data_model.kappa = -7.0
covariates = ['x_%d' % i for i in range(5)]
for covariate in covariates:
    data_model.beta[covariate] = normal(0, 1.0)

    x_node = normal(0, 1.0, N)
    def f_x(i_1, i_2):
        return abs(x_node[i_1] - x_node[i_2]) < 0.3
    net.new_edge_covariate(covariate).from_binary_function_ind(f_x)
net.generate(data_model)
net.offset_extremes()
net.show()
print 'True theta_0: %.2f' % data_model.beta['x_0']

# Initialize the fit model; specify which covariates it should have terms for
fit_model = NonstationaryLogistic()
for covariate in covariates:
    fit_model.beta[covariate] = None

# Set up random subnetwork generator, and run fitting experiments
gen = RandomSubnetworks(net, (200, 200))
for rep in range(5):
    subnet = gen.sample()

    fit_model.fit(subnet)
    print 'Estimated theta_0: %.2f' % fit_model.beta['x_0']

    fit_model.confidence(subnet, n_bootstrap = 5)
    ci = fit_model.conf['x_0']['normal']
    print 'Normal CI for theta_0: (%.2f, %.2f)' % ci
Exemplo n.º 2
0
    c_results = s_results.copy()
    c_results.title = 'Conditional fit'
    all_results['c'] = c_results


def initialize(s, f):
    if params['initialize_true_z']:
        s.node_covariates['z'][:] = s.node_covariates['z_true'][:]
    else:
        s.node_covariates['z'][:] = np.random.randint(0, params['fit_K'], s.N)


for sub_size in params['sub_sizes']:
    print 'subnetwork size = %d' % sub_size

    gen = RandomSubnetworks(net, sub_size)
    for rep in range(params['num_reps']):
        subnet = gen.sample()
        data_model.match_kappa(subnet, params['kappa_target'])
        subnet.generate(data_model)

        initialize(subnet, fit_model)
        fit_model.fit(subnet,
                      params['cycles'],
                      params['sweeps'],
                      verbose=params['verbose'])
        s_results.record(sub_size, rep, subnet, data_model, fit_model)
        print

        if params['fit_conditional']:
            initialize(subnet, fit_model)
Exemplo n.º 3
0
    c_results.title = 'Conditional fit'
    all_results['c'] = c_results


def initialize(s, f):
    if params['initialize_true_z']:
        s.node_covariates['z'][:] = s.node_covariates['z_true'][:]
    else:
        s.node_covariates['z'][:] = np.random.randint(0, params['fit_K'], s.N)


for sub_size in params['sub_sizes']:
    size = (sub_size, sub_size)
    print 'subnetwork size = %s' % str(size)

    gen = RandomSubnetworks(net, size)
    for rep in range(params['num_reps']):
        subnet = gen.sample(as_network=True)
        data_model.match_kappa(subnet, params['kappa_target'])
        subnet.generate(data_model)

        initialize(subnet, fit_model)
        fit_model.fit(subnet,
                      params['cycles'],
                      params['sweeps'],
                      verbose=params['verbose'])
        s_results.record(size, rep, subnet, data_model, fit_model)
        print

        if params['fit_conditional']:
            initialize(subnet, fit_model)
Exemplo n.º 4
0
for covariate in covariates:
    data_model.beta[covariate] = normal(0, 1.0)

    x_node = normal(0, 1.0, N)

    def f_x(i_1, i_2):
        return abs(x_node[i_1] - x_node[i_2]) < 0.3

    net.new_edge_covariate(covariate).from_binary_function_ind(f_x)
net.generate(data_model)
net.offset_extremes()
net.show()
print 'True theta_0: %.2f' % data_model.beta['x_0']

# Initialize the fit model; specify which covariates it should have terms for
fit_model = NonstationaryLogistic()
for covariate in covariates:
    fit_model.beta[covariate] = None

# Set up random subnetwork generator, and run fitting experiments
gen = RandomSubnetworks(net, (200, 200))
for rep in range(5):
    subnet = gen.sample()

    fit_model.fit(subnet)
    print 'Estimated theta_0: %.2f' % fit_model.beta['x_0']

    fit_model.confidence(subnet, n_bootstrap=5)
    ci = fit_model.conf['x_0']['normal']
    print 'Normal CI for theta_0: (%.2f, %.2f)' % ci
    data_model.beta[covariate] = normal(0, 1.0)

    x_node = normal(0, 1.0, N)

    def f_x(i_1, i_2):
        return abs(x_node[i_1] - x_node[i_2]) < 0.6

    net.new_edge_covariate(covariate).from_binary_function_ind(f_x)
net.generate(data_model)
net.offset_extremes()
net.show()
print 'True theta_0: %.2f' % data_model.beta['x_0']

# Initialize the fit model; specify which covariates it should have terms for
fit_model = NonstationaryLogistic()
for covariate in covariates:
    fit_model.beta[covariate] = None

# Set up random subnetwork generator, and run fitting experiments
gen = RandomSubnetworks(net, (40, 40))
for rep in range(5):
    subnet = gen.sample()

    fit_model.fit_brazzale(subnet, 'x_0')
    print 'Estimated theta_0: %.2f' % fit_model.beta['x_0']

    fit_model.confidence_boot(subnet, n_bootstrap=10)
    cis = fit_model.conf['x_0']
    print 'Brazzale CI for theta_0: (%.2f, %.2f)' % cis['brazzale']
    print 'Pivotal CI for theta_0: (%.2f, %.2f)' % cis['pivotal']
        s.node_covariates['z'][:] = np.random.randint(0, params['fit_K'], s.N)
        
    if offset_extremes:
        s.offset_extremes()
    else:
        s.initialize_offset()
        
    for i in range(subnet.N):
        # TODO: Track down why -np.inf causes problems with CMLE...
        subnet.offset[i,i] = -20.0
        
for sub_size in params['sub_sizes']:
    size = (sub_size, sub_size)
    print 'subnetwork size = %s' % str(size)
    
    gen = RandomSubnetworks(net, size, method = params['sampling'])
    for rep in range(params['num_reps']):
        subnet = gen.sample(as_network = True)
        
        initialize(subnet, fit_model, offset_extremes = False)
        fit_base_model.fit = fit_base_model.fit_convex_opt
        fit_model.ignore_inner_offset = False
        fit_model.fit(subnet, params['cycles'], params['sweeps'])
        s_results.record(size, rep, subnet, fit_model = fit_model)
        print 'S: ', fit_model.Theta
        print

        if params['fit_conditional']:
            initialize(subnet, fit_model, offset_extremes = False)
            fit_base_model.fit = fit_base_model.fit_conditional
            fit_model.ignore_inner_offset = True
Exemplo n.º 7
0
def do_experiment(params):
    if params['dump_fits'] and params['load_fits']:
        print 'Warning: simultaneously dumping and loading is a bad idea.'

    if params['dump_fits']:
        fits = []

    if params['load_fits']:
        with open(params['load_fits'], 'r') as fits_file:
            loaded_params_pick, loaded_fits = json.load(fits_file)

        loaded_params = dict([(k, unpick(v)) for (k, v) in loaded_params_pick])

        # Compare on parameters that control data generation and inference
        run_params = [
            'N', 'B', 'theta_sd', 'theta_fixed', 'alpha_unif_sd',
            'alpha_norm_sd', 'alpha_gamma_sd', 'cov_unif_sd', 'cov_norm_sd',
            'cov_disc_sd', 'kappa_target', 'pre_offset', 'post_fit',
            'fit_nonstationary', 'fit_method', 'num_reps', 'is_T', 'sampling',
            'sub_sizes_r', 'sub_sizes_c', 'random_seed'
        ]

        for p in run_params:
            if not np.all(loaded_params[p] == params[p]):
                print 'Warning: load mismatch on', p

    # Set random seed for reproducible output
    seed = Seed(params['random_seed'])

    # Initialize full network
    arr = Network(params['N'])

    # Generate node-level propensities to extend and receive edges
    if params['alpha_norm_sd'] > 0.0:
        alpha_norm(arr, params['alpha_norm_sd'])
    elif params['alpha_unif_sd'] > 0.0:
        alpha_unif(arr, params['alpha_unif_sd'])
    elif params['alpha_gamma_sd'] > 0.0:
        # Choosing location somewhat arbitrarily to give unit skewness
        alpha_gamma(arr, 4.0, params['alpha_gamma_sd'])
    else:
        alpha_zero(arr)

    # Generate covariates and associated coefficients
    data_model = NonstationaryLogistic()
    covariates = []
    for b in range(params['B']):
        name = 'x_%d' % b
        covariates.append(name)

        if name in params['theta_fixed']:
            data_model.beta[name] = params['theta_fixed'][name]
        else:
            data_model.beta[name] = np.random.normal(0, params['theta_sd'])

        if params['cov_unif_sd'] > 0.0:
            c = np.sqrt(12) / 2

            def f_x(i_1, i_2):
                return np.random.uniform(-c * params['cov_unif_sd'],
                                         c * params['cov_unif_sd'])
        elif params['cov_norm_sd'] > 0.0:

            def f_x(i_1, i_2):
                return np.random.normal(0, params['cov_norm_sd'])
        elif params['cov_disc_sd'] > 0.0:

            def f_x(i_1, i_2):
                return (params['cov_disc_sd'] *
                        (np.sign(np.random.random() - 0.5)))
        else:
            print 'Error: no covariate distribution specified.'
            sys.exit()

        arr.new_edge_covariate(name).from_binary_function_ind(f_x)

    # Generate large network, if necessary
    if not params['sampling'] == 'new':
        data_model.match_kappa(arr, params['kappa_target'])
        arr.generate(data_model)

    if params['fit_nonstationary']:
        fit_model = NonstationaryLogistic()
    else:
        fit_model = StationaryLogistic()
    for c in covariates:
        fit_model.beta[c] = None

    # Set up recording of results from experiment
    results = Results(params['sub_sizes_r'],
                      params['sub_sizes_c'],
                      params['num_reps'],
                      interactive=params['interactive'])
    add_array_stats(results)
    if params['plot_sig']:
        from scipy.stats import chi2
        crit = lambda dof: -0.5 * chi2.ppf(0.95, dof)

        umle_f = lambda n, f: f.nll(n, ignore_offset=True)
        umle_d = lambda n, d: d.nll(n, ignore_offset=True)
        umle_n = lambda n: NonstationaryLogistic().nll(n, ignore_offset=True)
        results.new('UMLE F-N', 'nm', lambda n, d, f: umle_f(n, f) - umle_n(n))
        results.new('UMLE F-D', 'nm',
                    lambda n, d, f: umle_f(n, f) - umle_d(n, d))

        cmle_a_f = lambda n, f: acnll(n.as_dense(),
                                      np.exp(f.edge_probabilities(n)))
        cmle_a_d = lambda n, d: acnll(n.as_dense(),
                                      np.exp(d.edge_probabilities(n)))
        cmle_a_n = lambda n: acnll(n.as_dense(), np.ones_like(n.as_dense()))
        results.new('CMLE-A F-N', 'nm',
                    lambda n, d, f: cmle_a_f(n, f) - cmle_a_n(n))
        results.new('CMLE-A F-D', 'nm',
                    lambda n, d, f: cmle_a_f(n, f) - cmle_a_d(n, d))

        cmle_is_f = lambda n, f: f.fit_conditional(n, evaluate=True, T=50)
        cmle_is_d = lambda n, d: d.fit_conditional(n, evaluate=True, T=50)
        cmle_is_n = lambda n: NonstationaryLogistic().fit_conditional(
            n, evaluate=True, T=50)
        results.new('CMLE-IS F-N', 'nm',
                    lambda n, d, f: cmle_is_f(n, f) - cmle_is_n(n))
        results.new('CMLE-IS F-D', 'nm',
                    lambda n, d, f: cmle_is_f(n, f) - cmle_is_d(n, d))

        c_cmle_f = lambda n, f: f.fit_c_conditional(n, evaluate=True)
        c_cmle_d = lambda n, d: d.fit_c_conditional(n, evaluate=True)
        c_cmle_n = lambda n: NonstationaryLogistic().fit_c_conditional(
            n, evaluate=True)
        results.new('C-CMLE F-N', 'nm',
                    lambda n, d, f: c_cmle_f(n, f) - c_cmle_n(n))
        results.new('C-CMLE F-D', 'nm',
                    lambda n, d, f: c_cmle_f(n, f) - c_cmle_d(n, d))

        results.new('UMLE sig.', 'dof', lambda M, N, B: crit((M - 1) +
                                                             (N - 1) + 1 + B))
        results.new('CMLE sig.', 'dof', lambda M, N, B: crit(B))
        results.new('C-CMLE sig.', 'dof', lambda M, N, B: crit((M - 1) + B))

    if params['sampling'] == 'new':
        results.new('Subnetwork kappa', 'm', lambda d, f: d.kappa)

    def true_est_theta_c(c):
        return (lambda d, f: d.beta[c]), (lambda d, f: f.beta[c])

    for c in covariates:
        # Need to do this hackily to avoid for-loop/lambda-binding weirdness.
        f_true, f_est = true_est_theta_c(c)
        results.new('True theta_{%s}' % c, 'm', f_true)
        results.new('Est. theta_{%s}' % c, 'm', f_est)
    if params['pre_offset'] or params['post_fit']:
        results.new('# Active', 'n',
                    lambda n: np.isfinite(n.offset.matrix()).sum())
    else:
        results.new('# Active', 'n', lambda n: n.M * n.N)
    if params['fisher_information']:

        def info_theta_c(c):
            def f_info_theta_c(d, f):
                return d.I_inv['theta_{%s}' % c]

            return f_info_theta_c

        for c in covariates:
            results.new('Info theta_{%s}' % c, 'm', info_theta_c(c))
    if params['baseline']:

        def rel_mse_p_ij(n, d, f):
            P = d.edge_probabilities(n)
            return rel_mse(f.edge_probabilities(n), f.baseline(n), P)

        results.new('Rel. MSE(P_ij)', 'nm', rel_mse_p_ij)
        if not (params['pre_offset'] or params['post_fit']):

            def rel_mse_logit_p_ij(n, d, f):
                logit_P = d.edge_probabilities(n, logit=True)
                logit_Q = f.baseline_logit(n)
                return rel_mse(f.edge_probabilities(n, logit=True), logit_Q,
                               logit_P)

            results.new('Rel. MSE(logit P_ij)', 'nm', rel_mse_logit_p_ij)

    if params['fit_method'] in [
            'convex_opt', 'conditional', 'c_conditional', 'irls',
            'conditional_is'
    ]:
        results.new('Wall time (sec.)', 'm',
                    lambda d, f: f.fit_info['wall_time'])
    if params['fit_method'] in ['convex_opt', 'conditional', 'conditional_is']:

        def work(f):
            w = 0
            for work_type in ['nll_evals', 'grad_nll_evals', 'cnll_evals']:
                if work_type in f.fit_info:
                    w += f.fit_info[work_type]
            return w

        results.new('Work', 'm', lambda d, f: work(f))
        results.new('||ET_final - T||_2', 'm',
                    lambda d, f: l2(f.fit_info['grad_nll_final']))

    for sub_size in zip(results.M_sizes, results.N_sizes):
        print 'subnetwork size =', sub_size

        if params['sampling'] == 'new':
            gen = RandomSubnetworks(arr, sub_size)
        else:
            gen = RandomSubnetworks(arr, sub_size, method=params['sampling'])

        for rep in range(params['num_reps']):
            seed.next()
            sub = gen.sample()

            if params['fisher_information']:
                data_model.fisher_information(sub)

            if params['sampling'] == 'new':
                data_model.match_kappa(sub, params['kappa_target'])
                sub.generate(data_model)

            if params['load_fits']:
                fit, loaded_fits = loaded_fits[0], loaded_fits[1:]
                fit_model.beta = unpick(fit['theta'])
                if params['fix_broken_cmle_is']:
                    for b_n in fit_model.beta:
                        fit_model.beta[b_n] += 0.1474
                if 'alpha' in fit:
                    sub.row_covariates['alpha_out'] = unpick(fit['alpha'])
                if 'beta' in fit:
                    sub.col_covariates['alpha_in'] = unpick(fit['beta'])
                if 'kappa' in fit:
                    fit_model.kappa = fit['kappa']
                if 'offset' in fit:
                    sub.offset = unpick(fit['offset'])
                if 'fit_info' in fit:
                    fit_model.fit_info = unpick(fit['fit_info'])
            else:
                if params['pre_offset']:
                    sub.offset_extremes()

                if params['fit_method'] == 'convex_opt':
                    fit_model.fit_convex_opt(sub, verbose=params['verbose'])
                elif params['fit_method'] == 'irls':
                    fit_model.fit_irls(sub, verbose=params['verbose'])
                elif params['fit_method'] == 'logistic':
                    fit_model.fit_logistic(sub)
                elif params['fit_method'] == 'logistic_l2':
                    fit_model.fit_logistic_l2(sub, prior_precision=1.0)
                elif params['fit_method'] == 'conditional':
                    fit_model.fit_conditional(sub, verbose=params['verbose'])
                elif params['fit_method'] == 'conditional_is':
                    fit_model.fit_conditional(sub,
                                              T=params['is_T'],
                                              verbose=params['verbose'])
                elif params['fit_method'] == 'c_conditional':
                    fit_model.fit_c_conditional(sub, verbose=params['verbose'])
                elif params['fit_method'] == 'composite':
                    fit_model.fit_composite(sub,
                                            T=100,
                                            verbose=params['verbose'])
                elif params['fit_method'] == 'brazzale':
                    fit_model.fit_brazzale(sub)
                elif params['fit_method'] == 'saddlepoint':
                    fit_model.fit_saddlepoint(sub)
                elif params['fit_method'] == 'none':
                    pass

                if params['post_fit']:
                    sub.offset_extremes()
                    fit_model.fit_convex_opt(sub, fix_beta=True)

                if params['dump_fits']:
                    fit = {}
                    fit['theta'] = pick(fit_model.beta)
                    if 'alpha_out' in sub.row_covariates:
                        fit['alpha'] = pick(sub.row_covariates['alpha_out'])
                    if 'alpha_in' in sub.row_covariates:
                        fit['beta'] = pick(sub.col_covariates['alpha_in'])
                    if not fit_model.kappa is None:
                        fit['kappa'] = fit_model.kappa
                    if not sub.offset is None:
                        sub.offset.dirty()
                        fit['offset'] = pick(sub.offset)
                    if not fit_model.fit_info is None:
                        fit['fit_info'] = pick(fit_model.fit_info)

                    fits.append(fit)

            if params['find_good'] > 0:
                abs_err = abs(fit_model.beta['x_0'] - data_model.beta['x_0'])
                if abs_err < params['find_good']:
                    print abs_err

                    sub.offset = None
                    fit_model.fit_conditional(sub, T=1000, verbose=True)
                    print fit_model.beta['x_0']
                    print fit_model.fit_info

                    f = file('goodmat.mat', 'wb')
                    import scipy.io
                    Y = np.array(sub.as_dense(), dtype=np.float)
                    X = sub.edge_covariates['x_0'].matrix()
                    scipy.io.savemat(f, {'Y': Y, 'X': X})
                    sys.exit()

            if params['find_bad'] > 0:
                abs_err = abs(fit_model.beta['x_0'] - data_model.beta['x_0'])
                if abs_err > params['find_bad']:
                    print abs_err

                    sub.offset = None
                    fit_model.fit_conditional(sub, T=1000, verbose=True)
                    print fit_model.beta['x_0']
                    print fit_model.fit_info

                    f = file('badmat.mat', 'wb')
                    import scipy.io
                    Y = np.array(sub.as_dense(), dtype=np.float)
                    X = sub.edge_covariates['x_0'].matrix()
                    scipy.io.savemat(f, {'Y': Y, 'X': X})
                    sys.exit()

            results.record(sub_size, rep, sub, data_model, fit_model)

            if params['verbose']:
                print

    if params['dump_fits']:
        with open(params['dump_fits'], 'w') as outfile:
            json.dump(([(p, pick(params[p])) for p in params], fits), outfile)

    # Compute beta MSEs
    covariate_naming = []
    for c in covariates:
        mse_name = 'MSE(theta_{%s})' % c
        true_name = 'True theta_{%s}' % c
        est_name = 'Est. theta_{%s}' % c
        results.estimate_mse(mse_name, true_name, est_name)
        covariate_naming.append((c, mse_name, true_name, est_name))

    # Report parameters for the run
    print 'Parameters:'
    for field in params:
        print '%s: %s' % (field, str(params[field]))

    # Should not vary between runs with the same seed and same number
    # of arrays tested
    seed.final()

    results.summary()

    return results, covariate_naming
Exemplo n.º 8
0
# Initialize the fit model; specify which covariates it should have terms for
fit_model = StationaryLogistic()
for covariate in covariates:
    fit_model.beta[covariate] = None

# Set up plotting
f = plt.figure()
ax = f.add_subplot(1, 1, 1, aspect = 'equal')
ax.set_title('95% confidence regions')
ax.set_xlim(data_model.beta['x_1'] - 2.0, data_model.beta['x_1'] + 2.0)
ax.set_ylim(data_model.beta['x_2'] - 2.0, data_model.beta['x_2'] + 2.0)
ax.set_xlabel('beta_1')
ax.set_ylabel('beta_2')

# Set up random subnetwork generator, and run fitting experiments
gen = RandomSubnetworks(net, (sub_N, sub_N))
for rep in range(10):
    subnet = gen.sample()

    fit_model.fit_logistic_l2(subnet, prior_precision = 1.0,
                              variance_covariance = True)
    print 'Estimated beta_1: %.2f' % fit_model.beta['x_1']
    
    m = np.array([fit_model.beta['x_1'], fit_model.beta['x_2']])
    vc = fit_model.variance_covariance
    S = np.array([[vc[('x_1','x_1')], vc['x_1','x_2']],
                  [vc[('x_2','x_1')], vc['x_2','x_2']]])
    draw_confidence(ax, m, S)
plt.show()
for method_name in params['sampling_methods']:
    results = Results(params['sub_sizes'],
                      params['sub_sizes'],
                      params['num_reps'],
                      title=method_name)
    add_array_stats(results, network=True)
    results.new('# Active', 'n',
                lambda n: np.isfinite(n.offset.matrix()).sum())
    results_by_method[method_name] = results

for sub_size in params['sub_sizes']:
    size = (sub_size, sub_size)
    print 'subnetwork size = %s' % str(size)

    generators = \
      { 'random_node': RandomSubnetworks(net, size, method = 'node'),
        'random_edge': RandomSubnetworks(net, size, method = 'edge'),
        'link_trace': RandomSubnetworks(net, size, method = 'link'),
        'link_trace_f': RandomSubnetworks(net, size, method = 'link_f') }
    for generator in generators:
        if not generator in params['sampling_methods']: continue
        print generator
        for rep in range(params['num_reps']):
            subnet = generators[generator].sample(as_network=True)

            subnet.offset_extremes()

            results_by_method[generator].record(size, rep, subnet)

# Output results
print
Exemplo n.º 10
0
def do_experiment(params):
    if params['dump_fits'] and params['load_fits']:
        print 'Warning: simultaneously dumping and loading is a bad idea.'
        
    if params['dump_fits']:
        fits = []

    if params['load_fits']:
        with open(params['load_fits'], 'r') as fits_file:
            loaded_params_pick, loaded_fits = json.load(fits_file)

        loaded_params = dict([(k,unpick(v)) for (k,v) in loaded_params_pick])

        # Compare on parameters that control data generation and inference
        run_params = ['N', 'B', 'theta_sd', 'theta_fixed',
                      'alpha_unif_sd', 'alpha_norm_sd', 'alpha_gamma_sd',
                      'cov_unif_sd', 'cov_norm_sd', 'cov_disc_sd',
                      'kappa_target', 'pre_offset', 'post_fit',
                      'fit_nonstationary', 'fit_method', 'num_reps',
                      'is_T', 'sampling', 'sub_sizes_r', 'sub_sizes_c',
                      'random_seed']

        for p in run_params:
            if not np.all(loaded_params[p] == params[p]):
                print 'Warning: load mismatch on', p
    
    # Set random seed for reproducible output
    seed = Seed(params['random_seed'])

    # Initialize full network
    arr = Network(params['N'])

    # Generate node-level propensities to extend and receive edges
    if params['alpha_norm_sd'] > 0.0:
        alpha_norm(arr, params['alpha_norm_sd'])
    elif params['alpha_unif_sd'] > 0.0:
        alpha_unif(arr, params['alpha_unif_sd'])
    elif params['alpha_gamma_sd'] > 0.0:
        # Choosing location somewhat arbitrarily to give unit skewness
        alpha_gamma(arr, 4.0, params['alpha_gamma_sd'])
    else:
        alpha_zero(arr)

    # Generate covariates and associated coefficients
    data_model = NonstationaryLogistic()
    covariates = []
    for b in range(params['B']):
        name = 'x_%d' % b
        covariates.append(name)

        if name in params['theta_fixed']:
            data_model.beta[name] = params['theta_fixed'][name]
        else:
            data_model.beta[name] = np.random.normal(0, params['theta_sd'])

        if params['cov_unif_sd'] > 0.0:
            c = np.sqrt(12) / 2
            def f_x(i_1, i_2):
                return np.random.uniform(-c * params['cov_unif_sd'],
                                         c * params['cov_unif_sd'])
        elif params['cov_norm_sd'] > 0.0:
            def f_x(i_1, i_2):
                return np.random.normal(0, params['cov_norm_sd'])
        elif params['cov_disc_sd'] > 0.0:
            def f_x(i_1, i_2):
                return (params['cov_disc_sd'] *
                        (np.sign(np.random.random() - 0.5)))
        else:
            print 'Error: no covariate distribution specified.'
            sys.exit()

        arr.new_edge_covariate(name).from_binary_function_ind(f_x)

    # Generate large network, if necessary
    if not params['sampling'] == 'new':
        data_model.match_kappa(arr, params['kappa_target'])
        arr.generate(data_model)

    if params['fit_nonstationary']:
        fit_model = NonstationaryLogistic()
    else:
        fit_model = StationaryLogistic()
    for c in covariates:
        fit_model.beta[c] = None

    # Set up recording of results from experiment
    results = Results(params['sub_sizes_r'], params['sub_sizes_c'],
                      params['num_reps'], interactive = params['interactive'])
    add_array_stats(results)
    if params['plot_sig']:
        from scipy.stats import chi2
        crit = lambda dof: -0.5 * chi2.ppf(0.95, dof)

        umle_f = lambda n, f: f.nll(n, ignore_offset = True)
        umle_d = lambda n, d: d.nll(n, ignore_offset = True)
        umle_n = lambda n: NonstationaryLogistic().nll(n, ignore_offset = True)
        results.new('UMLE F-N', 'nm',
                    lambda n, d, f: umle_f(n, f) - umle_n(n))
        results.new('UMLE F-D', 'nm',
                    lambda n, d, f: umle_f(n, f) - umle_d(n, d))

        cmle_a_f = lambda n, f: acnll(n.as_dense(), np.exp(f.edge_probabilities(n)))
        cmle_a_d = lambda n, d: acnll(n.as_dense(), np.exp(d.edge_probabilities(n)))
        cmle_a_n = lambda n: acnll(n.as_dense(), np.ones_like(n.as_dense()))
        results.new('CMLE-A F-N', 'nm',
                    lambda n, d, f: cmle_a_f(n, f) - cmle_a_n(n))
        results.new('CMLE-A F-D', 'nm',
                    lambda n, d, f: cmle_a_f(n, f) - cmle_a_d(n, d))

        cmle_is_f = lambda n, f: f.fit_conditional(n, evaluate = True, T = 50)
        cmle_is_d = lambda n, d: d.fit_conditional(n, evaluate = True, T = 50)
        cmle_is_n = lambda n: NonstationaryLogistic().fit_conditional(n, evaluate = True, T = 50)
        results.new('CMLE-IS F-N', 'nm',
                    lambda n, d, f: cmle_is_f(n, f) - cmle_is_n(n))
        results.new('CMLE-IS F-D', 'nm',
                    lambda n, d, f: cmle_is_f(n, f) - cmle_is_d(n, d))

        c_cmle_f = lambda n, f: f.fit_c_conditional(n, evaluate = True)
        c_cmle_d = lambda n, d: d.fit_c_conditional(n, evaluate = True)
        c_cmle_n = lambda n: NonstationaryLogistic().fit_c_conditional(n, evaluate = True)
        results.new('C-CMLE F-N', 'nm',
                    lambda n, d, f: c_cmle_f(n, f) - c_cmle_n(n))
        results.new('C-CMLE F-D', 'nm',
                    lambda n, d, f: c_cmle_f(n, f) - c_cmle_d(n, d))

        results.new('UMLE sig.', 'dof',
                    lambda M, N, B: crit((M - 1) + (N - 1) + 1 + B))
        results.new('CMLE sig.', 'dof', lambda M, N, B: crit(B))
        results.new('C-CMLE sig.', 'dof', lambda M, N, B: crit((M - 1) + B))

    if params['sampling'] == 'new':
        results.new('Subnetwork kappa', 'm', lambda d, f: d.kappa)
    def true_est_theta_c(c):
        return (lambda d, f: d.beta[c]), (lambda d, f: f.beta[c])
    for c in covariates:
        # Need to do this hackily to avoid for-loop/lambda-binding weirdness.
        f_true, f_est = true_est_theta_c(c)
        results.new('True theta_{%s}' % c, 'm', f_true)
        results.new('Est. theta_{%s}' % c, 'm', f_est)
    if params['pre_offset'] or params['post_fit']:
        results.new('# Active', 'n',
                    lambda n: np.isfinite(n.offset.matrix()).sum())
    else:
        results.new('# Active', 'n', lambda n: n.M * n.N)
    if params['fisher_information']:
        def info_theta_c(c):
            def f_info_theta_c(d, f):
                return d.I_inv['theta_{%s}' % c]
            return f_info_theta_c
        for c in covariates:
            results.new('Info theta_{%s}' % c, 'm', info_theta_c(c))
    if params['baseline']:
        def rel_mse_p_ij(n, d, f):
            P = d.edge_probabilities(n)
            return rel_mse(f.edge_probabilities(n), f.baseline(n), P)
        results.new('Rel. MSE(P_ij)', 'nm', rel_mse_p_ij)
        if not (params['pre_offset'] or params['post_fit']):
            def rel_mse_logit_p_ij(n, d, f):
                logit_P = d.edge_probabilities(n, logit = True)
                logit_Q = f.baseline_logit(n)
                return rel_mse(f.edge_probabilities(n, logit = True),
                               logit_Q, logit_P)
            results.new('Rel. MSE(logit P_ij)', 'nm', rel_mse_logit_p_ij)

    if params['fit_method'] in ['convex_opt', 'conditional', 'c_conditional',
                                'irls', 'conditional_is']:
        results.new('Wall time (sec.)', 'm',
                    lambda d, f: f.fit_info['wall_time'])
    if params['fit_method'] in ['convex_opt',
                                'conditional', 'conditional_is']:
        def work(f):
            w = 0
            for work_type in ['nll_evals', 'grad_nll_evals', 'cnll_evals']:
                if work_type in f.fit_info:
                    w += f.fit_info[work_type]
            return w
        results.new('Work', 'm', lambda d, f: work(f))
        results.new('||ET_final - T||_2', 'm',
                    lambda d, f: l2(f.fit_info['grad_nll_final']))

    for sub_size in zip(results.M_sizes, results.N_sizes):
        print 'subnetwork size =', sub_size

        if params['sampling'] == 'new':
            gen = RandomSubnetworks(arr, sub_size)
        else:
            gen = RandomSubnetworks(arr, sub_size,
                                    method = params['sampling'])

        for rep in range(params['num_reps']):
            seed.next()
            sub = gen.sample()

            if params['fisher_information']:
                data_model.fisher_information(sub)

            if params['sampling'] == 'new':
                data_model.match_kappa(sub, params['kappa_target'])
                sub.generate(data_model)

            if params['load_fits']:
                fit, loaded_fits = loaded_fits[0], loaded_fits[1:]
                fit_model.beta = unpick(fit['theta'])
                if params['fix_broken_cmle_is']:
                    for b_n in fit_model.beta:
                        fit_model.beta[b_n] += 0.1474
                if 'alpha' in fit:
                    sub.row_covariates['alpha_out'] = unpick(fit['alpha'])
                if 'beta' in fit:
                    sub.col_covariates['alpha_in'] = unpick(fit['beta'])
                if 'kappa' in fit:
                    fit_model.kappa = fit['kappa']
                if 'offset' in fit:
                    sub.offset = unpick(fit['offset'])
                if 'fit_info' in fit:
                    fit_model.fit_info = unpick(fit['fit_info'])
            else:
                if params['pre_offset']:
                    sub.offset_extremes()

                if params['fit_method'] == 'convex_opt':
                    fit_model.fit_convex_opt(sub,
                                             verbose = params['verbose'])
                elif params['fit_method'] == 'irls':
                    fit_model.fit_irls(sub, verbose = params['verbose'])
                elif params['fit_method'] == 'logistic':
                    fit_model.fit_logistic(sub)
                elif params['fit_method'] == 'logistic_l2':
                    fit_model.fit_logistic_l2(sub, prior_precision = 1.0)
                elif params['fit_method'] == 'conditional':
                    fit_model.fit_conditional(sub,
                                              verbose = params['verbose'])
                elif params['fit_method'] == 'conditional_is':
                    fit_model.fit_conditional(sub, T = params['is_T'],
                                              verbose = params['verbose'])
                elif params['fit_method'] == 'c_conditional':
                    fit_model.fit_c_conditional(sub,
                                                verbose = params['verbose'])
                elif params['fit_method'] == 'composite':
                    fit_model.fit_composite(sub, T = 100,
                                            verbose = params['verbose'])
                elif params['fit_method'] == 'brazzale':
                    fit_model.fit_brazzale(sub)
                elif params['fit_method'] == 'saddlepoint':
                    fit_model.fit_saddlepoint(sub)
                elif params['fit_method'] == 'none':
                    pass

                if params['post_fit']:
                    sub.offset_extremes()
                    fit_model.fit_convex_opt(sub, fix_beta = True)

                if params['dump_fits']:
                    fit = {}
                    fit['theta'] = pick(fit_model.beta)
                    if 'alpha_out' in sub.row_covariates:
                        fit['alpha'] = pick(sub.row_covariates['alpha_out'])
                    if 'alpha_in' in sub.row_covariates:
                        fit['beta'] = pick(sub.col_covariates['alpha_in'])
                    if not fit_model.kappa is None:
                        fit['kappa'] = fit_model.kappa
                    if not sub.offset is None:
                        sub.offset.dirty()
                        fit['offset'] = pick(sub.offset)
                    if not fit_model.fit_info is None:
                        fit['fit_info'] = pick(fit_model.fit_info)

                    fits.append(fit)

            if params['find_good'] > 0:
                abs_err = abs(fit_model.beta['x_0'] - data_model.beta['x_0'])
                if abs_err < params['find_good']:
                    print abs_err

                    sub.offset = None
                    fit_model.fit_conditional(sub, T = 1000,
                                              verbose = True)
                    print fit_model.beta['x_0']
                    print fit_model.fit_info

                    f = file('goodmat.mat', 'wb')
                    import scipy.io
                    Y = np.array(sub.as_dense(), dtype=np.float)
                    X = sub.edge_covariates['x_0'].matrix()
                    scipy.io.savemat(f, { 'Y': Y, 'X': X })
                    sys.exit()

            if params['find_bad'] > 0:
                abs_err = abs(fit_model.beta['x_0'] - data_model.beta['x_0'])
                if abs_err > params['find_bad']:
                    print abs_err

                    sub.offset = None
                    fit_model.fit_conditional(sub, T = 1000,
                                              verbose = True)
                    print fit_model.beta['x_0']
                    print fit_model.fit_info

                    f = file('badmat.mat', 'wb')
                    import scipy.io
                    Y = np.array(sub.as_dense(), dtype=np.float)
                    X = sub.edge_covariates['x_0'].matrix()
                    scipy.io.savemat(f, { 'Y': Y, 'X': X })
                    sys.exit()

            results.record(sub_size, rep, sub, data_model, fit_model)

            if params['verbose']:
                print

    if params['dump_fits']:
        with open(params['dump_fits'], 'w') as outfile:
            json.dump(([(p, pick(params[p])) for p in params], fits), outfile)

    # Compute beta MSEs
    covariate_naming = []
    for c in covariates:
        mse_name = 'MSE(theta_{%s})' % c
        true_name = 'True theta_{%s}' % c
        est_name = 'Est. theta_{%s}' % c
        results.estimate_mse(mse_name, true_name, est_name)
        covariate_naming.append((c, mse_name, true_name, est_name))

    # Report parameters for the run
    print 'Parameters:'
    for field in params:
        print '%s: %s' % (field, str(params[field]))

    # Should not vary between runs with the same seed and same number
    # of arrays tested
    seed.final()

    results.summary()

    return results, covariate_naming
Exemplo n.º 11
0
    n_results = results.copy()
    n_results.title = 'Nonstationary fit'
    all_results['n'] = n_results
if params['fit_conditional']:
    c_results = results.copy()
    c_results.title = 'Conditional fit'
    all_results['c'] = c_results
if params['fit_conditional_is']:
    i_results = results.copy()
    i_results.title = 'Conditional (importance sampled) fit'
    all_results['i'] = i_results

for sub_size in params['sub_sizes']:
    print 'subnetwork size = %d' % sub_size

    gen = RandomSubnetworks(net, sub_size, method=params['sampling'])

    for rep in range(params['num_reps']):
        subnet = gen.sample()

        if params['fit_stationary']:
            fit_model.fit_convex_opt(subnet, verbose=True)
            s_results.record(sub_size, rep, subnet, fit_model=fit_model)
            print

        if params['fit_conditional']:
            fit_model.fit_conditional(subnet, verbose=True)
            c_results.record(sub_size, rep, subnet, fit_model=fit_model)
            print

        if params['fit_conditional_is']: