operationalizing variables

Variables are really important in a psychological research as they do specify our results. How we manipulate our variables (such as behaviour, characteristics) will have a result on the outcome of the research. In order to gather the desired outcome we need to operationalise those variables. This means that we need to define in depth our independent variables and dependent variables. In other words we have to say how we want to measure the behaviour. For example Bandura (1961) intended to measure aggression. We cannot simply just measure aggression as there is different types of it. Therefore he specified the inter rater observer validity: such as kicking, punching the doll where the behaviour perceived as aggressive. There were three conditions in which children could either see a model who was behaving aggressively do the doll or not. The children were them observed if they would repeat aggressive behaviour or not to the doll.

 

Some of the behaviours cannot be seen and therefore we have to operationalise them in order to investigate the reason underneath. For example thoughts in depression cannot be overtly observed. Therefore we need to give for example a valid questionnaire which measure thoughts (independent variable) to see what thoughts people with depression have it (dependent variable). If the research operationalise variable in a right way it allows him/her to exclude any extraneous variables/confounding variables. This means that all the unwanted variables that could affect the results are controlled and do not affect the explanation of the behaviour. For example if our independent variable is a memory task, other variables such as: participant’s tiredness, mood etc could have an impact on the results (dependent variable). Therefore it is extremely important to strictly operationalise our independent variable. Good control over the variables is also beneficial to the research as it shows that the research is high in internal validity.

 

On the other hand operationalisation of the variables could be a bit subjective in some methods. Take into account natural experiment or observational studies. Yes you define the inter rater reliability (you operationalise what you will measure by specifying the patterns of behaviour that you look for) however every researcher have got they own scale and reasoning on what they perceive as right. This could lead to the researcher bias. For example, Rosehan (1973) conducted a research about people behaviours after labelling mentally ill people with different disorders. He and his colleagues were admitted to the psychiatric hospital on the basics of schizophrenia disorder. In fact they were perfectly fine they were just faking the symptoms of that disorder. The aim of this study was to observe how the medical staff treats people based on the label imposed. Obviously the behaviour that they reported was only observed by them and therefore the independent variables was not really operationalized. Clearly this threats internal validity of any research.

 

In conclusion the purpose of every research is to operationalise it variables in order to minimanise any errors that could possibly affect the findings and give wrong results. Researchers strive to make their research looks high in internal validly(good control) by sacrificing external validity (generalisability) .  Every research design have main two important variables that are being defined (operationalsied) . Independent variable is being manipulated to see the effect on the dependent variable. Different factors investigated will have different operationalisation.

Comments week 8 :)

1.

http://cerijayne.wordpress.com/2012/02/18/should-children-be-used-in-psychological-research/

2.

http://elrucron.wordpress.com/2012/03/04/manipulation-increasing-false-findings/#comments

3.

http://raw2392.wordpress.com/2012/03/02/should-animals-be-used-in-research-110312/

4.

http://lrowlands1.wordpress.com/2012/02/19/accidental-discoveries/

🙂

Discuss the use of laboratory experiment in accordance to assumption of cognitive approach.

Discuss the use of laboratory experiment in accordance to assumption of cognitive approach.

Mind Uploading – this short metaphor would probably the best describe the method used and assumptions of the cognitive approach.  Cognitive approach assumes that our behaviour is mainly based on how our cognitions operate. Cognitive psychology uses variety of different methods to investigate its assumptions, such as case studies (the famous case of KF). Although the preferred method in this discipline is laboratory experiment as it provides most scientific evidence supporting the assumptions. In other terms is a computer science discipline, that’s why metaphor used at the beginning is completely adequate. Let me explain why.

On the contrary to other psychological approaches such as behaviourism (that is based on observable behaviour), cognitive psychology focus on internal mental states.

‘’all processes by which the sensory input is transformed, reduced, elaborated, stored, recovered, and used. It is concerned with these processes even when they operate in the absence of relevant stimulation, as in images and hallucinations… Given such a sweeping definition, it is apparent that cognition is involved in everything a human being might possibly do; that every psychological phenomenon is a cognitive phenomenon.” By Neisser (1967)

One of the cognitive approach applications that laboratory design has been used for, its on memory research .

“Memory is the process of maintaining information over time.” (Matlin, 2005)

As memory is an internal state it cannot be measured by any other method than laboratory experiment. This is simply because we cannot observe memory but we can test for example :the recall of it in accordance to the theory of how we process information.

But what it is laboratory experiment? It is a procedure carried out in laboratory setting where all the variables are controlled. Therefore it is highly scientific as it can be replicated and extraneous variables are less likely to provide other explanation of the behaviour investigated as they are controlled as well.

Atkinson and Shiffrin, (1968) are well known in psychology for proposing the simplified model of memory (multi store model). They assumed that our memory poses couple of stores. How we process the information depends how the information flow through those systems. Firstly information enter sensory memory (information are stored for couple of seconds) them the information are passed to the short term memory (stored for 18 sec and we encode 7 information) them the information are transferred to the long term memory through attention and rehearsal. Long term memory has unlimited capacity for both storage and remembering information.

Murdoch (1962) investigated that theory using laboratory experiment. He presented participants with list of the words and asked them later to recall how many they could remember. He found that the words presented at the begging were better recalled (primacy effect) because they were transferred to long term memory. He also found that words at the end were better recalled (recency effect) because they were in short term memory.

There are lots of advantages to this method (already mentioned before). Such as scientific validity, good internal validity etc.

On the other hand this method has been criticised a lot for being low ecologically valid. This is because the artificial setting is created in order to investigate its theories. This could be off putting but we have to bear in mind that this method its not the only method that cognitive psychology uses. For example field experiment (eyewitness theories by Loftus and Palmer 1974) . Therefore it can be argued that cognitive psychology as a discipline is high in ecological validity.

Conclusively despite the disadvantages of the laboratory experiments as a method, cognitive psychologists still uses this method as main when investigating assumptions of the cognitive psychology. It is the best method to investigate the internal states because they can be objectively measured by using laboratory experiments.