correlations

• Correlation techniques

  Non-experimental methods used to measure how strong the relationship is between two or more variables.
• Co-variables

  The variables investigated in a correlation.
• types of correlation

  positive

  negative

  zero
• Positive correlation

  As on co-varibale increases the other co-variable increases.
• Negative correlation

  As one co-variable increases the other co-variable decreases.
• Zero

  Occurs when a correlational study finds no relationship between the variables.
• Correlational hypothesis

  Non-directional

  Directional

  Null
• Non-Directional

  There is a relationship between co-variable one and co-variable two.
• Directional

  There will be a positive/negative correlation between co-variable one and co-variable two.
• Null

  There is no relationship between co-variable one and co-variable two.
• strengths

  • useful initial tool for research - starting point to access possible relationships between variables before researchers commit to an experimental study.
  • Quick and economical to carry out.
  • Data is secondary - less time consuming.
• Limitations

  • cannot establish cause and effect - therefore we d not know which co-variable is causing the other to change.
  • 3rd variable that effects both co-variables making them appear linked when they are not.
• correlational coefficients

  • Used to measure the strength and nature of the relationship between two co-variables.
  • Ranges between -1.0 and +1.0
  • The near the number is to +1 or -1 the stronger the correlation
  • A perfect positive correlation has correlation coefficient of +1 and for a perfect negative correlation it is -1