Quantitative Investigations of Variation

• When is a normal distribution curve used?


  Foe a feature that shows continuous variation.
• What is it called if a normal distribution curve is slightly shifted to the side?

  Skewed distribution.
• What values are the same in a normal distribution curve?

  Mean, median, and mode.
• When are the mode, median, and mean different values?

  When the graph shows a skewed distribution.
• What is the standard deviation?

  A measure of the width of the normal distribution curve that gives a range of values either side of the mean.
• What is a standard deviation?


  The distance from the mean to the point where the curve changes from being convex to concave (the point of inflection).