The SampleStatistics class provides methods for data manipulation and calculating such simple sample statistics of empirical data as moments, central moments, min, max. Samples are objects of classes which have a java Collection interface (e.g. ArrayList, Vector etc.).
Table 20.43. Methods for samples and sample statistics
| Method | Description |
| addSample(_sample) | adds the data sample _sample to the sample |
| clear() | clears the data sample |
| computeCentralMoment(int p) | computes the central moment of order p of the sample |
| computeMoment(int p) | computes the moment of order p of the sample |
| computeSum() | computes the sum of the elements of the sample |
| getMax() | finds the maximum of the elements of the sample |
| getMin() | computes minimum of the elements of the sample |
| setSample() | sets a data sample |
Example 20.6. Sample statistics of empirical data
from biz.sc.math.distributions import *
from biz.sc.math.distributions.continuous import *
from java.util import Arrays
from random import *
_min = 0.1
_max = 0.3
rand=Random()
rand.seed(10)
_uni = UniformDistribution(_min, _max)
vector = []
for i in range (100):
vector.append(rand.random())
sample = SampleStatistics(Arrays.asList(vector))
print 'Min: %1.4f' % sample.getMin()
print 'Max: %1.4f' % sample.getMax()
print 'Moment: %1.4f' % sample.computeMoment(3)
Output:
Min: 0.0011 Max: 0.9988 Moment: 0.5562