Correlations

• What can analyzing two sets of data for a correlation reveal?

  Potential relationships and the strength of those relationships
• What does the term "correlation coefficient" refer to?

  A numerical measure of the strength and direction of a correlation
• How does a correlational study differ from an experimental study?

  In a correlational study, no variables are manipulated; only measurements are taken
• What are co-variables in a correlation?

  Variables that a researcher measures and compares
• Which two co-variables might a researcher compare in a study?

  Age and IQ
• What is a scattergram used for?

  To display data collected in a correlation study
• How would you plot a correlation on a scattergraph?

  By plotting data pairs on X and Y axes
• What does a positive correlation indicate?

  When one co-variable increases, the other also increases
• What does a negative correlation indicate?

  When one co-variable increases, the other decreases
• What is zero correlation?

  When there is no relationship between the co-variables
• How can the strength of a correlation be described?

  As weak, moderate, strong, or perfect
• What is the range of a correlation coefficient?

  From -1 to 1
• What does a correlation coefficient of 0.8 indicate?

  A strong correlation
• What is a critical evaluation of correlation studies?

  Correlation does not imply causation
• What does the phrase "correlation does not show causation" mean?

  It means we cannot determine which variable influences the other
• What could be a third variable affecting the correlation between ice cream sales and drowning?

  Temperature
• What is a positive evaluation of using correlations in research?

  They can highlight potential causal relationships for further investigation
• What is one ethical advantage of correlational research?

  It often involves measuring pre-existing variables
• Why is the correlation coefficient a useful tool?

  It describes the strength of a correlation
• What are the strengths and limitations of correlational studies?

  Strengths:

  • Highlight potential causal relationships
  • Few ethical problems with pre-existing variables
  • Useful correlation coefficient for strength description

  
  

  Limitations:

  • Correlation does not imply causation
  • Potential extraneous variables not controlled