Scatter graphs and correlation

Question 1

what are correlations

Answer 1

a mathematical technique in which a researcher investigates an association between two variables, called co-variables

Question 2

what do correlations do

Answer 2

illustrates the strength and direction of an association between two or more co-variables (things that are being measured)

Question 3

what are the three types of correlation

Answer 3

• positive
• negative
• no correlation

Question 4

what are the weaknesses of correlations

Answer 4

• can only reveal how variables are related but not why
• do not demonstrate a cause and effect so we don’t know which co-variable caused the other to change
• may be an untested variable causing the relationship between co-variables
• co-variables can be misused and misinterpreted due to this

Question 5

what are the strengths of correlations

Answer 5

• a good preliminary measure before conducting research
• if interesting or strong patterns are found it could be a starting point for future research
• quick and cheap
• controlled environment and manipulation of variables is needed

Question 6

what is a correlation coefficient

Answer 6

using statistical tests to measure the relationship between variables that produce a numerical value between -1 and +1

Question 7

what does a correlation coefficient tell us

Answer 7

tells us the strength and direction of the relationship between the two variables

Question 8

what does +1 represent

Answer 8

a perfect positive correlation

Question 9

what does -1 represent

Answer 9

a perfect negative correlation