Significance levels

• Explain what is meant by the term ‘significance level’

  A numerical value that is usually expressed in value including two decimal places. This level tells you the margin of error that could occur in your results and shows the probability of rejecting the null hypothesis
• Explain what is meant by ’p<0.01’

  The probability that the results will be down to chance is 1% or less
• Explain why a psychological researcher might use a p value of p<0.01 rather than p<0.05

  A ‘stricter’ or more stringent level of measurement, such as p<0.05 has more probability that the findings are due to chance, which may not be acceptable in some research, e.g. clinical trials
• Explain the difference between the meaning of the symbol < (underlined) and < (not underlined)

  < (underlined) means less than or equal to, whereas < only means less than