hypothesis testing

pval_calculator.py

# -*- coding: utf-8 -*-
from functools import reduce
from sys import argv

def partial_fact(tries, success):
    m = range(tries - success + 1, tries + 1)
    return reduce((lambda x,y: x*y), m)
    
def fact(n):
    return reduce((lambda x,y: x*y), range(1, n+1))
    
def combs(tries, success):
    return partial_fact(tries, success)/fact(success)
    
def pval(tries, success):
    all_combs = 2**tries
    return combs(tries, success) / all_combs
    
if __name__ == "__main__":
    tries = int(argv[1])
    success = int(argv[2])
    print("probability of random prediction is: %.3f" % pval(tries, success))