Normal Distribution

Cards (15)

  • normal distributions have a symmetrical distribution
  • normal distributions are the idealised perfect distribution
  • two properties of a normal distribution
    mean defines the position, sd defines the spread
  • 68% of all observations lies in 1SD from the mean both ways
  • 16% of the data lies outside 1SD of the mean
  • 95% of the data lies within 3SD of the mean
  • z score
    measured in term of sd from the mean
  • z score is how many sd a value is away from the mean
  • What would be the z score for 0.83?
    0.7967
  • z scores can be used to calculate the proportion of values above and below particular values
  • skewness
    A) right skew
    B) left skew
  • right skews have the tailing end on the right
  • left skews have the tailing end on the left
  • left skews will have the mean to to the left of the median
  • right skew will have the mean the to right of the median