Statistics.Descriptive
Provides basic statistics functions
Summary
| geometric_mean(list) | Calculate the geometric mean of a list |
| harmonic_mean(list) | Calculates the harmonic mean from a list |
| iqr(list) | Calculate the inter-quartile range |
| kurtosis(list) | Computes the kurtosis (Fisher) of a list |
| max(list) | Get the maximum value from a list |
| mean(list) | Calculate the mean from a list of numbers |
| median(list) | Get the median value from a list |
| min(list) | Get the minimum value from a list |
| mode(list) | Get the most frequently occuring value |
| moment(list, moment \\ 1) | Calculates the nth moment about the mean for a sample |
| percentile(list, n) | Get the nth percentile cutoff from a list |
| quartile(list, quartile) | Get the quartile cutoff value from a list |
| range(list) | Get range of data |
| skew(list) | Computes the skewness of a data set |
| start(type, args) | Callback implementation of |
| stdev(list) | Calculate the standard deviation of a list |
| sum(list) | Sum the contents of a list |
| trimmed_mean(list) | |
| trimmed_mean(list, arg2) | Calculate the trimmed mean of a list. Can specify cutoff values as a tuple, or simply choose the IQR min/max as the cutoffs |
| variance(list) | Calculate variance from a list of numbers |
| zscore(list) | Calculate a standard |
Functions
Calculate the geometric mean of a list
Geometric mean is the nth root of the product of n values
Examples
iex> Statistics.Descriptive.geometric_mean([1,2,3])
1.8171205928321397Calculates the harmonic mean from a list
Harmonic mean is the number of values divided by the sum of the reciprocal of all the values.
Examples
iex> Statistics.Descriptive.harmonic_mean([1,2,3,4,5,6,7,8,9,10,11,12,13,14,15])
4.5204836768674568Computes the kurtosis (Fisher) of a list.
Kurtosis is the fourth central moment divided by the square of the variance.
Examples
iex> Statistics.Descriptive.kurtosis([1,2,3,2,1])
-1.1530612244897964Calculate the mean from a list of numbers
Examples
iex> Statistics.Descriptive.mean([1,2,3])
2.0Get the median value from a list
Examples
iex> Statistics.Descriptive.median([1,2,3])
2
iex> Statistics.Descriptive.median([1,2,3,4])
2.5Get the most frequently occuring value
Examples
iex> Statistics.Descriptive.mode([1,2,3,2,4,5,2,6,7,2,8,9])
2Calculates the nth moment about the mean for a sample.
Generally used to calculate coefficients of skewness and kurtosis. Returns the n-th central moment as a float The denominator for the moment calculation is the number of observations, no degrees of freedom correction is done.
Examples
iex> Statistics.Descriptive.moment([1,2,3,4,5,6,7,8,9,8,7,6,5,4,3],3)
-1.3440000000000025Get the nth percentile cutoff from a list
Examples
iex> Statistics.Descriptive.percentile([1,2,3,4,5,6,7,8,9],80)
7.4
iex> Statistics.Descriptive.percentile([1,2,3,4,5,6,7,8,9],100)
9Get the quartile cutoff value from a list
responds to only first and third quartile.
Examples
iex> Statistics.Descriptive.quartile([1,2,3,4,5,6,7,8,9],:first)
3
iex> Statistics.Descriptive.quartile([1,2,3,4,5,6,7,8,9],:third)
7Computes the skewness of a data set.
For normally distributed data, the skewness should be about 0. A skewness value > 0 means that there is more weight in the left tail of the distribution.
Examples
iex> Statistics.Descriptive.skew([1,2,3,2,1])
0.3436215967445454Callback implementation of :application.start/2.
Calculate the standard deviation of a list
Examples
iex> Statistics.Descriptive.stdev([1,2])
0.5Calculate the trimmed mean of a list. Can specify cutoff values as a tuple, or simply choose the IQR min/max as the cutoffs
Examples
iex> Statistics.Descriptive.trimmed_mean([1,2,3],{1,3}) 2.0 iex> Statistics.Descriptive.trimmed_mean([1,2,3,4,5,5,6,6,7,7,8,8,10,11,12,13,14,15], :iqr) 7.3
Calculate variance from a list of numbers
Examples
iex> Statistics.Descriptive.variance([1,2,3,4])
1.25
iex> Statistics.Descriptive.variance([55,56,60,65,54,51,39])
56.48979591836735Calculate a standard z score for each item in a list
Examples
iex> Statistics.Descriptive.zscore([3,2,3,4,5,6,5,4,3])
[-0.7427813527082074, -1.5784103745049407, -0.7427813527082074,
0.09284766908852597, 0.9284766908852594, 1.7641057126819928,
0.9284766908852594, 0.09284766908852597, -0.7427813527082074]