def Likelihood(self, data, hypo):
"""Computes the likelihood of the data under the hypothesis.
Evaluates the Poisson PMF for lambda and k.
hypo: elapsed time since the last train
data: tuple of arrival rate and number of passengers
"""
x = hypo
lam, k = data
like = thinkstats2.EvalPoissonPmf(k, lam * x)
return like
def Likelihood(self, data, hypo):
"""Computes the likelihood of the data under the hypothesis.
Evaluates the Poisson PMF for lambda and k.
hypo: arrival rate in passengers per second
data: tuple of elapsed_time and number of passengers
"""
lam = hypo
x, k = data
like = thinkstats2.EvalPoissonPmf(k, lam * x)
return like
def testEvalPoissonPmf(self):
p = thinkstats2.EvalPoissonPmf(2, 1)
self.assertAlmostEqual(p, 0.1839397205)
