How do you make the decision of who you want to be with romantically? Do you rely on how another person looks or do you take into account other categories that they have to offer? If you answered this and said you choose them based on different categories, then what are those categories? Let's discuss one of the explanations for this below: the filter theory.
- First, we will look at what Kerckhoff and Davis' (1962) filter theory is.
- Next, we will discuss the filter theory in psychology and look at its characteristics.
- We will then explore an example of the filter theory, with respect to relationships.
- Finally, we will evaluate the filter theory and identify its strengths and weaknesses.
Fig. 1 - The filter explores how we make choices with our partners.
Kerckhoff and Davis (1962) Filter Theory
Kerckhoff and Davis (1962) attempted to answer questions about how we choose our potential mates and did so by studying student couples in relationships.
They found that individuals choose their partner based on some important criteria and went ahead to call these criteria 'filters', which led to the birth of the filter theory.
The Filter Theory in Psychology
With so many single people in the world, it can be difficult in trying to choose a partner. Using these filters helps individuals narrow down this pool of availability to those who they believe they have the best chance of a relationship with.
The filter theory states that there are three filters that individuals apply when choosing their partner.
Fig. 2 - How do we choose a potential life partner?
The Filter Theory in Relationships: Characteristics
The filter theory consists of three filters, according to Kerchoff and Davis (1962). Individuals take into account each of these, step-by-step, and then make their decision on who they want to be with in intimate relationships.
The three filters are:
- Sociodemographic characteristics
- Similarity in attitudes
- Complementarity
Sociodemographic Characteristics
When we talk about sociodemographic characteristics, comprising of social and demographic characteristics, we mean things like physical proximity, age, and education level amongst other factors.
Not only can these characteristics determine whether or not you will get the opportunity to meet someone, but also determine whether or not you will be able to form a relationship with them.
Ultimately, you cannot form a relationship if you don't meet and get the opportunity to spend time with each other in the first place.
The likelihood of an individual forming a relationship with someone close to them in age, and with someone who lives nearby is far greater than if their potential partner was several years older/younger and lived miles or hours away.
Similarity in Attitudes
Similarity in attitudes refers to wether individuals share the same, or even similar, beliefs when it comes to situations like family and careers. It focuses on attitudes, values, and beliefs.
In their study, Kerckhoff and Davis (1962) asked participants to fill out surveys at the start of their relationships and after seven months. The results of these questionnaires showed that the similarity in values aspect was important for those in long-term relationships less than 18 months.
You are more likely to form a relationship with someone who wants children in the future, like you do, as opposed to someone who doesn't.
Complementarity
While the similarity in attitudes is an important factor, complementarity goes one step further.
Complementarity states that each partner 'complements' the other and fulfils each other's needs.
When Kerckhoff and Davis examined couples in a relationship longer than 18 months, they found this to be the most important factor.
You might have an excellent ability to socialise, whereas your partner might be great at organisation - you can then help each other by initiating social situations for you and your partner to engage in, and your partner can help you stay organised in terms of work and school, for example.
Fig. 3 - The three levels of the filter theory contribute to the development of a happy relationship
Complementarity in a relationship is important because it stresses the need for partners to not be 100% alike; it allows both individuals to assume different roles, which contributes to the overall happiness of the relationship.
Imagine if both you and your partner loved cooking but hated cleaning - what would happen? A mess would pile up until one person "gives in" and cleans. This situation could cause resentment to grow, and complementarity aims to avoid exactly that.
If each of you assumes a unique role that also complements the other's role, then you will be able to work and live in harmony, contributing to the overall satisfaction with your relationship.
Filter Theory Psychology Example
Even though we've discussed examples of each stage of the filter theory separately, it might be easier to understand if we are able to see it all in one go.
The Filter Theory: Relationships
Let's have a look at how it works in relationships below.
Let's say you go out with your friends to a party which has people of all ages. You are 24 years old and are in a position where you would like to meet someone of your age to form a stable relationship. Your friend introduces you to 4 people - one is 24 years old, one is 27 years old, one is 30 years old and one is 35 years old.
To narrow this pool of individuals down, you will start using the filter theory. The first level is sociodemographic characteristics; since those who are 24 years old and 27 years old are the closest to you in terms of age, your pool of individuals will narrow itself down from 4 individuals to these 2.
The next level is a similarity in attitudes. Let's say the individual that is 24 years old has no serious career goals at the moment and doesn't want kids in the future - completely opposite to you - and the 27-year-old has goals to travel the world, be financially stable and wants kids in the future. This will further narrow your pool down to just one individual, and you will find yourself more drawn to the 27-year-old.
As you spend more time together, you will begin to solidify your relationship, and this is when complementarity will come in. You might love cooking and your partner may hate it - you will then assume your specific roles (of you as the chef, and your partner as the cleaner) and your relationship will begin to flourish.
You will both be able to add to each other's lives in a beneficial way, contributing to the overall success and happiness in your relationship.
Evaluation of the Filter Theory
Let's evaluate the filter theory to identify its strengths and weaknesses.
Strengths
First, let's identify some key studies associated with supporting the filter theory.
- Winch, Ktsanes and Ktsanes (1955) found that similarity of interests, attitudes, and personality traits is essential at the beginning of a relationship, while complementarity is vital in the long run.
- Gruber-Baldini et al. (1995) conducted a longitudinal study of couples at age 21. They found that those with similar educational backgrounds and ages at the beginning of their relationship were more likely to succeed. This finding supports the sociodemographic filter, with educational level and age being sociodemographic factors.
- Winch (1958) surveyed 25 married couples, examining their characteristics and how husbands choose their wives. They found that complementary needs had a stronger correlation in mate selection.
Weaknesses
Now, let's examine the weaknesses of the filter theory.
- Some psychologists have struggled to replicate Kerckhoff and Davis' findings because of the controversy over what constitutes a 'long-term' and 'short-term' relationship. By assuming that 18 months is a 'long-term relationship', Kerckhoff and Davis did not consider that some couples may take longer to complement each other.
- Anderson et al. (2003)³ suggested that couples are not similar from the beginning of a relationship but become more similar over time, thereby questioning the direction of causality Kerckhoff and Davis had assumed. If couples become more similar over time rather than assuming similarities at the start of the relationship, this affects the similarity filter.
The Filter Theory - Key takeaways
- The filter theory was developed by Kerckhoff and Davis in 1962. The filter theory states that there are three filters that individuals apply when choosing their partner.
- The three filters of the filter theory are sociodemographic characteristics, similarity in attitudes and complementarity.
- Sociodemographic characteristics refer to social and demographic characteristics, such as age and proximity. Similarity in attitudes refers to the similarity in values and beliefs between partners. Complementarity refers to how individuals complement each other and fulfil each other's needs.
- Complementarity in relationships is particularly important in long-term relationships because it allows both individuals to assume different roles, which contribute to the overall happiness of the relationship.
- Further research found that similarity of interests and attitudes are essential at the beginning of a relationship, while complementarity is vital in the long run, however, a weakness of the theory is that couples may not be similar from the beginning of a relationship but become more similar over time.
References
- Winch, R. F., Ktsanes, T., & Ktsanes, V. (1955). Empirical elaboration of the theory of complementary needs in mate-selection. The Journal of Abnormal and Social Psychology, 51(3), 508–513. https://doi.org/10.1037/h0042235
- Gruber-Baldini, Ann & Schaie, Klaus & Willis, Sherry. (1995). Similarity in Married Couples: A Longitudinal Study of Mental Abilities and Rigidity-Flexibility. Journal of personality and social psychology. 69. 191-203. 10.1037//0022-3514.69.1.191.
- Anderson, C., Keltner, D., & John, O. P. (2003). Emotional convergence between people over time. Journal of Personality and Social Psychology, 84(5), 1054–1068. https://doi.org/10.1037/0022-3514.84.5.1054
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