Probability and significance

• Two types of hypotheses

  Null hypothesis - States that there is no significant effect or relationship between variables

  
  

  Alternative hypothesis - States there there is a significant effect of on the dependent variable as a result of the manipulation of independent variable
• What is significance?

  Statistical term. Lets us know how sure we are about a correlation.

  
  

  If its significant we reject the null hypothesis and accept the alternative hypothesis
• What is probability?

  Calculation of how likely it is for an event to happen.

  • 0 = statistical impossibility
  • 1 - statistical certainty

  The usual level of significant = 0.05 or 5 percent

  P = 0.01 - used by psychologists especially if they're study is attempting to support a controversial theory or replicate another study
• What are the 2 types of errors?

  • Type 1
  • Type 11
• Types of errors

  Type 1 Error -

  • Researcher accepts the alternate hypothesis when it's false and rejects the null hypothesis
  • False positive

  Type 11 Error -

  • Researcher accepts the null hypothesis when its false, should've rejected it
  • False negative