How to add a dummy dimension?

[junpenglao]

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Order statistics in PyMC3

OK, I cooked up something that kind of work: import numpy as np import pymc3 as pm import theano.tensor as tt # data K = 5 # number of items being ranked J = 20 # number of raters yreal = np.argsort(np.random.randn(K, 1), axis=0) print(yreal) y = np.argsort(yreal + np.random.randn(K, J), axis=0) print(y) class Ordered2D(pm.distributions.transforms.ElemwiseTransform): name = "ordered" def forward(self, x): out = tt.zeros(x.shape) out = tt.inc_subtensor(out[0,:], x[0,:]…