultural Constructs?"
JOURNAL OF CROSS-CULTURAL PSYCHOLOGY, Vol. 35 No. 4, July 2004 367-402

"Analyses of specific attachment styles revealed that secure romantic attachment was normative in 79% of cultures and that preoccupied romantic attachment was particularly prevalent in East Asian cultures."

Tuesday, November 30, 2010

eHarmony Brazil 3 months

eHarmony Brazil, a 3 months old site, can not take off, slowly dying. The summer will begin soon here in South America (also in Australia).

Wednesday, November 24, 2010

summary of recommender systems

Recommender systems (a.k.a recommendation engines) can be based on:

- past actions (as the formely Beacon at Facebook)

- a pattern of personal preferences (by collaborative filtering, as the actual one at Facebook) The main disadvantage with recommendation engines based on collaborative filtering is when users instead of providing their personal preference try to guess the global preference and they introduce bias in the recommendation algorithm.

- personality traits of users.

Personality Based Recommender Systems are the next generation of recommender systems because they perform FAR better than Behavioural ones (past actions and pattern of personal preferences)
That is the only way to improve recommender systems, to include the personality traits of their users.
Have you seen they need to calculate personality similarity between users?
Have you seen there are different formulas to calculate similarity?
In case you did not notice, recommender systems are morphing to .......... compatibility matching engines!!!
They mostly use the Big5 to assess personality and the Pearson correlation coefficient to calculate similarity.
Researchers in the Personality Based Recommender Systems arena are also testing different / novel formulas to calculate similarity, useless at all because they use the Big5 to assess personality of users.

That is nothing new, nothing innovative. Online Dating Sites like eHarmony, Parship, Be2, MeeticAffinity and others had been calculating personality similarity between prospective users since several years ago with low successful rates, with a low effectiveness/efficiency level of their matching algorithms (less than 10%) because they use the normative Big5 or ipsative proprietary models instead -like Chemistry or PerfectMatch- to measure personality traits.

No one is using the 16PF5 to assess personality of members.
No one calculates similarity with a quantized pattern comparison method.
No one can show Compatibility Distribution Curves to each and every of its members.

Psychological-based Recommenders Systems


More about Personality-based Recommender Systems

The NEW era of Personality Based Recommender Systems

Personality Based Recommender Systems

The PLAGUE of recommender systems

Recommender Systems and the Social Web


A Novel K-Means Based Clustering Algorithm for High Dimensional Data Sets

Recommender System for Online Dating Service

Tuesday, November 23, 2010

Predicting relationship and life satisfaction from personality

"Predicting relationship and life satisfaction from personality in nationally representative samples from three countries: the relative importance of actor, partner, and similarity effects."


Abstract
Three very large, nationally representative samples of married couples were used to examine the relative importance of 3 types of personality effects on relationship and life satisfaction: actor effects, partner effects, and similarity effects. Using data sets from Australia (N = 5,278), the United Kingdom (N = 6,554), and Germany (N = 11,418) provided an opportunity to test whether effects replicated across samples. Actor effects accounted for approximately 6% of the variance in relationship satisfaction and between 10% and 15% of the variance in life satisfaction. Partner effects (which were largest for Agreeableness, Conscientiousness, and Emotional Stability) accounted for between 1% and 3% of the variance in relationship satisfaction and between 1% and 2% of the variance in life satisfaction. Couple similarity consistently explained less than .5% of the variance in life and relationship satisfaction after controlling for actor and partner effects.



That research has 2 weak points:

1) The Big 5 test to assess personality of spouses. The Big 5 test is an oversimplification. One extravert (a bold, fearless, high-energy type) may differ considerably from another (a sweet, warm, sensitive type), depending on the extraversion-related primary scale score patterns.
I had been suggesting to use the 16PF5 (or 15FQ+) normative test since years and discard the Big 5 test forever.

2) How they calculate different similarity indices at page 5.
"One important issue in providing a clear interpretation of the similarity literature is that there are a variety of ways to measure similarity, and the choice of method involves both theoretical concerns and statistical complexities (see Chapter 12 of Kenny, Kashy, & Cook, 2006, for a complete discussion)." at page 3.
"Perhaps the most important novel contribution of this work is the systematic examination of the ways that various similarity indices are associated with relationship and life satisfaction. In past work, researchers have debated which index should be used when examining the association between similarity and relationship outcomes." at page 11

"Methodological and data analytic advances in the study of interpersonal relationships: Introduction to the Special Issue" says ".. It is also important for investigators to challenge statisticians to create new analytic techniques when existing ones are inadequate. These tasks are left to you, the reader."



Researchers in the Personality Based Recommender Systems arena are also testing different formulas to calculate similarity, useless at all because they use the Big5 to assess personality of users.
You can see:
"Using Personality Information in Collaborative Filtering for New Users" "Design and User Issues in Personality-based Recommender Systems" "Emotive and Personality Parameters in Multimedia Recommender Systems" "Personality based user similarity measure for a collaborative recommender system" "The LDOS-PerAff-1 Corpus of Face Video Clips with Affective and Personality Metadata" "Addressing the New User Problem with a Personality Based User Similarity Measure" "Improving the believability in the interaction of synthetic virtual agents: Towards Personality in Group Dynamics"

Book
"Recommender Systems based on Personality Traits: Could human psychological aspects influence the computer decision-making process?"

Moreover, this is the list of milestone papers not even cited in
"Predicting relationship and life satisfaction from personality in nationally representative samples from three countries: the relative importance of actor, partner, and similarity effects.":

* Charania & Ickes (2009) paper: "Personality influences on marital satisfaction: Integrating the empirical evidence using the Actor-Partner Interdependence Model (APIM) model"
"... substantial level of inter-partner personality similarity for seven of the thirteen personality traits studied, with four of the similarity correlations exceeding 0.38 ..."

* Rammstedt & Schupp (2008) paper: "Only the congruent survive - Personality similarities in couples. Personality and Individual Differences"
".... Results reveal that among the Big Five dimensions, there are strong differences in spouses' congruences. While for Extraversion and Emotional Stability, congruence is close to zero, correlations averaging at 0.30 are found for Agreeableness, Conscientiousness, and Openness."

* Barelds & Dijkstra (2008) paper: "Do People Know What They Want: A Similar or Complementary Partner?"
"In The Netherlands, where this study was conducted, almost 40% of the divorcees report mismatches in personalities as the major cause of their break-up (De Graaf, 2006; Amato and Previti, 2003). .... although several studies have revealed similarities between partners in their personalities (e.g., Buss, 1984; McCrae, Martin, Hrebícková, Urbánek, Boomsma et al., 2008) only few studies have investigated the extent to which similarity in personality leads to romantic attraction (Barelds and Dijkstra, 2007). From their finding that couples across age groups show the same partner similarities (McCrae et al. 2008) conclude that mate selection, rather than convergence over time, accounts for personality similarity among partners." "Finally, the present study explored a recent issue uncovered by Eastwick and Finkel 2008; also Kurzban and Weeden, 2007; Todd, Penke, Fasolo, and Lenton, 2007 who found that people often report partner preferences that are not compatible with their choices in real life."

* McCrae, Martin, Hrebícková, Urbánek, Boomsma et al. (2008) paper: "Personality Trait Similarity Between Spouses in Four Cultures"
"... Most assortment effects were small, but correlations exceeding 0.40 were seen for a subset of traits, chiefly from the Openness and Agreeableness domains. ... This suggested that mate selection, rather than convergence over time, accounted for similarity"

* Barelds & Dijkstra (2007) paper: "Love at first sight or friends first? Ties among partner personality trait similarity, relationship onset, relationship quality, and love"
"... partner personality trait similarity was related to relationship quality as a function of both relationship onset and specific personality traits. "

* Bekkers, van Aken & Denissen (2006) paper: "Social Structure and Personality Assortment Among Married Couples"
"... Personality characteristics like agreeableness and neuroticism are good predictors of marital conflicts and ultimately of union dissolution, even across different relationships (Robins, Caspi & Moffitt, 2002). .... In sum: spouses with higher levels of neuroticism and openness, spouses with lower levels of agreeableness, and couples with more dissimilar personalities at the time of marriage are more likely to divorce."

Although none of the above papers use the 16PF normative personality test (they mostly use different versions of the normative Big5 personality test instead) and linear or logistic multivariate regression equations to calculate similarity, they clearly show a connection between personality similarity and marital happiness / dyadic success (stability and satisfaction) for some persons.


That is why I had invented a quantitative method to solve the problem of similarity!


The 16PF5 normative personality test codifies personality with 16 variables taking integer values from 1 to 10 in stens (standardized tens).

(A) Warmth; (B) Reasoning; (C) Emotional Stability; (E) Dominance, (F) Liveliness; (G) RuleConsciousness; (H) Social Boldness; (I) Sensitivity; (L) Vigilance; (M) Abstractedness; (N) Privateness (O) Apprehension; (Q1) Openness to Change; (Q2) SelfReliance; (Q3) Perfectionism; (Q4) Tension.


The ensemble (whole set of different valid possibilities) of the 16PF5 is: 10E16, big number as All World Population is nearly 6.7 * 10E9



The 16PF5 result is a quantized pattern, like
John's 16PF5 Profile A:6.B:7.C:6.E:8.F:9.G:6.H:7.I:7.L:8.M:7.N:2.O:5.Q1:8.Q2:7.Q3:3.Q4:4
Lucy's 16PF5 Profile A:5.B:7.C:4.E:8.F:7.G:4.H:5.I:6.L:4.M:6.N:8.O:9.Q1:6.Q2:8.Q3:4.Q4:4

I had invented a high precision quantitative method to compare similarity between those quantized patterns, e.g.:

John's pattern is 74.79865772% +/- 0.00000001% similar to Lucy's.


Latest Research in Theories of Romantic Relationships Development outlines: compatibility is all about a high level on personality similarity* between prospective mates for long term mating with commitment.
*Similarity is a word that has different meanings for different persons or companies, it exactly depends on how mathematically is defined.



Also several studies show that pill users make different mate choices, on average, compared to non-users.

1) "Human oestrus" Gangestad & Thornhill (2008)
"Only short-term but not long-term partner preferences tend to vary with the menstrual cycle"

2) "Does the contraceptive pill alter mate choice in humans?" Alvergne & Lummaa (2009)
".. whereas normally cycling women express a preference for MHC (Major Histocompatibility Complex) dissimilarity in mates, pill users prefer odours of MHC-SIMILAR men, indicating that pill use might eliminate adaptive preferences for genetic dissimilarity."






Please see how the1stMap distorts because it shows you Greenland as big as South America
But see the2ndMap, constructed using the Hobo Dyer Equal Area Projection, it correctly shows
South America: Area 17,840,000 km2 (6,890,000 sq mi)
and
Greenland: Area 2,166,086 km2 (13th) 836,109 sq mi


Fig. 1 extracted from Personal Relationships, 6 (1999), 519-534.
"Taxometric and related methods in relationships research"
Fig. 1 shows how a variable can be masked by other variable.


Please see "An exercise of similarity"