Ao3

• Provides explanations for why people stay in abusive relationships. According to the model, if a partner feels that the investment they have made into the relationship will be lost they will be less likely to leave the relationship even when the costs are high (emotional or physical abuse) and there are few rewards. ​
• there is research to support this from Rusbult and Maltz where they found that women were more likely to return to an abusive partner if they felt they had invested in the relationship and didn’t have an more appealing alternatives.​
• • The majority of the research presented to support the model is correlational. Whilst it shows there is a relationship between the factors e.g. that investment influences commitment it does not show a direct cause and effect relationship between the two. ​ 
  • This is a problem because is limits the models validity as it would not be able to predict properly the types of investment or how much is needed for a long-term commitment in a relationship.​ 
• the lack of validity also means that we cannot use it to predict someone’s behaviour as to whether or not they will stay committed to the relationship which is a key goal in psychology. 
• Cultural bias is not an issue in the key meta-analysis study done by Le and Agnew. As the study took 52 studies it can be found to support the investment models cross multiple different cultures especially both individualist and collectivist culture. This is important because it means there is strong support for the investment model with the research conducted as it can be widely generalised across global populations. ​
• Investment model that is an explanation of relationship maintenance has validity for different sub-groups e.g. friendships, cohabiting couples, homosexual couples. This is also important as it shows the versatility of the model how applicable it is.