statsmodels.tools.tools.isestimable¶
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statsmodels.tools.tools.
isestimable
(C, D)[source]¶ True if (Q, P) contrast C is estimable for (N, P) design D
From an Q x P contrast matrix C and an N x P design matrix D, checks if the contrast C is estimable by looking at the rank of
vstack([C,D])
and verifying it is the same as the rank of D.Parameters: C : (Q, P) array-like
contrast matrix. If C has is 1 dimensional assume shape (1, P)
D: (N, P) array-like
design matrix
Returns: tf : bool
True if the contrast C is estimable on design D
Examples
>>> D = np.array([[1, 1, 1, 0, 0, 0], ... [0, 0, 0, 1, 1, 1], ... [1, 1, 1, 1, 1, 1]]).T >>> isestimable([1, 0, 0], D) False >>> isestimable([1, -1, 0], D) True