Description
a) An option to choose the calculation method for quartiles from one of the following
algorithms. The algorithms can also be found on the Wikipedia Page on quartiles
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Excel QUARTILE.EXC() Function / Wikipedia method 1
Use the median to divide the ordered data set into two halves.
o If there is an odd number of data points in the original ordered data set, do not
include the median (the central value in the ordered list) in either half.
o If there is an even number of data points in the original ordered data set, split this
data set exactly in half.
The lower quartile value is the median of the lower half of the data. The upper quartile
value is the median of the upper half of the data. -
Excel QUARTILE.INC() Function / Wikipedia method 2
Use the median to divide the ordered data set into two halves.
o If there are an odd number of data points in the original ordered data set, include the
median (the central value in the ordered list) in both halves.
o If there are an even number of data points in the original ordered data set, split this data
set exactly in half.
The lower quartile value is the median of the lower half of the data. The upper quartile value
is the median of the upper half of the data. -
Matlab algorithm / Wikipedia method 3:
i. If there are even numbers of data points, then Method 3 is the same as either method
above
ii. If there are (4n+1) data points, then the lower quartile is 25% of the nth data value plus
75% of the (n+1)th data value; the upper quartile is 75% of the (3n+1)th data point plus
25% of the (3n+2)th data point.
iii. If there are (4n+3) data points, then the lower quartile is 75% of the (n+1)th data value
plus 25% of the (n+2)th data value; the upper quartile is 25% of the (3n+2)th data point
plus 75% of the (3n+3)th data point.
b) Plotly should offer an option to manually provide the minimum, median and maximum value as well as the quartiles for the Box plot. -> #1059