mvem.stats.multivariate_norm

mvem.stats.multivariate_norm.cdf

mvem.stats.multivariate_norm.cdf(x, mean, cov, allow_singular=False, maxpts=1000000, abseps=1e-05, releps=1e-05)[source]

Cumulative density function of the multivariate normal distribution.

Parameters
  • x (np.ndarray) – An array of shape (n, p) containing n observations of some p-variate data with n > p.

  • mean (np.ndarray) – The mean of the normal distribution. A parameter with shape (p,).

  • cov (np.ndarray) – The covariance of the normal distribution. A positive semi-definite array with shape (p, p).

  • allow_singular (bool, optional) – Whether to allow a singular matrix. Defaults to False.

  • maxpts (int, optional) – The maximum number of points to use for integration.

  • abseps (float, optional) – The absolute error tolerance. Defaults to 1e-5.

  • releps (float, optional) – The relative error tolerance. Defaults 1e-5.

Returns

The cumulative density given all observations and parameters.

Return type

float

mvem.stats.multivariate_norm.fit

mvem.stats.multivariate_norm.fit(X, return_loglike=False)[source]

Estimate the parameters of the multivariate normal distribution using maximum likelihood estimates.

Parameters
  • x (np.ndarray) – An array of shape (n, p) containing n observations of some p-variate data with n > p.

  • return_loglike (np.ndarray, optional) – Return a list of log-likelihood values at each iteration. Defaults to False.

Returns

The fitted parameters (<array> mu, <array> sigma). Also returns a list of log-likelihood values at each iteration of the EM algorithm if return_loglike=True.

Return type

tuple

mvem.stats.multivariate_norm.logcdf

mvem.stats.multivariate_norm.logcdf(x, mean, cov, allow_singular=False, maxpts=1000000, abseps=1e-05, releps=1e-05)[source]

Log-cumulative density function of the multivariate normal distribution.

Parameters
  • x (np.ndarray) – An array of shape (n, p) containing n observations of some p-variate data with n > p.

  • mean (np.ndarray) – The mean of the normal distribution. A parameter with shape (p,).

  • cov (np.ndarray) – The covariance of the normal distribution. A positive semi-definite array with shape (p, p).

  • allow_singular (bool, optional) – Whether to allow a singular matrix. Defaults to False.

  • maxpts (int, optional) – The maximum number of points to use for integration.

  • abseps (float, optional) – The absolute error tolerance. Defaults to 1e-5.

  • releps (float, optional) – The relative error tolerance. Defaults 1e-5.

Returns

The log-cumulative density given all observations and parameters.

Return type

float

mvem.stats.multivariate_norm.loglike

mvem.stats.multivariate_norm.loglike(x, mean, cov, allow_singular=False)[source]

Log-likelihood function of the multivariate normal distribution.

Parameters
  • x (np.ndarray) – An array of shape (n, p) containing n observations of some p-variate data with n > p.

  • mean (np.ndarray) – The mean of the normal distribution. A parameter with shape (p,).

  • cov (np.ndarray) – The covariance of the normal distribution. A positive semi-definite array with shape (p, p).

  • allow_singular (bool, optional) – Whether to allow a singular matrix. Defaults to False.

Returns

The log-likelihood for given all observations and parameters.

Return type

float

mvem.stats.multivariate_norm.logpdf

mvem.stats.multivariate_norm.logpdf(x, mean, cov, allow_singular=False)[source]

Log-probability density function of the multivariate normal distribution.

Parameters
  • x (np.ndarray) – An array of shape (n, p) containing n observations of some p-variate data with n > p.

  • mean (np.ndarray) – The mean of the normal distribution. A parameter with shape (p,).

  • cov (np.ndarray) – The covariance of the normal distribution. A positive semi-definite array with shape (p, p).

  • allow_singular (bool, optional) – Whether to allow a singular matrix. Defaults to False.

Returns

The log-density at each observation.

Return type

np.ndarray with shape (n,).

mvem.stats.multivariate_norm.mean

mvem.stats.multivariate_norm.mean(mean, cov)[source]

Mean function of the multivariate normal distribution.

Parameters
  • mean (np.ndarray) – The mean of the normal distribution. A parameter with shape (p,).

  • cov (np.ndarray) – The covariance of the normal distribution. A positive semi-definite array with shape (p, p).

Returns

The mean of the specified distribution.

Return type

np.ndarray with shape (p,).

mvem.stats.multivariate_norm.pdf

mvem.stats.multivariate_norm.pdf(x, mean, cov, allow_singular=False)[source]

Probability density function of the multivariate normal distribution.

Parameters
  • x (np.ndarray) – An array of shape (n, p) containing n observations of some p-variate data with n > p.

  • mean (np.ndarray) – The mean of the normal distribution. A parameter with shape (p,).

  • cov (np.ndarray) – The covariance of the normal distribution. A positive semi-definite array with shape (p, p).

  • allow_singular (bool, optional) – Whether to allow a singular matrix. Defaults to False.

Returns

The density at each observation.

Return type

np.ndarray with shape (n,).

mvem.stats.multivariate_norm.rvs

mvem.stats.multivariate_norm.rvs(mean, cov, size=1, random_state=None)[source]

Random number generator of the multivariate normal distribution.

Parameters
  • mean (np.ndarray) – The mean of the normal distribution. A parameter with shape (p,).

  • cov (np.ndarray) – The covariance of the normal distribution. A positive semi-definite array with shape (p, p).

  • size (int, optional) – The number of samples to draw. Defaults to 1.

  • random_state (None, int, np.random.RandomState, np.random.Generator, optional) – Used for drawing random variates. Defaults to None.

Returns

The random p-variate numbers generated.

Return type

np.ndarray with shape (n, p).

mvem.stats.multivariate_norm.var

mvem.stats.multivariate_norm.var(mean, cov)[source]

Variance function of the multivariate normal distribution.

Parameters
  • mean (np.ndarray) – The mean of the normal distribution. A parameter with shape (p,).

  • cov (np.ndarray) – The covariance of the normal distribution. A positive semi-definite array with shape (p, p).

Returns

The variance of the specified distribution.

Return type

np.ndarray with shape (p,).