Psychology AQA AS PSYA1

Experimental Method

• Experimenter manipulates an IV in order to see if there is a change in the DV.
• All other variables that may change results are controlled, held constant or eliminated.
• Participants are allocated to the experimental conditions randomly.

A hypothesis is made that the IV will affect the DV in some way. Confounding variables (unwanted variables) must be eliminated,

Advantages :               

• A cause-and-effect relationship can be formed
• It isn't time consuming as experiments can be forced (rather than waiting naturally)
• The experiment produces quantitative data
• The data can be generalized to the same population

Disadvantages:

• People usually are aware that they are taking part in the experiment so behaviour is altered
• It is not always possible to carry out experiments due to ethical rules.

Lab Experiments Occurs in the lab

Advantages

• Replicable of procedures - due to in-depth notes etc., the experiments can be carried out again if needs be.
• Sophisticated measuring and recording equipment can be used
• Great control over variables 

Disadvantages

• Loss of validity, high amounts of control make the situation artifical
• Demand characteristics

Ethical Issues

• Consent - informed consent must be given and the right to withdraw is available 
• Deception - some experiments involve deception. participants must be debriefed

Field Experiments are experiments carried out in the natural environment

Advantages

• Improved ecological validity - as experiment is carried out in a real life setting it can be generalized better.
• Reduction of demand characteristics - participants may be less conscious they are taking part.

Disadvantages

• Establishing controls - difficult to establish high levels of control over the IV's and DV's 
• Generalizing to other environments - results cannot be generalized to other real-life situations 
• Field experiments are usually more costly and take longer
• Use of technical equipment is difficult to use in field experiments.

Ethical Issues

• Consent - participants must give informed consent and the right to withdraw from the experiment
• Confidentiality - the identity of participants must be protected

Natural Experiments are experiments carried out in natural environment where IV is not controlled

Advantages

• Reduction of demand characteristics - participants less conscious that they are taking part
• Lack of direct intervention - experimenter doesn't intervene with the situation

Disadvantages

• Loss of control - making it hard to establish cause-and-effect relationships
• The desirable behaviour may be displayed once every few years

Ethical Issues

• Consent - fully informed consent must be obtained 
• Protection of participants
• Confidentiality - participants have the right to remain anonymous 

Correlational Analysis measures relationship between two variables

Advantages

• Measuring the strength of relationships - a quantitative value is given for the difference in variables
• Value to exploratory research - measurement of many variables and relationships can be seen

Disadvantages

• Causality - it is not possible to establish cause-and-effect only the relationship between variables
• Measurement of non-linear relationships - cannot be measured by common correlational techniques

Ethical Issue

• Consent - fully informed consent and right to withdraw
• Use of findings - researchers must consider how the research is going to be used, depending on whether it is sensitive, participants have a right to know how the findings will be used.

Observational techniques behaviour is watched and recorded and there is no manipulation of variables, it can differ in several ways depending on, the setting, the role of researcher and the amount of structure imposed

Advantages

• Value as a preliminary research tool - careful use of observation can lead to other hypotheses
• Validity - can provide useful means of high validity which can check other experiment findings

Disadvantages

• Control - low control over confounding variables
• Replication - difficult to obtain due to differences in settings
• Observer effects - the observer may change the behaviour being observed
• Costs can be high
• Coding systems may not be accurate and so interpretation of behaviour is different
• Hard to generalize the findings to any other situation

Oberservational Techniques (continued)

Ethical Issues

• Privacy - studies must respect the privacy and well-being of individuals studied
• Confidentiality and Consent - participants observed have a right to know about the study and when the findings will be used
• Use of findings -  researchers must consider how the research is going to be used, depending on whether it is sensitive, participants have a right to know how the findings will be used.

Questionnaires

Advantages

• Simplicity - questionnaires can be used with minimal amounts of training
• Speed and cost - large amounts of data can be collected quickly and cheaply
• Less influence of interpersonal variables - as researcher isn't there, there is a less chance for them to influence the information given

Questionnaires (Continued)

Disadvantages

• Problems with question wording, e.g. ambiguous questions, leading questions, interpretations of language and social desirability bias. respondents may not provide truthful answers
• Poorly designed questionnaires produce low quality of data
• Response rates - roughly 30% or less who are sent questionnaires actually complete them and return it, this means the sample is mostly not representative of the population
• Researcher effects and biases - if researcher administers the questionnaire personally the respondents may be influenced by the researchers age, appearance, gender etc.

Ethical Issues

• Privacy - questionnaires including sensitive questions must respect the privacy of respondents
• Consent - researchers need to protect the respondents right to withdraw
• Risk of harm - Investigators must protect respondents from psychological harm throughout
• Debriefing and support - Questions can cause distress to respondents and appropriate support must be made available 

 Interviews there are three main types of interview: structured, semi-structured and unstructured

Advantages

• Flexible - interview can explore complex issues that may be difficult to investigate in other methods
• Tackling sensitive topics - interviews can identify aspects of behaviour that are private, these topics would be more difficult to explore using a more impersonal research method

Disadvantages

• Interpreting data - Misinterpretation of partial interpretation of data can occur
• Time and effort - some people may not want to meet the interviewer at a pre-arranged place and time and so this limits who can be interviewed
• Effects of interpersonal variables - factors such as gender and age may affect interaction between the two and so the amount of data obtained can be lessened.
• Demand characteristics may occur. such as social desirability
• The need for training and also the cost to carry out the interviews 

Ethical issues are similar to those of questionnaires

Case Studies

Advantages

• Rich and interesting data is produced that have a high degree of realism
• Challenging existing theory - if single case studies contradict a theory then a theory may have to be modified in some way to accommodate for the new evidence

Disadvantages

• The low reliability of much case study research - findings are unlikely to be replicated
• The findings may be subjective - case studies are usually based on long interviews and observations during which relationships may establish.
• Selecting from large amounts of data - researcher may have to select which aspects of the data to include or leave our which makes the findings more subjective 
• Distortions - if the individual is required to recall historical events, the data can be distorted.

Ethical Issues

• Observation and interviews are most common way, so issues are the same as those.