Research Methodology

Research Methodology
 
Laboratory Experiment
This type of experiment is controlled under highly controlled conditions.Laboratory Experiments allow precise control of variables. the purpose of control is to enable the experimenter to isolate one key variable selected in order to observe its effects on other variables. Overall, control is intended in order to identify that independent variables are the only ones that influence dependent variables.

Laboratory Experiment is argued that it allows us to make statements about cause and effect, because unlike non-experimental methods they involve the deliberate manipulation of one variable, while trying to keep all other variables constant.
Additionally, experiments can usually be easily replicated. However, this method is not always typical of real life situations. These types of experiments are often conducted in strange and contrived environments in which people are asked to perform unusual or even bizarre tasks. The artificiality of the situation, together with the 'unnatural' things that the participants may be asked to do, jointly produces a distortion of behaviour. Therefore, it should be difficult to generalise findings from experiments because they are not usually ecologically valid (true to real life).
A further difficulty with the experimental method is demand characteristics. Demand characteristics are all the cues which convey to the participant the purpose of the experiment. If a participant knows they are in an experiment they may seek cues about how they think they are expected to behave. Another problem with the experimental method concerns ethics. For example, experiments nearly always involve deceiving participants to some extent and it is important to recognise that there are very many areas of human life which cannot be studied using the experimental method because it would be simply too unethical to do so.

Example
An example is the Reicher and Haslam carried out this experimental case study to examine the consequences of randomly dividing men into groups of prisoners and guards within a specially constructed institution over a period of 8 days.
Unlike the prisoners, the guards failed to identify with their role. This made the guards reluctant to impose their authority and they were eventually overcome by the prisoners. Participants then established an egalitarian social system. When this proved unsustainable, moves to impose a tyrannical regime met with weakening resistance.
Haslam and Reicher suggest that it is powerlessness and the failure of groups that makes tyranny psychologically acceptable.


Field Experiment.
A field experiment is an experiment that is conducted in ‘the field ’. That is, in a real world situation. In field experiments the participants are not usually aware that that they are participating in an experiment.
The independent variable is still manipulated unlike in natural experiments. Field experiments are usually high in ecological validity and may avoid demand characteristics as the participants are unaware of the experiment. However, in field experiments it is much harder to control confounding variables and they are usually time consuming and expensive to conduct.
In field experiments it is not usually possible to gain informed consent from the participants and it is difficult to debrief the participants.
The strengths: 
1. Mundane realism-i.e. can apply the results to everyday life (everyday environment).
2. Less prone to demand characteristics (i.e. the participant is more likely to behave normally instead of either pleasing the researcher or going against the researcher).
The main disadvantages:
1. Less control over extraneous variables (i.e. other things that could affect the results other than the IV).
2. Less replicable than Lab experiments (i.e. harder to repeat because every set of participants' everyday environment will be slightly different).

Example
Piliavin, Rodin and Piliavin carried out a field experiment to investigate helping behaviour towards different types of victims.
Piliavin et al. note in their study that social psychologists became particularly interested in the behaviour of bystanders following the case of the brutal murder of Kitty Genovese in New York in 1964. The murder attracted interest from psychologists because according to the press not one person out of the 40 people, who witnessed the attack lasting over half an hour, tried to help or contacted the police.
Many laboratory studies were carried out by social psychologists to test bystander apathy. That is. the phenomenon of when observers of an emergency situation do not intervene. Importantly social psychologists looked for the cause of bystander behaviour not in the type of people who do or do not help but in the situational factors which influence helping behaviour.

Natural (Quasi) Experiment
Natural Experiment is when the independent variables are not manipulated and occurred by in nature.
In a quasi experiment the researcher takes advantage of pre-existing conditions such as age, sex or an event that the researcher has no control over such as a participants’ occupation. A strength of quasi experiments is that participants are often unaware that they are taking part in an investigation and they may not be as artificial as laboratory experiments. However, it is argued that with quasi experiments it is harder to establish causal relationships because the independent variable is not being directly manipulated by the researcher.
It is worth noting that quasi experiments are very common in psychology because ethically and practically they are the only design that can be used.

Example
An example occurred in Helena, Montana during the period from June 2002 to December 2002 when a smoking ban was in effect in all public spaces in Helena including bars and restaurants. Helena is geographically isolated and served by only one hospital. It was observed that the rate of heart attacks dropped by 60% while the smoking ban was in effect.


The variable which is being manipulated by the research is called the independent variable.
The change in behavior measured by the research is the dependent variable.
All other variables which might affect the results and therefore give us a false set of results are confounding variables.
Research Hypothesis is the paring down of the problem into something testable and falsifiable.

Null Hypothesis is a hypothesis which the researcher tries to disprove, reject or nullify.
Treatment Group is the item or subject that is manipulated
Control Group is identical to all other item or subjects that you are examining with the exception that it does not receive the treatment or the experimental manipulation that the treatment group receives.


References:
http://www.holah.co.uk/page-detail.php?slug=experimental
http://www.holah.karoo.net/glossary.htm#L