Social Exchange Theory: Relationships as Trade-Offs
Nobody wants to think of their relationship as a balance sheet. But most people can tell you, quite quickly, whether they feel they are putting in more than they are getting back — and that feeling turns out to predict a great deal.
📚 What you need to know
Social exchange theory (SET) is an economic theory of relationships. It borrows the language of banking, investment and finance.
It was proposed by Thibault and Kelley (1959) to explain how people judge the costs and benefits of a relationship.
For a relationship to thrive, each partner has to feel rewarded — to feel a sense of profit.
SET runs on the minimax principle: minimise losses, maximise profits. Profit = rewards − costs.
Rewards, costs and losses are entirely subjective and differ from couple to couple.
Couples negotiate the terms of the exchange, directly through talking or indirectly through experience.
The study you need is Utne et al. (1984), on equity and satisfaction in married couples.
The exchange
The core claim is simple. People stay in relationships that feel worth it and leave ones that do not, and ‘worth it’ means the rewards outweigh the costs by enough to feel like a profit.
What counts as a reward is personal. Being praised for cooking may mean everything to one partner and nothing at all to the other.
Negotiating the terms
Couples work out the exchange between them, sometimes by talking it through and sometimes just by learning what goes down well. One partner discovers that complimenting the other’s cooking lands every time, so they keep doing it. Nobody agreed that out loud; it was learned.
Sacrifices
Relationships also require sacrifices that offset the rewards: giving up nights out, living in a town instead of the countryside, putting up with each other’s families. In the long run these can build something more rewarding. But if costs pile up into arguments, conflict and resentment they destabilise the relationship instead, so a fine balance is needed — and that takes time, hard work and compromise from both sides.
The word to keep repeating is subjective. SET does not say what a reward is; it says each person decides. That single point is both the theory’s flexibility and its biggest measurement problem.
Key study: Utne et al. (1984)
Part of the study
What happened
Aim
To investigate how satisfied married couples felt, in relation to how equitable each partner believed the relationship to be.
Participants
118 married couples from the USA, aged between 16 and 45 (mean 26 for men and 24 for women). Most had dated seriously for over two years before marrying, and 74% had been married for four months or less.
Procedure
Each husband and wife was interviewed separately. Questions covered the history of the relationship, perceived equity or inequity within it, satisfaction with the marriage, and how stable the marriage seemed to them.
Results
Couples in equitable relationships reported the highest levels of contentment and satisfaction. Partners who felt their benefits outweighed their costs — inequity in their own favour — felt uneasy and guilty about the imbalance.
Conclusion
The most successful relationships appear to be those where both partners feel costs and benefits are divided fairly.
The finding worth quoting. Getting more than you put in did not make people happier — it made them feel guilty. That is a problem for a simple minimax reading of SET, which predicts people should want maximum profit. What actually satisfied couples was fairness.
Evaluating the theory
What is strong about it
Couples therapy that increases rewards and reduces costs has been found to improve joint satisfaction and happiness, which gives the theory practical support.
There is obvious real-world application. Common sense says relationships get judged on whether the costs outweigh the rewards, and SET puts a framework around that.
Interviewing husbands and wives separately was a good design decision — it stopped partners influencing each other’s answers.
What is weaker about it
Rewards, costs and profit are subjective variables that differ from person to person, which makes them very hard to operationalise. That limits the reliability of the theory.
People are complex and often unpredictable. Applying an artificial construct borrowed from economics to human relationships is difficult, so there is a lack of ecological validity in both the theory and the research built on it.
The theory struggles to explain why people stay in relationships that are clearly running at a loss.
Link to concepts
Change: SET research captures a single moment rather than tracking satisfaction over time. To be valid it really needs to be longitudinal, because relationships are not fixed and fluctuate for financial, personal and practical reasons. Utne’s couples were newlyweds — 74% married four months or less — so they had not had time to build up resentments about equity. A follow-up study would have been a genuinely useful addition.
Bias: asking couples about their own relationship invites several biases. Social desirability bias pushes people to present things in the best light. Recall bias distorts memories of past episodes. And some participants may report positive feelings about a partner while privately thinking negative thoughts, which is cognitive dissonance.
EXAM PRACTICE
Evaluate social exchange theory as an explanation of personal relationships. [22]
Step 1: outline the theory
Thibault & Kelley (1959). An economic model: profit equals rewards minus costs, and people follow the minimax principle.
Step 2: add the detail that shows understanding
Rewards and costs are subjective, and the terms of exchange get negotiated over time.
Step 3: the study
Utne et al. (1984). 118 married couples in the USA, husbands and wives interviewed separately about equity and satisfaction.
Step 4: the result that complicates the theory
Equitable couples were most content, and those who felt they were getting more than they gave felt guilty — not happier.
Step 5: evaluate
Useful in couples therapy, but subjective variables are hard to operationalise, the sample were newlyweds so the design should have been longitudinal, and self-report invites social desirability bias.
Theory + detail + study + complication + evaluationUsing the guilt finding to question minimax is real analysis. Do not just report it.
💡 Exam tip
Write the sum out: profit = rewards − costs. It is quick and it shows you know the model.
Use minimax principle by name.
The 74% married four months or less is your strongest criticism of Utne. Newlyweds have not had time for resentment to build.
Separate interviews for each partner is a design strength most students overlook.
SET and the matching hypothesis are both cost-benefit models. Comparing them makes a strong closing paragraph.
⚠ Common mix-up
Saying people want maximum profit. Utne found the happiest couples were the fairest, not the ones getting most.
Treating rewards as objective. They are entirely subjective and differ per relationship.
Confusing equity with equality. Equity means the exchange feels fair, not that both put in identical amounts.
Calling Utne an experiment. It used interviews, so it is self-report data.
Forgetting sacrifices. Costs willingly accepted can build a stronger relationship in the long run.
That completes Topic 3. Up next: Acculturation and Its Effect on Mental Health — go back to the start of 3.1 and see how much of the group behaviour material now reads differently.
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