Ecological validity is ultimately the ability to generalise the findings of a study beyond the situation in which the behaviour was tested and relate it back to real life. If a piece of research is conducted in a situation that is likely to happen in real life then it can be said that study has a high level of EV. However, if a piece of research is conducted in a setting that lacks mundane realism and has little (if any) relation to real life it will then be argued to lack in ecological validity.

A key strength for a study having high ecological validity is that it allows psychologists to generalise the findings; showing how behaviour is affected in real-life or with real life tasks. Therefore, the researcher can ensure that the practical applications generated from the study will be relevant and useful to life. Meaning that through practical applications psychologists are able to change situations and benefit individuals/ society for the better.

A drawback of a study with high ecological validity may be that it will be difficult to maintain controls. If people are studied in a natural, everyday setting then it may be difficult to prove that a true cause and effect has been found. For example Piliavins study conducted on the New York underground, although it tested helping behaviour in a real life situation the study was conducted on the same subway during the hours of 11-3 and therefore people may have already been in the study and guessed the aims, therefore shown demand characteristics and not act how they truly would.

There is however strengths to studies that lack in ecological validity. For example, studies with low ecological validity are often easier to replicate and therefore will have increased reliability. The ability to replicate a study also increases the scientific nature of research and ultimately psychology’s reputation as a science.

A major weakness of a study that has low ecological validity is that it is much harder to generalise the findings from the study as they are not representative of the real world or tasks. A key example of research with low EV could be the study conducted by Bandura. Although practical applications such as the watershed and film ratings were generated from this study it still lacks mundane realism. Children are not normally presented with a bobo doll and therefore aggression towards bobo dolls is not often seen. Aggression is more commonly on observed by children on tele, in a film or against another human being, not a bobo doll.  A further drawback is that the children taking part in the study who saw the aggressive model and their behaviour towards the bobo doll were then put straight into the situation themselves. When a child sees aggression, for example on a game or in a film, they aren’t then put straight into that situation themselves and therefore may not have acted that way a few weeks later when presented with a bobo doll.