示例#1
0
def ci_cons(X, v, alpha_level, L, theta_l, theta_u,
            K, test = 'lr', corrected = True, verbose = False):
    arr = array_from_data(X, [v])

    fit_model = StationaryLogistic()
    fit_model.beta['x_0'] = None
    fit_model.confidence_cons(arr, 'x_0', alpha_level, K,
                              L, theta_l, theta_u, test, verbose)

    method = 'conservative-%s' % test
    return fit_model.conf['x_0'][method]
def ci_cmle_boot(X, v, alpha_level):
    arr = array_from_data(X, [v])

    A = arr.as_dense()
    r = A.sum(1)
    c = A.sum(0)
    
    s_model = StationaryLogistic()
    s_model.beta['x_0'] = None
    fit_model = FixedMargins(s_model)
    arr.new_row_covariate('r', np.int)[:] = r
    arr.new_col_covariate('c', np.int)[:] = c
    fit_model.fit = fit_model.base_model.fit_conditional

    fit_model.confidence_boot(arr, alpha_level = alpha_level)

    return fit_model.conf['x_0']['pivotal']
示例#3
0
class_probs = np.random.dirichlet(np.repeat(params['class_conc'], params['K']))
z = np.where(np.random.multinomial(1, class_probs, params['N']) == 1)[1]
net.new_node_covariate_int('z_true')[:] = z
data_model = Blockmodel(data_base_model, params['K'], 'z_true')
Theta = np.random.normal(params['Theta_mean'], params['Theta_sd'],
                         (params['K'], params['K']))
Theta += params['Theta_diag'] * np.identity(params['K'])
Theta -= np.mean(Theta)
data_model.Theta = Theta

net.generate(data_model)
if params['plot_network']:
    net.show_heatmap('z_true')

# Initialize fitting model
fit_base_model = StationaryLogistic()
for c in covariates:
    fit_base_model.beta[c] = None
fit_model = Blockmodel(fit_base_model, params['fit_K'])
if params['fit_nonstationary']:
    n_fit_base_model = NonstationaryLogistic()
    for c in covariates:
        n_fit_base_model.beta[c] = None
    n_fit_model = Blockmodel(n_fit_base_model, params['fit_K'])
net.new_node_covariate_int('z')

# Set up recording of results from experiment
s_results = Results(params['sub_sizes'], params['num_reps'], 'Stationary fit')
add_network_stats(s_results)
s_results.new('Subnetwork kappa', 'm', lambda d, f: d.base_model.kappa)
    # contour expects x, y, z generated by meshgrid...
    CS = plt.contour(x, y, np.transpose(z), colors='k')
    plt.plot(theta_star_1, theta_star_2, 'b*', markersize=12)
    plt.plot(theta_opt_1, theta_opt_2, 'ro', markersize=12)
    # plt.clabel(CS, inline = 1, fontsize = 10, fmt = '%1.1f')
    plt.xlabel(r'$\theta_2$', fontsize=14)
    plt.ylabel(r'$\theta_1$', fontsize=14)

    return theta_opt_1, theta_opt_2


# Grid search for stationary and non-stationary fits
plt.subplot(142)
plt.title('Stationary')
grid_fit(StationaryLogistic(), lambda n, m: m.nll(n), profile=True)
plt.subplot(143)
plt.title('Nonstationary')
grid_fit(NonstationaryLogistic(),
         lambda n, m: m.nll(n),
         profile=True,
         pre_offset=True)

# Grid search for conditional fit
plt.subplot(144)
plt.title('Conditional')


def f_nll(n, m):
    P = m.edge_probabilities(n)
    w = P / (1.0 - P)
plt.title('Covariates')
covariate_levels = np.zeros((net.N, net.N))
num_covariates = len(cov_names)
for i, val in enumerate(np.linspace(1.0, 0.4, num_covariates)):
    covariate_levels[net.edge_covariates[cov_names[i]].matrix() == True] = val
heatmap(covariate_levels, 'Blues')
plt.subplot(333)
plt.title('Network')
graph = nx.DiGraph()
for n1, n2 in edges:
    graph.add_edge(n1, n2)
pos = nx.graphviz_layout(graph, prog='neato')
nx.draw(graph, pos, node_size=10, with_labels=False)

print 'Fitting stationary model'
s_model = StationaryLogistic()
for cov_name in cov_names:
    s_model.beta[cov_name] = None
s_model.fit(net, verbose=True)
print 'NLL: %.2f' % s_model.nll(net)
print 'kappa: %.2f' % s_model.kappa
for cov_name in cov_names:
    print '%s: %.2f' % (cov_name, s_model.beta[cov_name])
print

print 'Fitting nonstationary model'
alpha_zero(net)
ns_model = NonstationaryLogistic()
for cov_name in cov_names:
    ns_model.beta[cov_name] = None
ns_model.fit(net, verbose=True)
    def f_x(i_1, i_2):
        return np.random.uniform(-np.sqrt(3), np.sqrt(3))

    arr.new_edge_covariate(name).from_binary_function_ind(f_x)
data_model.match_kappa(arr, params['kappa_target'])

# Specify parameter of interest that  the confidence interval will try
# to capture
for c in params['covariates_of_interest']:
    theta_true = data_model.beta[c]
    print '%s theta_true: %.2f' % (c, theta_true)

# Setup fit model
if params['fit_method'] == 'conditional':
    fit_model = StationaryLogistic()
    for c in covariates:
        fit_model.beta[c] = None
    fit_model.generate = fit_model.generate_margins
    fit_model.fit = fit_model.fit_conditional
else:
    if params['fit_nonstationary']:
        fit_model = NonstationaryLogistic()
    else:
        fit_model = StationaryLogistic()
    for c in covariates:
        fit_model.beta[c] = None

# Test coverage
methods = []
if params['do_wald']:
示例#7
0
plt.title('Covariates')
covariate_levels = np.zeros((net.N, net.N))
num_covariates = len(cov_names)
for i, val in enumerate(np.linspace(1.0, 0.4, num_covariates)):
    covariate_levels[net.edge_covariates[cov_names[i]].matrix() == True] = val
heatmap(covariate_levels, 'Blues')
plt.subplot(333)
plt.title('Network')
graph = nx.DiGraph()
for n1, n2 in edges:
    graph.add_edge(n1, n2)
pos = nx.nx_pydot.graphviz_layout(graph, prog = 'neato')
nx.draw(graph, pos, node_size = 10, with_labels = False)

print 'Fitting stationary model'
s_model = StationaryLogistic()
for cov_name in cov_names:
    s_model.beta[cov_name] = None
s_model.fit(net, verbose = True)
print 'NLL: %.2f' % s_model.nll(net)
print 'kappa: %.2f' % s_model.kappa
for cov_name in cov_names:
    print '%s: %.2f' % (cov_name, s_model.beta[cov_name])
print

print 'Fitting nonstationary model'
alpha_zero(net)
ns_model = NonstationaryLogistic()
for cov_name in cov_names:
    ns_model.beta[cov_name] = None
ns_model.fit(net, verbose = True)
示例#8
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
n_rep = 100
n_boot = 10
alpha_level = 0.05

net = Network(N)
alpha_norm(net, alpha_sd)
for d in range(D):
    net.new_edge_covariate('x_%d' % d)[:,:] = np.random.normal(0, 1, (N, N))

data_model = NonstationaryLogistic()
for d in range(D):
    data_model.beta['x_%d' % d] = np.random.normal(0, 1)
data_model.beta['x_0'] = theta
data_model.match_kappa(net, kappa_target)

s_fit = StationaryLogistic()
ns_fit = NonstationaryLogistic()
for d in range(D):
    s_fit.beta['x_%d' % d] = None
    ns_fit.beta['x_%d' % d] = None

def safe_ci(model, name, method):
    if name in model.conf:
        if method in model.conf[name]:
            return model.conf[name][method]
    else:
        return (0.0, 0.0)

braz_covered = 0
ws_covered = 0
wn_covered = 0
def fit_and_summarize(name, fit_model, use_covs):
    print name
    if use_covs:
        for cov_name in cov_names:
            fit_model.beta[cov_name] = None
    fit_model.fit(net, verbose=params['verbose'])
    print 'NLL: %.2f' % fit_model.nll(net)
    print 'kappa: %.2f' % fit_model.kappa
    if use_covs:
        for cov_name in cov_names:
            print '%s: %.2f' % (cov_name, fit_model.beta[cov_name])
    print '\n'


fit_and_summarize('Stationary', Stationary(), False)
fit_and_summarize('Stationary', StationaryLogistic(), True)
if params['offset_extremes']:
    print 'Detecting subnetworks associated with infinite parameter estimates.\n'
    net.offset_extremes()
    if params['plot']: net.show_offset('pub_date')
fit_and_summarize('Nonstationary', NonstationaryLogistic(), False)
fit_and_summarize('Nonstationary', NonstationaryLogistic(), True)

# Redisplay heatmap, ordered by estimated alphas from last fit, i.e.,
# NonstationaryLogistic with publication date difference covariates
# XX: Following plots are broken
#if params['plot']:
#    net.show_heatmap('alpha_out')
#    net.show_heatmap('alpha_in')

outfile = open('scratch.json', 'w')