3.2 Correlations

• What is a correlation?

  A relationship between two factors
• In a positive correlation as x increases what does y do?

  y increases
• In a negative correlation as x decreases what does y do?

  y decreases
• In a graph with no correlation as x increases what does y do?

  y stays the same
• How can a cause be proven?

  Using specific scientific evidence and data from experiments
• A graph shows a positive correlation between the rate of skin cancer and the number of ice creams eaten.

  Is eating ice creams a cause for skin cancer?

  There is a positive correlation between skin cancer and the number of ice creams eaten but a correlation does not prove causation, other factors like UV radiation may have caused the skin cancer. The anomalous result like eating one ice cream doesn't fit the relationship anyway.
• What are the risk factors of: Lung disease Skin cancer Heart disease

  Lung disease - smoking, weakened immune system, vaping.

  Skin cancer - UV exposure.

  Heart disease - smoking, high salt in diet, high blood pressure.
• How do you predict a result when provided with other results?

  Draw a line of best fit then extrapolate the line to predict future results.
• What is the calculation for uncertanty?

  Uncertanty = 1/2 x smallest unit on measuring instrument