Data Analysis Flashcards
What is a positive correlation?
As one variable increases so does the other
What is negative correlation?
As one variables increases, the other variable decreases
What is zero correlation?
Occurs when a correlational study finds no relationship between variables
What is the correlation coefficient used to measure?
The strength and nature (positive or negative) of the relationship between 2 co-variables
Can range between -1 and +1
Perfect positive correlation has a correlation coefficient of +1
Perfect negative correlation is -1
What do correlational studies measure?
The strength of a relationship between 2 or more variables
When can correlational studies be used?
When a laboratory experiment would be unethical
Secondary data can be used in correlational studies which alleviates the concern over informed consent as the information is already in the public domain
Is it possible to establish a cause and effect relationship through correlating co-variables?
No
What is the third variable problem?
As a cause and effect relationship cannot be established, a researcher cannot conclude that one variable causes the other variable to increase/decrease as there could be other factors which influenced the relationship
Do correlations identify curvilinear relationships as well as linear?
No- correlations only identify linear relationships- not curvilinear.
What does curvilinear mean?
The relationship is positive to a point then it declines once one variables reaches high limits
What is primary data sometimes called?
Field research
What is secondary data sometimes called?
Desk research
What is a meta-analysis?
A process in which data from lots of studies that use the same techniques and research questions are combined
A statistical analysis is then performed on the results of these studies to produce an effect size as the dependent variable in order to assess overall trends
What type of data does meta-analysis use?
Secondary data
What are the stats for normal distribution?
68% of the data is collected around the middle, 27% is on the outside and roughly 4% is around the edges