示例#1
0
    def test_pdf(self):
        """Test pdf method."""

        skewt = SkewStudent()

        num = 50
        arg = np.linspace(-1, 1, num)
        pdf = skewt.pdf(arg)

        self.assertEqual(pdf.shape[0], num)
        self.assertIsInstance(skewt.pdf(0), float)
示例#2
0
    def test_pdf(self):
        """Test pdf method."""

        skewt = SkewStudent()

        num = 50
        arg = np.linspace(-1, 1, num)
        pdf = skewt.pdf(arg)

        self.assertEqual(pdf.shape[0], num)
        self.assertIsInstance(skewt.pdf(0), float)
示例#3
0
    def test_compare_with_t(self):
        """Compare with standard t distribution."""

        eta = 5
        skewt = SkewStudent(eta=eta, lam=0)
        scale = 1/(eta/(eta-2))**.5
        standt = t(eta, scale=scale)
        arg = np.linspace(-2, 2, 100)

        np.testing.assert_array_almost_equal(skewt.pdf(arg), standt.pdf(arg))
        np.testing.assert_array_almost_equal(skewt.cdf(arg), standt.cdf(arg))

        arg = np.linspace(.01, .99, 100)

        np.testing.assert_array_almost_equal(skewt.ppf(arg), standt.ppf(arg))
示例#4
0
    def test_compare_with_t(self):
        """Compare with standard t distribution."""

        eta = 5
        skewt = SkewStudent(eta=eta, lam=0)
        scale = 1 / (eta / (eta - 2))**.5
        standt = t(eta, scale=scale)
        arg = np.linspace(-2, 2, 100)

        np.testing.assert_array_almost_equal(skewt.pdf(arg), standt.pdf(arg))
        np.testing.assert_array_almost_equal(skewt.cdf(arg), standt.cdf(arg))

        arg = np.linspace(.01, .99, 100)

        np.testing.assert_array_almost_equal(skewt.ppf(arg), standt.ppf(arg))