Measurements Flashcards
How would you calculate the mean?
Add all the numbers ÷ by number of numbers
What are the strengths of using the mean?
Uses all data values.
What are the weaknesses of using the mean?
Greatly affected by extremes.
May not be an actual meaningful value.
How would you calculate the mode?
Most commonly occurring value
What are the strengths of using the mode?
Not affected by outliers
Can be collected for qualitative data.
What are the weaknesses of using the mode?
Not all data sets have a modal value.
Some data has more than one modal value.
How would you calculate the median?
Middle of data set when in rank order
What are the strengths of using the median?
Can be determined for all data types.
Not overly influenced by extremes.
What are the weaknesses of using the median?
Data must be in rank order.
How would you calculate the range?
Highest - lowest
What are the strengths of using the range?
Easy to calculate and understand.
What are the weaknesses of using the range?
Only uses extremes (not all data), so very affected by them.
Only shows maximum spread not shape.
How would you calculate the interquartile range?
Upper quartile - lower quartile
What are the strengths of using the interquartile range?
Ignores extremes/outliers so more stable than range.
What are the weaknesses of using the interquartile range?
Doesn’t use all data - ignores 50% of data points.
