filter theory

• Filter theory is an explanation of attraction that states a series of factors progressively limit the range of available romantic partners to a smaller pool of possibilities
• Kerchoff and Davis (1962):

  •Compared attitudes and personalities of student couples in short term (less than 18 months) and long term (more than 18 month) relationships

  •Came up with a filter theory to explain how relationships form:

  1)First we consider the field of availables (pool of potential partners)

  2)From this we select the field of desirables using 3 filters of varying importance
• 1st filter: social demography

  Demographics are features that describe populations

  Social demographics refer to a range of factors that influence your chances of meeting someone e.g. age, education, location, social class etc.

  You are more likely to meet and have meaningful encounters with those who are physically close and share similar social demographics as yourself.

  Anyone too ‘different’ (e.g. too far away, different religion) is not a potential partner and ‘filtered’ out before the next stage.
• 2nd filter: similarity in attitude

  We find partners who share our basic beliefs and  values attractive, particularly for couples who have been together less than 18 months.

  In the early stages of a relationship agreeing on basic values promotes better communication and self-disclosure.

  If similarity doesn’t exist, the relationship often fades after on a few dates and these partners are ‘filtered’ out.
• 3rd filter: complementarity

  Over time, similarity becomes less important and is replaced by a need for your partner to balance (compliment) your traits with opposite ones of their own e.g. One partner can’t cook and the other one can.

  The idea that opposites attract.

  This is the most important factor in relationships longer than 18 months.
• Strength

  Kerchof and Davis original study conducted a longitudinal study in which both partners in dating coupes completed questionaires to assess two main factors similarity of attitudes/valus and complementary needs. The study found that closeness was associated with similarity of values but only for couples who had been together less than 18 months. For couples in longer relationships, complementarity of needs predicted closeness.

  This study provided evidence that similarity is important in the early stages of a relationship, but complementarity is more important later on.
• Weakness

  many studies have failed to replicate the original findings of Kerckhoff and Davis. He put this down to social changes over time and also to problems in defining the depth of a relationship in terms of its length. Kerckhoff and Davis chose an 18-month cut-off point to distinguish between short-term and long-term relationships.

  They assumed that partners who had been together longer than this were more committed and had a deeper relationship.

  This is a questionable assumption which means that filter theory is undermined by the lack of validity of its evidence base.
• Weakness

  complementarity may not be central to all longer-term relationships.

  A prediction of filter theory is that in the most satisfying relationships partners are complementary.

  However, Patrick Markey and Charlotte Markey (2013) found that lesbian couples of equal dominance were the most satisfied. Their sample of couples had been romantically involved for a mean time of more than 4½ years.

  This suggests that similarity of needs rather than complementarity may be associated with long-term satisfaction, at least in some couples.
• Weakness

  actual similarity matters less in a relationship than whether partners percieve or believe themselves to be similarthis was supported by meta-analysis research. They found that actual similarity affected altraction only in very short-term lab-based interactions. In real-world relationships, perceived similarity was a stronger predictor of attraction.

  Therefore perceived similarity may be an effect of attraction and not a cause, which is not predicted by the filter model