Introduction to Correlations Methods & Techniques Produced by
Laboratory Field Experimental Quantitative Natural Research Method
Observations Correlation Surveys Surveysand andInterviews Interviews Case Studies
Key Terms Positive correlation â€˘ A positive correlation is when one variable increases the other variable increases as well. For example, as the level of secure attachment increases the number of smiles given increases.
Key Terms Negative correlation â€˘ A negative correlation is when one variable increases the other variable decreases. For example, Dilalla (1988) found a negative correlation between the amount of time children spend in care and the amount of pro-social behaviour they display.
Introduction to Correlations • Correlation Analysis - A descriptive technique that psychologists use to measure the relationship between variables. • For example we could say we wanted to measure the correlational between age and memory. • By this we mean that we want to measure and see how ones memory performs as one gets older. • If your memory performs better as you get older than we can say that this is a positive correlation because as age increases memory increases.
• If your memory performs worse as you get older than we can say that this is a negative correlation because as age increases memory gets worse. • Many correlational techniques calculate a correlation coefficient,- (this is the data produced using a correlation technique) that has a value on a scale between +1 (This is a perfect positive correlation) and -1 (This is a perfect negative correlation). • As such the correlational method is not a research method. The term is used to refer to those types of non-experimental methods that specifically try to measure relationships or correlations between two variables.
Advantages of the Correlation Method • Measuring the strength of relationships – correlational techniques provide a precise way of measuring between specific variables.
• Value of laboratory research – correlational techniques allow for the measurement of many variables at one given time and gives us the opportunity to investigate the relationships between them at the same time as well.
Disadvantages of the Correlation Method â€˘ The issue of causality â€“ It is impossible to establish cause and effect through research investigations that use correlational analysis.
correlational analysis only establish relationships between variables
Ethical Issues • Consent – the same issues of fully informed consent and right to withdraw apply here. • Use of findings – this usually applies to socially sensitive research. For example drug abuse – the question here is how is the results going to be used. For what benefit. The intentions of the researcher needs to be made known to the participants and their informed consent is needed not only for their participation but for the publication of the findings.
Key Points • Correlation establishes relationships or associations between co-variables. • There are different types of correlation. These are positive correlations and negative correlations. • A positive correlation occurs when an increase in one variable leads to an increase in the other variable . • A negative correlation occurs when an increase in one variable leads to a decrease in the other variable.
â€˘ A scattergram provides a graphical representation of a correlation. â€˘ The correlation coefficient is the number that tells us the strength and direction of the relationship between two variables. It always lies between +1 and -1.
Examiners Note • When writing a correlational hypothesis always operationalise the variables and if a directional hypothesis is asked for then use the terms positive and negative. • For example: ‘There will be a significant positive correlation between the number of hours of violent television viewed and scores on an aggression questionnaire’.
Examiners Note • Never make the mistake of thinking that the correlation indicates or means ‘cause and effect’. • It indicates and means that there is only a relationship or an association between two variables. • Be careful when writing about correlational data as it is easy to slip into talking about one variable causing a change in the other variable.
• You should be able to explain at least two advantages and disadvantages of the different methods. • Remember if two marks are available then the mere identification of the advantage/disadvantage would only gain you one mark; you need to elaborate to gain the full marks. • For example, stating you cannot establish cause and effect would gain you on mark.; to gain two marks you would need to elaborate.
• ‘A correlation does not establish cause and effect, it only establishes an association or relationship between two or more co-variables. There may well be a third variable that is causing this relationship’.