laboratory + field experiment

• laboratory experiment: a laboratory experiment conducted in a special environment where variables can be carefully controlled, participants are aware that they are taking part in an experiment though they may not know the true aim of the study
• laboratory experiment: it is this awareness of being in a study that contributes to the contrived nature of such studies - participants may alter their behaviour because they know it is being recorded
• laboratory experiment: laboratory experiments also often involve quite artificial materials such as consonant syllables (Peterson and Personson's study of STM) and this again makes the experience less like everyday life
• laboratory experiment: in addition of course the laboratory environment may seem artificial and uncomfortable - but remember it is by no means the environment alone which contributes to the contrived nature of lab experiments
• field experiments: a field experiment is conducted in a more natural (or 'ordinary') environment, i.e. in the field (as distinct from 'a field' - the 'field' is anywhere outside a laboratory)
• field experiments: as w/ the laboratory experiment the IV is still deliberately manipulated by the researcher and the researcher measures the DV
• field experiments: a key feature of a field experiment is that participants are usually not aware that they are participating in an experiment for this reason their behaviour may be more natural
• field or lab experiment: sometimes it isn't very easy to work out whether a study is a laboratory or field experiment
• field or lab experiment: we described the weapon focus study (Johnson and Scott, 1967) this study might seem on the surface to be a lab experiment but it was conducted under controlled conditions in room unfamiliar to the participants
• field or lab experiment: but the actual behaviour that was being measures (the participants' ability to identify the man running through the room) reflected natural behaviour
• field or lab experiment: the participants were not aware that it was this behaviour that was being studied and therefore were behaving naturally so this makes the study more like a field experiment
• any study which is conducted in a natural environment is called a field study, it is only a field experiment if there is an IV that has been manipulated by an experimenter
• evaluation lab S: it is possible to control the environment closely making replication easier and increasing reliability
• evaluation lab S: as participants are in an artificially controlled setting they are more likely to know they are being studied and therefore be able to consent
• evaluation lab L: the environment is artificial meaning that the behaviour seen may lack realism too
• evaluation lab L: as participants know they are being observed demand characteristics are more likely to influence their behaviour so internal validity may be low
• evaluation field S: as participants are in their natural environment the behaviour seen is more likely to be realistic thus increasing ecological validity
• evaluation field S: participants may not know they are being studied so they would be less prone to demand characteristics improving experimental validity
• evaluation field L: the environment is less controlled so there is more chance of extraneous variables influencing the results
• evaluation field L: participants may not be aware they are being studied meaning that gaining consent may be difficult
• laboratory experiment: take place in a controlled setting such as a laboratory, the participants can be randomly allocated to conditions
• field experiment: take place in participants' natural environments, participants can be randomly allocated to conditions