예제 #1
0
                                psi=np.eye(target_dim) * psi_mnw)

        aux = MatrixNormalWishart(**models_hypparams)
        models_prior.append(aux)

    gating_hypparams = dict(K=args.nb_models,
                            gammas=np.ones((args.nb_models, )),
                            deltas=np.ones((args.nb_models, )) * args.alpha)
    gating_prior = TruncatedStickBreaking(**gating_hypparams)

    ilr = BayesianMixtureOfLinearGaussians(
        gating=CategoricalWithStickBreaking(gating_prior),
        basis=[
            GaussianWithNormalWishart(basis_prior[i])
            for i in range(args.nb_models)
        ],
        models=[
            LinearGaussianWithMatrixNormalWishart(models_prior[i],
                                                  affine=args.affine)
            for i in range(args.nb_models)
        ])

    import copy
    from sklearn.utils import shuffle
    from sklearn.metrics import mean_squared_error, r2_score

    anim = []

    split_size = int(nb_train / args.nb_splits)

    mse = np.zeros((args.nb_splits, ))
예제 #2
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def _job(kwargs):
    args = kwargs.pop('arguments')
    seed = kwargs.pop('seed')

    input = kwargs.pop('train_input')
    target = kwargs.pop('train_target')

    input_dim = input.shape[-1]
    target_dim = target.shape[-1]

    # set random seed
    np.random.seed(seed)

    nb_params = input_dim
    if args.affine:
        nb_params += 1

    basis_prior = []
    models_prior = []

    # initialize Normal
    psi_nw = 1e0
    kappa = 1e-2

    # initialize Matrix-Normal
    psi_mnw = 1e0
    K = 1e-3

    for n in range(args.nb_models):
        basis_hypparams = dict(mu=np.zeros((input_dim, )),
                               psi=np.eye(input_dim) * psi_nw,
                               kappa=kappa,
                               nu=input_dim + 1)

        aux = NormalWishart(**basis_hypparams)
        basis_prior.append(aux)

        models_hypparams = dict(M=np.zeros((target_dim, nb_params)),
                                K=K * np.eye(nb_params),
                                nu=target_dim + 1,
                                psi=np.eye(target_dim) * psi_mnw)

        aux = MatrixNormalWishart(**models_hypparams)
        models_prior.append(aux)

    # define gating
    if args.prior == 'stick-breaking':
        gating_hypparams = dict(K=args.nb_models,
                                gammas=np.ones((args.nb_models, )),
                                deltas=np.ones(
                                    (args.nb_models, )) * args.alpha)
        gating_prior = TruncatedStickBreaking(**gating_hypparams)

        ilr = BayesianMixtureOfLinearGaussians(
            gating=CategoricalWithStickBreaking(gating_prior),
            basis=[
                GaussianWithNormalWishart(basis_prior[i])
                for i in range(args.nb_models)
            ],
            models=[
                LinearGaussianWithMatrixNormalWishart(models_prior[i],
                                                      affine=args.affine)
                for i in range(args.nb_models)
            ])

    else:
        gating_hypparams = dict(K=args.nb_models,
                                alphas=np.ones(
                                    (args.nb_models, )) * args.alpha)
        gating_prior = Dirichlet(**gating_hypparams)

        ilr = BayesianMixtureOfLinearGaussians(
            gating=CategoricalWithDirichlet(gating_prior),
            basis=[
                GaussianWithNormalWishart(basis_prior[i])
                for i in range(args.nb_models)
            ],
            models=[
                LinearGaussianWithMatrixNormalWishart(models_prior[i],
                                                      affine=args.affine)
                for i in range(args.nb_models)
            ])
    ilr.add_data(target, input, whiten=True)

    # Gibbs sampling
    ilr.resample(maxiter=args.gibbs_iters, progprint=args.verbose)

    for _ in range(args.super_iters):
        if args.stochastic:
            # Stochastic meanfield VI
            ilr.meanfield_stochastic_descent(maxiter=args.svi_iters,
                                             stepsize=args.svi_stepsize,
                                             batchsize=args.svi_batchsize)
        if args.deterministic:
            # Meanfield VI
            ilr.meanfield_coordinate_descent(tol=args.earlystop,
                                             maxiter=args.meanfield_iters,
                                             progprint=args.verbose)

        ilr.gating.prior = ilr.gating.posterior
        for i in range(ilr.likelihood.size):
            ilr.basis[i].prior = ilr.basis[i].posterior
            ilr.models[i].prior = ilr.models[i].posterior

    return ilr
예제 #3
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            aux = MatrixNormalWishart(**models_hypparams)
            models_prior.append(aux)

        gating_hypparams = dict(K=args.nb_models,
                                gammas=np.ones((args.nb_models, )),
                                deltas=np.ones(
                                    (args.nb_models, )) * args.alpha)
        gating_prior = TruncatedStickBreaking(**gating_hypparams)

        ilrs.append(
            BayesianMixtureOfLinearGaussians(
                gating=CategoricalWithStickBreaking(gating_prior),
                basis=[
                    GaussianWithNormalWishart(basis_prior[i])
                    for i in range(args.nb_models)
                ],
                models=[
                    LinearGaussianWithMatrixNormalWishart(models_prior[i],
                                                          affine=args.affine)
                    for i in range(args.nb_models)
                ]))

    import copy
    from sklearn.utils import shuffle
    from sklearn.metrics import mean_squared_error, r2_score

    # split data for n sequential updates and k models
    data_size = input.shape[0]
    batch_size = int(data_size / args.nb_splits)

    mse = np.zeros((args.nb_seeds, args.nb_splits))