SEARCH
You are in browse mode. You must login to use MEMORY

   Log in to start

level: Correlation

Questions and Answers List

level questions: Correlation

QuestionAnswer
A positive correlation- When variables increase together - Relationship
A negative correlation- As one variable increases the other decreases - Relationship
No correlation- The two variables are uncorrelated
Strengths of a correlation- Calculates strength of relationship between variables - If get strong correlation, good starting point for experiement - Can be really flexible
Weaknesses of correlation- Cannot identify cause and effect - just patterns - There may be a false correlation
How to measure the strength of a correlation - Use a Correlation test eg Spearman’s Rho- Gives number called a correlation coefficient - Number between -1 and +1 and states how strong a correlation is
Different coefficients related to correlations- Number close to +1 = positive correlation - Number close to -1 = negative correlation - Number close to 0 = no correlation
Scatter diagrams- Title, labelled axes, appropriate units - No line of best fit - Doesn't matter which variable is on the x or y axis - Shows correlation but no conclusion about hypothesis
Usefulness of scatter diagrams- Shows correlation between co-variables