+++ /dev/null
-/* pspp - a program for statistical analysis.
- Copyright (C) 2012 Free Software Foundation, Inc.
-
- This program is free software: you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation, either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>. */
-
-
-/*
- References:
- 1. "Coding Logistic Regression with Newton-Raphson", James McCaffrey
- http://msdn.microsoft.com/en-us/magazine/jj618304.aspx
-
- 2. "SPSS Statistical Algorithms" Chapter LOGISTIC REGRESSION Algorithms
-
-
- The Newton Raphson method finds successive approximations to $\bf b$ where
- approximation ${\bf b}_t$ is (hopefully) better than the previous ${\bf b}_{t-1}$.
-
- $ {\bf b}_t = {\bf b}_{t -1} + ({\bf X}^T{\bf W}_{t-1}{\bf X})^{-1}{\bf X}^T({\bf y} - {\bf \pi}_{t-1})$
- where:
-
- $\bf X$ is the $n \times p$ design matrix, $n$ being the number of cases,
- $p$ the number of parameters, \par
- $\bf W$ is the diagonal matrix whose diagonal elements are
- $\hat{\pi}_0(1 - \hat{\pi}_0), \, \hat{\pi}_1(1 - \hat{\pi}_2)\dots \hat{\pi}_{n-1}(1 - \hat{\pi}_{n-1})$
- \par
-
-*/
-
-#include <config.h>
-
-#include <gsl/gsl_blas.h>
-
-#include <gsl/gsl_linalg.h>
-#include <gsl/gsl_cdf.h>
-#include <gsl/gsl_matrix.h>
-#include <gsl/gsl_vector.h>
-#include <math.h>
-
-#include "data/case.h"
-#include "data/casegrouper.h"
-#include "data/casereader.h"
-#include "data/dataset.h"
-#include "data/dictionary.h"
-#include "data/format.h"
-#include "data/value.h"
-#include "language/command.h"
-#include "language/dictionary/split-file.h"
-#include "language/lexer/lexer.h"
-#include "language/lexer/value-parser.h"
-#include "language/lexer/variable-parser.h"
-#include "libpspp/assertion.h"
-#include "libpspp/hash-functions.h"
-#include "libpspp/hmap.h"
-#include "libpspp/ll.h"
-#include "libpspp/message.h"
-#include "libpspp/misc.h"
-#include "math/categoricals.h"
-#include "math/interaction.h"
-#include "output/pivot-table.h"
-
-#include "gettext.h"
-#define N_(msgid) msgid
-#define _(msgid) gettext (msgid)
-
-
-
-
-#define PRINT_EACH_STEP 0x01
-#define PRINT_SUMMARY 0x02
-#define PRINT_CORR 0x04
-#define PRINT_ITER 0x08
-#define PRINT_GOODFIT 0x10
-#define PRINT_CI 0x20
-
-
-#define PRINT_DEFAULT (PRINT_SUMMARY | PRINT_EACH_STEP)
-
-/*
- The constant parameters of the procedure.
- That is, those which are set by the user.
-*/
-struct lr_spec
-{
- /* The dependent variable */
- const struct variable *dep_var;
-
- /* The predictor variables (excluding categorical ones) */
- const struct variable **predictor_vars;
- size_t n_predictor_vars;
-
- /* The categorical predictors */
- struct interaction **cat_predictors;
- size_t n_cat_predictors;
-
-
- /* The union of the categorical and non-categorical variables */
- const struct variable **indep_vars;
- size_t n_indep_vars;
-
-
- /* Which classes of missing vars are to be excluded */
- enum mv_class exclude;
-
- /* The weight variable */
- const struct variable *wv;
-
- /* The dictionary of the dataset */
- const struct dictionary *dict;
-
- /* True iff the constant (intercept) is to be included in the model */
- bool constant;
-
- /* Ths maximum number of iterations */
- int max_iter;
-
- /* Other iteration limiting conditions */
- double bcon;
- double min_epsilon;
- double lcon;
-
- /* The confidence interval (in percent) */
- int confidence;
-
- /* What results should be presented */
- unsigned int print;
-
- /* Inverse logit of the cut point */
- double ilogit_cut_point;
-};
-
-
-/* The results and intermediate result of the procedure.
- These are mutated as the procedure runs. Used for
- temporary variables etc.
-*/
-struct lr_result
-{
- /* Used to indicate if a pass should flag a warning when
- invalid (ie negative or missing) weight values are encountered */
- bool warn_bad_weight;
-
- /* The two values of the dependent variable. */
- union value y0;
- union value y1;
-
-
- /* The sum of caseweights */
- double cc;
-
- /* The number of missing and nonmissing cases */
- casenumber n_missing;
- casenumber n_nonmissing;
-
-
- gsl_matrix *hessian;
-
- /* The categoricals and their payload. Null if the analysis has no
- categorical predictors */
- struct categoricals *cats;
- struct payload cp;
-
-
- /* The estimates of the predictor coefficients */
- gsl_vector *beta_hat;
-
- /* The predicted classifications:
- True Negative, True Positive, False Negative, False Positive */
- double tn, tp, fn, fp;
-};
-
-
-/*
- Convert INPUT into a dichotomous scalar, according to how the dependent variable's
- values are mapped.
- For simple cases, this is a 1:1 mapping
- The return value is always either 0 or 1
-*/
-static double
-map_dependent_var (const struct lr_spec *cmd, const struct lr_result *res, const union value *input)
-{
- const int width = var_get_width (cmd->dep_var);
- if (value_equal (input, &res->y0, width))
- return 0;
-
- if (value_equal (input, &res->y1, width))
- return 1;
-
- /* This should never happen. If it does, then y0 and/or y1 have probably not been set */
- NOT_REACHED ();
-
- return SYSMIS;
-}
-
-static void output_classification_table (const struct lr_spec *cmd, const struct lr_result *res);
-
-static void output_categories (const struct lr_spec *cmd, const struct lr_result *res);
-
-static void output_depvarmap (const struct lr_spec *cmd, const struct lr_result *);
-
-static void output_variables (const struct lr_spec *cmd,
- const struct lr_result *);
-
-static void output_model_summary (const struct lr_result *,
- double initial_likelihood, double likelihood);
-
-static void case_processing_summary (const struct lr_result *);
-
-
-/* Return the value of case C corresponding to the INDEX'th entry in the
- model */
-static double
-predictor_value (const struct ccase *c,
- const struct variable **x, size_t n_x,
- const struct categoricals *cats,
- size_t index)
-{
- /* Values of the scalar predictor variables */
- if (index < n_x)
- return case_num (c, x[index]);
-
- /* Coded values of categorical predictor variables (or interactions) */
- if (cats && index - n_x < categoricals_df_total (cats))
- {
- double x = categoricals_get_dummy_code_for_case (cats, index - n_x, c);
- return x;
- }
-
- /* The constant term */
- return 1.0;
-}
-
-
-/*
- Return the probability beta_hat (that is the estimator logit(y))
- corresponding to the coefficient estimator for case C
-*/
-static double
-pi_hat (const struct lr_spec *cmd,
- const struct lr_result *res,
- const struct variable **x, size_t n_x,
- const struct ccase *c)
-{
- int v0;
- double pi = 0;
- size_t n_coeffs = res->beta_hat->size;
-
- if (cmd->constant)
- {
- pi += gsl_vector_get (res->beta_hat, res->beta_hat->size - 1);
- n_coeffs--;
- }
-
- for (v0 = 0; v0 < n_coeffs; ++v0)
- {
- pi += gsl_vector_get (res->beta_hat, v0) *
- predictor_value (c, x, n_x, res->cats, v0);
- }
-
- pi = 1.0 / (1.0 + exp(-pi));
-
- return pi;
-}
-
-
-/*
- Calculates the Hessian matrix X' V X,
- where: X is the n by N_X matrix comprising the n cases in INPUT
- V is a diagonal matrix { (pi_hat_0)(1 - pi_hat_0), (pi_hat_1)(1 - pi_hat_1), ... (pi_hat_{N-1})(1 - pi_hat_{N-1})}
- (the partial derivative of the predicted values)
-
- If ALL predicted values derivatives are close to zero or one, then CONVERGED
- will be set to true.
-*/
-static void
-hessian (const struct lr_spec *cmd,
- struct lr_result *res,
- struct casereader *input,
- const struct variable **x, size_t n_x,
- bool *converged)
-{
- struct casereader *reader;
- struct ccase *c;
-
- double max_w = -DBL_MAX;
-
- gsl_matrix_set_zero (res->hessian);
-
- for (reader = casereader_clone (input);
- (c = casereader_read (reader)) != NULL; case_unref (c))
- {
- int v0, v1;
- double pi = pi_hat (cmd, res, x, n_x, c);
-
- double weight = dict_get_case_weight (cmd->dict, c, &res->warn_bad_weight);
- double w = pi * (1 - pi);
- if (w > max_w)
- max_w = w;
- w *= weight;
-
- for (v0 = 0; v0 < res->beta_hat->size; ++v0)
- {
- double in0 = predictor_value (c, x, n_x, res->cats, v0);
- for (v1 = 0; v1 < res->beta_hat->size; ++v1)
- {
- double in1 = predictor_value (c, x, n_x, res->cats, v1);
- double *o = gsl_matrix_ptr (res->hessian, v0, v1);
- *o += in0 * w * in1;
- }
- }
- }
- casereader_destroy (reader);
-
- if (max_w < cmd->min_epsilon)
- {
- *converged = true;
- msg (MN, _("All predicted values are either 1 or 0"));
- }
-}
-
-
-/* Calculates the value X' (y - pi)
- where X is the design model,
- y is the vector of observed independent variables
- pi is the vector of estimates for y
-
- Side effects:
- the likelihood is stored in LIKELIHOOD;
- the predicted values are placed in the respective tn, fn, tp fp values in RES
-*/
-static gsl_vector *
-xt_times_y_pi (const struct lr_spec *cmd,
- struct lr_result *res,
- struct casereader *input,
- const struct variable **x, size_t n_x,
- const struct variable *y_var,
- double *llikelihood)
-{
- struct casereader *reader;
- struct ccase *c;
- gsl_vector *output = gsl_vector_calloc (res->beta_hat->size);
-
- *llikelihood = 0.0;
- res->tn = res->tp = res->fn = res->fp = 0;
- for (reader = casereader_clone (input);
- (c = casereader_read (reader)) != NULL; case_unref (c))
- {
- double pred_y = 0;
- int v0;
- double pi = pi_hat (cmd, res, x, n_x, c);
- double weight = dict_get_case_weight (cmd->dict, c, &res->warn_bad_weight);
-
-
- double y = map_dependent_var (cmd, res, case_data (c, y_var));
-
- *llikelihood += (weight * y) * log (pi) + log (1 - pi) * weight * (1 - y);
-
- for (v0 = 0; v0 < res->beta_hat->size; ++v0)
- {
- double in0 = predictor_value (c, x, n_x, res->cats, v0);
- double *o = gsl_vector_ptr (output, v0);
- *o += in0 * (y - pi) * weight;
- pred_y += gsl_vector_get (res->beta_hat, v0) * in0;
- }
-
- /* Count the number of cases which would be correctly/incorrectly classified by this
- estimated model */
- if (pred_y <= cmd->ilogit_cut_point)
- {
- if (y == 0)
- res->tn += weight;
- else
- res->fn += weight;
- }
- else
- {
- if (y == 0)
- res->fp += weight;
- else
- res->tp += weight;
- }
- }
-
- casereader_destroy (reader);
-
- return output;
-}
-
-\f
-
-/* "payload" functions for the categoricals.
- The only function is to accumulate the frequency of each
- category.
- */
-
-static void *
-frq_create (const void *aux1 UNUSED, void *aux2 UNUSED)
-{
- return xzalloc (sizeof (double));
-}
-
-static void
-frq_update (const void *aux1 UNUSED, void *aux2 UNUSED,
- void *ud, const struct ccase *c UNUSED , double weight)
-{
- double *freq = ud;
- *freq += weight;
-}
-
-static void
-frq_destroy (const void *aux1 UNUSED, void *aux2 UNUSED, void *user_data)
-{
- free (user_data);
-}
-
-\f
-
-/*
- Makes an initial pass though the data, doing the following:
-
- * Checks that the dependent variable is dichotomous,
- * Creates and initialises the categoricals,
- * Accumulates summary results,
- * Calculates necessary initial values.
- * Creates an initial value for \hat\beta the vector of beta_hats of \beta
-
- Returns true if successful
-*/
-static bool
-initial_pass (const struct lr_spec *cmd, struct lr_result *res, struct casereader *input)
-{
- const int width = var_get_width (cmd->dep_var);
-
- struct ccase *c;
- struct casereader *reader;
-
- double sum;
- double sumA = 0.0;
- double sumB = 0.0;
-
- bool v0set = false;
- bool v1set = false;
-
- size_t n_coefficients = cmd->n_predictor_vars;
- if (cmd->constant)
- n_coefficients++;
-
- /* Create categoricals if appropriate */
- if (cmd->n_cat_predictors > 0)
- {
- res->cp.create = frq_create;
- res->cp.update = frq_update;
- res->cp.calculate = NULL;
- res->cp.destroy = frq_destroy;
-
- res->cats = categoricals_create (cmd->cat_predictors, cmd->n_cat_predictors,
- cmd->wv, MV_ANY);
-
- categoricals_set_payload (res->cats, &res->cp, cmd, res);
- }
-
- res->cc = 0;
- for (reader = casereader_clone (input);
- (c = casereader_read (reader)) != NULL; case_unref (c))
- {
- int v;
- bool missing = false;
- double weight = dict_get_case_weight (cmd->dict, c, &res->warn_bad_weight);
- const union value *depval = case_data (c, cmd->dep_var);
-
- if (var_is_value_missing (cmd->dep_var, depval) & cmd->exclude)
- {
- missing = true;
- }
- else
- for (v = 0; v < cmd->n_indep_vars; ++v)
- {
- const union value *val = case_data (c, cmd->indep_vars[v]);
- if (var_is_value_missing (cmd->indep_vars[v], val) & cmd->exclude)
- {
- missing = true;
- break;
- }
- }
-
- /* Accumulate the missing and non-missing counts */
- if (missing)
- {
- res->n_missing++;
- continue;
- }
- res->n_nonmissing++;
-
- /* Find the values of the dependent variable */
- if (!v0set)
- {
- value_clone (&res->y0, depval, width);
- v0set = true;
- }
- else if (!v1set)
- {
- if (!value_equal (&res->y0, depval, width))
- {
- value_clone (&res->y1, depval, width);
- v1set = true;
- }
- }
- else
- {
- if (!value_equal (&res->y0, depval, width)
- &&
- !value_equal (&res->y1, depval, width)
- )
- {
- msg (ME, _("Dependent variable's values are not dichotomous."));
- case_unref (c);
- goto error;
- }
- }
-
- if (v0set && value_equal (&res->y0, depval, width))
- sumA += weight;
-
- if (v1set && value_equal (&res->y1, depval, width))
- sumB += weight;
-
-
- res->cc += weight;
-
- categoricals_update (res->cats, c);
- }
- casereader_destroy (reader);
-
- categoricals_done (res->cats);
-
- sum = sumB;
-
- /* Ensure that Y0 is less than Y1. Otherwise the mapping gets
- inverted, which is confusing to users */
- if (var_is_numeric (cmd->dep_var) && value_compare_3way (&res->y0, &res->y1, width) > 0)
- {
- union value tmp;
- value_clone (&tmp, &res->y0, width);
- value_copy (&res->y0, &res->y1, width);
- value_copy (&res->y1, &tmp, width);
- value_destroy (&tmp, width);
- sum = sumA;
- }
-
- n_coefficients += categoricals_df_total (res->cats);
- res->beta_hat = gsl_vector_calloc (n_coefficients);
-
- if (cmd->constant)
- {
- double mean = sum / res->cc;
- gsl_vector_set (res->beta_hat, res->beta_hat->size - 1, log (mean / (1 - mean)));
- }
-
- return true;
-
- error:
- casereader_destroy (reader);
- return false;
-}
-
-
-
-/* Start of the logistic regression routine proper */
-static bool
-run_lr (const struct lr_spec *cmd, struct casereader *input,
- const struct dataset *ds UNUSED)
-{
- int i;
-
- bool converged = false;
-
- /* Set the log likelihoods to a sentinel value */
- double log_likelihood = SYSMIS;
- double prev_log_likelihood = SYSMIS;
- double initial_log_likelihood = SYSMIS;
-
- struct lr_result work;
- work.n_missing = 0;
- work.n_nonmissing = 0;
- work.warn_bad_weight = true;
- work.cats = NULL;
- work.beta_hat = NULL;
- work.hessian = NULL;
-
- /* Get the initial estimates of \beta and their standard errors.
- And perform other auxiliary initialisation. */
- if (!initial_pass (cmd, &work, input))
- goto error;
-
- for (i = 0; i < cmd->n_cat_predictors; ++i)
- {
- if (1 >= categoricals_n_count (work.cats, i))
- {
- struct string str;
- ds_init_empty (&str);
-
- interaction_to_string (cmd->cat_predictors[i], &str);
-
- msg (ME, _("Category %s does not have at least two distinct values. Logistic regression will not be run."),
- ds_cstr(&str));
- ds_destroy (&str);
- goto error;
- }
- }
-
- output_depvarmap (cmd, &work);
-
- case_processing_summary (&work);
-
-
- input = casereader_create_filter_missing (input,
- cmd->indep_vars,
- cmd->n_indep_vars,
- cmd->exclude,
- NULL,
- NULL);
-
- input = casereader_create_filter_missing (input,
- &cmd->dep_var,
- 1,
- cmd->exclude,
- NULL,
- NULL);
-
- work.hessian = gsl_matrix_calloc (work.beta_hat->size, work.beta_hat->size);
-
- /* Start the Newton Raphson iteration process... */
- for(i = 0; i < cmd->max_iter; ++i)
- {
- double min, max;
- gsl_vector *v;
-
-
- hessian (cmd, &work, input,
- cmd->predictor_vars, cmd->n_predictor_vars,
- &converged);
-
- gsl_linalg_cholesky_decomp (work.hessian);
- gsl_linalg_cholesky_invert (work.hessian);
-
- v = xt_times_y_pi (cmd, &work, input,
- cmd->predictor_vars, cmd->n_predictor_vars,
- cmd->dep_var,
- &log_likelihood);
-
- {
- /* delta = M.v */
- gsl_vector *delta = gsl_vector_alloc (v->size);
- gsl_blas_dgemv (CblasNoTrans, 1.0, work.hessian, v, 0, delta);
- gsl_vector_free (v);
-
-
- gsl_vector_add (work.beta_hat, delta);
-
- gsl_vector_minmax (delta, &min, &max);
-
- if (fabs (min) < cmd->bcon && fabs (max) < cmd->bcon)
- {
- msg (MN, _("Estimation terminated at iteration number %d because parameter estimates changed by less than %g"),
- i + 1, cmd->bcon);
- converged = true;
- }
-
- gsl_vector_free (delta);
- }
-
- if (i > 0)
- {
- if (-log_likelihood > -(1.0 - cmd->lcon) * prev_log_likelihood)
- {
- msg (MN, _("Estimation terminated at iteration number %d because Log Likelihood decreased by less than %g%%"), i + 1, 100 * cmd->lcon);
- converged = true;
- }
- }
- if (i == 0)
- initial_log_likelihood = log_likelihood;
- prev_log_likelihood = log_likelihood;
-
- if (converged)
- break;
- }
-
-
-
- if (!converged)
- msg (MW, _("Estimation terminated at iteration number %d because maximum iterations has been reached"), i);
-
-
- output_model_summary (&work, initial_log_likelihood, log_likelihood);
-
- if (work.cats)
- output_categories (cmd, &work);
-
- output_classification_table (cmd, &work);
- output_variables (cmd, &work);
-
- casereader_destroy (input);
- gsl_matrix_free (work.hessian);
- gsl_vector_free (work.beta_hat);
- categoricals_destroy (work.cats);
-
- return true;
-
- error:
- casereader_destroy (input);
- gsl_matrix_free (work.hessian);
- gsl_vector_free (work.beta_hat);
- categoricals_destroy (work.cats);
-
- return false;
-}
-
-struct variable_node
-{
- struct hmap_node node; /* Node in hash map. */
- const struct variable *var; /* The variable */
-};
-
-static struct variable_node *
-lookup_variable (const struct hmap *map, const struct variable *var, unsigned int hash)
-{
- struct variable_node *vn;
- HMAP_FOR_EACH_WITH_HASH (vn, struct variable_node, node, hash, map)
- if (vn->var == var)
- return vn;
-
- return NULL;
-}
-
-static void
-insert_variable (struct hmap *map, const struct variable *var, unsigned int hash)
-{
- if (!lookup_variable (map, var, hash))
- {
- struct variable_node *vn = xmalloc (sizeof *vn);
- *vn = (struct variable_node) { .var = var };
- hmap_insert (map, &vn->node, hash);
- }
-}
-
-/* Parse the LOGISTIC REGRESSION command syntax */
-int
-cmd_logistic (struct lexer *lexer, struct dataset *ds)
-{
- /* Temporary location for the predictor variables.
- These may or may not include the categorical predictors */
- const struct variable **pred_vars = NULL;
- size_t n_pred_vars = 0;
- double cp = 0.5;
-
- struct dictionary *dict = dataset_dict (ds);
- struct lr_spec lr = {
- .dict = dict,
- .exclude = MV_ANY,
- .wv = dict_get_weight (dict),
- .max_iter = 20,
- .lcon = 0.0000,
- .bcon = 0.001,
- .min_epsilon = 0.00000001,
- .constant = true,
- .confidence = 95,
- .print = PRINT_DEFAULT,
- };
-
- if (lex_match_id (lexer, "VARIABLES"))
- lex_match (lexer, T_EQUALS);
-
- lr.dep_var = parse_variable_const (lexer, lr.dict);
- if (!lr.dep_var)
- goto error;
-
- if (!lex_force_match (lexer, T_WITH))
- goto error;
-
- if (!parse_variables_const (lexer, lr.dict, &pred_vars, &n_pred_vars,
- PV_NO_DUPLICATE))
- goto error;
-
- while (lex_token (lexer) != T_ENDCMD)
- {
- lex_match (lexer, T_SLASH);
-
- if (lex_match_id (lexer, "MISSING"))
- {
- lex_match (lexer, T_EQUALS);
- while (lex_token (lexer) != T_ENDCMD
- && lex_token (lexer) != T_SLASH)
- {
- if (lex_match_id (lexer, "INCLUDE"))
- lr.exclude = MV_SYSTEM;
- else if (lex_match_id (lexer, "EXCLUDE"))
- lr.exclude = MV_ANY;
- else
- {
- lex_error_expecting (lexer, "INCLUDE", "EXCLUDE");
- goto error;
- }
- }
- }
- else if (lex_match_id (lexer, "ORIGIN"))
- lr.constant = false;
- else if (lex_match_id (lexer, "NOORIGIN"))
- lr.constant = true;
- else if (lex_match_id (lexer, "NOCONST"))
- lr.constant = false;
- else if (lex_match_id (lexer, "EXTERNAL"))
- {
- /* This is for compatibility. It does nothing */
- }
- else if (lex_match_id (lexer, "CATEGORICAL"))
- {
- lex_match (lexer, T_EQUALS);
- struct variable **cats;
- size_t n_cats;
- if (!parse_variables (lexer, lr.dict, &cats, &n_cats, PV_NO_DUPLICATE))
- goto error;
-
- lr.cat_predictors = xrealloc (lr.cat_predictors,
- sizeof *lr.cat_predictors
- * (n_cats + lr.n_cat_predictors));
- for (size_t i = 0; i < n_cats; i++)
- lr.cat_predictors[lr.n_cat_predictors++] = interaction_create (cats[i]);
- free (cats);
- }
- else if (lex_match_id (lexer, "PRINT"))
- {
- lex_match (lexer, T_EQUALS);
- while (lex_token (lexer) != T_ENDCMD && lex_token (lexer) != T_SLASH)
- {
- if (lex_match_id (lexer, "DEFAULT"))
- lr.print |= PRINT_DEFAULT;
- else if (lex_match_id (lexer, "SUMMARY"))
- lr.print |= PRINT_SUMMARY;
-#if 0
- else if (lex_match_id (lexer, "CORR"))
- lr.print |= PRINT_CORR;
- else if (lex_match_id (lexer, "ITER"))
- lr.print |= PRINT_ITER;
- else if (lex_match_id (lexer, "GOODFIT"))
- lr.print |= PRINT_GOODFIT;
-#endif
- else if (lex_match_id (lexer, "CI"))
- {
- lr.print |= PRINT_CI;
- if (!lex_force_match (lexer, T_LPAREN)
- || !lex_force_num (lexer))
- goto error;
- lr.confidence = lex_number (lexer);
- lex_get (lexer);
- if (!lex_force_match (lexer, T_RPAREN))
- goto error;
- }
- else if (lex_match_id (lexer, "ALL"))
- lr.print = ~0x0000;
- else
- {
- lex_error_expecting (lexer, "DEFAULT", "SUMMARY",
-#if 0
- "CORR", "ITER", "GOODFIT",
-#endif
- "CI", "ALL");
- goto error;
- }
- }
- }
- else if (lex_match_id (lexer, "CRITERIA"))
- {
- lex_match (lexer, T_EQUALS);
- while (lex_token (lexer) != T_ENDCMD && lex_token (lexer) != T_SLASH)
- {
- if (lex_match_id (lexer, "BCON"))
- {
- if (!lex_force_match (lexer, T_LPAREN)
- || !lex_force_num (lexer))
- goto error;
- lr.bcon = lex_number (lexer);
- lex_get (lexer);
- if (!lex_force_match (lexer, T_RPAREN))
- goto error;
- }
- else if (lex_match_id (lexer, "ITERATE"))
- {
- if (!lex_force_match (lexer, T_LPAREN)
- || !lex_force_int_range (lexer, "ITERATE", 0, INT_MAX))
- goto error;
- lr.max_iter = lex_integer (lexer);
- lex_get (lexer);
- if (!lex_force_match (lexer, T_RPAREN))
- goto error;
- }
- else if (lex_match_id (lexer, "LCON"))
- {
- if (!lex_force_match (lexer, T_LPAREN)
- || !lex_force_num (lexer))
- goto error;
- lr.lcon = lex_number (lexer);
- lex_get (lexer);
- if (!lex_force_match (lexer, T_RPAREN))
- goto error;
- }
- else if (lex_match_id (lexer, "EPS"))
- {
- if (!lex_force_match (lexer, T_LPAREN)
- || !lex_force_num (lexer))
- goto error;
- lr.min_epsilon = lex_number (lexer);
- lex_get (lexer);
- if (!lex_force_match (lexer, T_RPAREN))
- goto error;
- }
- else if (lex_match_id (lexer, "CUT"))
- {
- if (!lex_force_match (lexer, T_LPAREN)
- || !lex_force_num_range_closed (lexer, "CUT", 0, 1))
- goto error;
-
- cp = lex_number (lexer);
-
- lex_get (lexer);
- if (!lex_force_match (lexer, T_RPAREN))
- goto error;
- }
- else
- {
- lex_error_expecting (lexer, "BCON", "ITERATE", "LCON", "EPS",
- "CUT");
- goto error;
- }
- }
- }
- else
- {
- lex_error_expecting (lexer, "MISSING", "ORIGIN", "NOORIGIN",
- "NOCONST", "EXTERNAL", "CATEGORICAL",
- "PRINT", "CRITERIA");
- goto error;
- }
- }
-
- lr.ilogit_cut_point = - log (1/cp - 1);
-
- /* Copy the predictor variables from the temporary location into the
- final one, dropping any categorical variables which appear there.
- FIXME: This is O(NxM).
- */
- struct hmap allvars = HMAP_INITIALIZER (allvars);
- size_t allocated_predictor_vars = 0;
- for (size_t v = 0; v < n_pred_vars; ++v)
- {
- bool drop = false;
- const struct variable *var = pred_vars[v];
-
- unsigned int hash = hash_pointer (var, 0);
- insert_variable (&allvars, var, hash);
-
- for (size_t cv = 0; cv < lr.n_cat_predictors; ++cv)
- {
- const struct interaction *iact = lr.cat_predictors[cv];
- for (size_t iv = 0; iv < iact->n_vars; ++iv)
- {
- const struct variable *ivar = iact->vars[iv];
- unsigned int hash = hash_pointer (ivar, 0);
- insert_variable (&allvars, ivar, hash);
-
- if (var == ivar)
- drop = true;
- }
- }
-
- if (drop)
- continue;
-
- if (lr.n_predictor_vars >= allocated_predictor_vars)
- lr.predictor_vars = x2nrealloc (lr.predictor_vars,
- &allocated_predictor_vars,
- sizeof *lr.predictor_vars);
- lr.predictor_vars[lr.n_predictor_vars++] = var;
- }
-
- lr.n_indep_vars = hmap_count (&allvars);
- lr.indep_vars = xmalloc (lr.n_indep_vars * sizeof *lr.indep_vars);
-
- /* Interate over each variable and push it into the array */
- size_t x = 0;
- struct variable_node *vn, *next;
- HMAP_FOR_EACH_SAFE (vn, next, struct variable_node, node, &allvars)
- {
- lr.indep_vars[x++] = vn->var;
- hmap_delete (&allvars, &vn->node);
- free (vn);
- }
- assert (x == lr.n_indep_vars);
- hmap_destroy (&allvars);
-
- /* Run logistical regression for each split group. */
- struct casegrouper *grouper = casegrouper_create_splits (proc_open (ds), lr.dict);
- struct casereader *group;
- bool ok = true;
- while (casegrouper_get_next_group (grouper, &group))
- ok = run_lr (&lr, group, ds) && ok;
- ok = casegrouper_destroy (grouper) && ok;
- ok = proc_commit (ds) && ok;
-
- for (size_t i = 0; i < lr.n_cat_predictors; ++i)
- interaction_destroy (lr.cat_predictors[i]);
- free (lr.predictor_vars);
- free (lr.cat_predictors);
- free (lr.indep_vars);
- free (pred_vars);
-
- return CMD_SUCCESS;
-
- error:
- for (size_t i = 0; i < lr.n_cat_predictors; ++i)
- interaction_destroy (lr.cat_predictors[i]);
- free (lr.predictor_vars);
- free (lr.cat_predictors);
- free (lr.indep_vars);
- free (pred_vars);
-
- return CMD_FAILURE;
-}
-
-
-\f
-
-/* Show the Dependent Variable Encoding box.
- This indicates how the dependent variable
- is mapped to the internal zero/one values.
-*/
-static void
-output_depvarmap (const struct lr_spec *cmd, const struct lr_result *res)
-{
- struct pivot_table *table = pivot_table_create (
- N_("Dependent Variable Encoding"));
-
- pivot_dimension_create (table, PIVOT_AXIS_COLUMN, N_("Mapping"),
- N_("Internal Value"));
-
- struct pivot_dimension *original = pivot_dimension_create (
- table, PIVOT_AXIS_ROW, N_("Original Value"));
- original->root->show_label = true;
-
- for (int i = 0; i < 2; i++)
- {
- const union value *v = i ? &res->y1 : &res->y0;
- int orig_idx = pivot_category_create_leaf (
- original->root, pivot_value_new_var_value (cmd->dep_var, v));
- pivot_table_put2 (table, 0, orig_idx, pivot_value_new_number (
- map_dependent_var (cmd, res, v)));
- }
-
- pivot_table_submit (table);
-}
-
-
-/* Show the Variables in the Equation box */
-static void
-output_variables (const struct lr_spec *cmd,
- const struct lr_result *res)
-{
- struct pivot_table *table = pivot_table_create (
- N_("Variables in the Equation"));
-
- struct pivot_dimension *statistics = pivot_dimension_create (
- table, PIVOT_AXIS_COLUMN, N_("Statistics"),
- N_("B"), PIVOT_RC_OTHER,
- N_("S.E."), PIVOT_RC_OTHER,
- N_("Wald"), PIVOT_RC_OTHER,
- N_("df"), PIVOT_RC_INTEGER,
- N_("Sig."), PIVOT_RC_SIGNIFICANCE,
- N_("Exp(B)"), PIVOT_RC_OTHER);
- if (cmd->print & PRINT_CI)
- {
- struct pivot_category *group = pivot_category_create_group__ (
- statistics->root,
- pivot_value_new_text_format (N_("%d%% CI for Exp(B)"),
- cmd->confidence));
- pivot_category_create_leaves (group, N_("Lower"), N_("Upper"));
- }
-
- struct pivot_dimension *variables = pivot_dimension_create (
- table, PIVOT_AXIS_ROW, N_("Variables"));
- struct pivot_category *step1 = pivot_category_create_group (
- variables->root, N_("Step 1"));
-
- int ivar = 0;
- int idx_correction = 0;
- int i = 0;
-
- int nr = cmd->n_predictor_vars;
- if (cmd->constant)
- nr++;
- if (res->cats)
- nr += categoricals_df_total (res->cats) + cmd->n_cat_predictors;
-
- for (int row = 0; row < nr; row++)
- {
- const int idx = row - idx_correction;
-
- int var_idx;
- if (idx < cmd->n_predictor_vars)
- var_idx = pivot_category_create_leaf (
- step1, pivot_value_new_variable (cmd->predictor_vars[idx]));
- else if (i < cmd->n_cat_predictors)
- {
- const struct interaction *cat_predictors = cmd->cat_predictors[i];
- struct string str = DS_EMPTY_INITIALIZER;
- interaction_to_string (cat_predictors, &str);
- if (ivar != 0)
- ds_put_format (&str, "(%d)", ivar);
- var_idx = pivot_category_create_leaf (
- step1, pivot_value_new_user_text_nocopy (ds_steal_cstr (&str)));
-
- int df = categoricals_df (res->cats, i);
- bool summary = ivar == 0;
- if (summary)
- {
- /* Calculate the Wald statistic,
- which is \beta' C^-1 \beta .
- where \beta is the vector of the coefficient estimates comprising this
- categorial variable. and C is the corresponding submatrix of the
- hessian matrix.
- */
- gsl_matrix_const_view mv =
- gsl_matrix_const_submatrix (res->hessian, idx, idx, df, df);
- gsl_matrix *subhessian = gsl_matrix_alloc (mv.matrix.size1, mv.matrix.size2);
- gsl_vector_const_view vv = gsl_vector_const_subvector (res->beta_hat, idx, df);
- gsl_vector *temp = gsl_vector_alloc (df);
-
- gsl_matrix_memcpy (subhessian, &mv.matrix);
- gsl_linalg_cholesky_decomp (subhessian);
- gsl_linalg_cholesky_invert (subhessian);
-
- gsl_blas_dgemv (CblasTrans, 1.0, subhessian, &vv.vector, 0, temp);
- double wald;
- gsl_blas_ddot (temp, &vv.vector, &wald);
-
- double entries[] = { wald, df, gsl_cdf_chisq_Q (wald, df) };
- for (size_t j = 0; j < sizeof entries / sizeof *entries; j++)
- pivot_table_put2 (table, j + 2, var_idx,
- pivot_value_new_number (entries[j]));
-
- idx_correction++;
- gsl_matrix_free (subhessian);
- gsl_vector_free (temp);
- }
-
- if (ivar++ == df)
- {
- ++i; /* next interaction */
- ivar = 0;
- }
-
- if (summary)
- continue;
- }
- else
- var_idx = pivot_category_create_leaves (step1, N_("Constant"));
-
- double b = gsl_vector_get (res->beta_hat, idx);
- double sigma2 = gsl_matrix_get (res->hessian, idx, idx);
- double wald = pow2 (b) / sigma2;
- double df = 1;
- double wc = (gsl_cdf_ugaussian_Pinv (0.5 + cmd->confidence / 200.0)
- * sqrt (sigma2));
- bool show_ci = cmd->print & PRINT_CI && row < nr - cmd->constant;
-
- double entries[] = {
- b,
- sqrt (sigma2),
- wald,
- df,
- gsl_cdf_chisq_Q (wald, df),
- exp (b),
- show_ci ? exp (b - wc) : SYSMIS,
- show_ci ? exp (b + wc) : SYSMIS,
- };
- for (size_t j = 0; j < sizeof entries / sizeof *entries; j++)
- if (entries[j] != SYSMIS)
- pivot_table_put2 (table, j, var_idx,
- pivot_value_new_number (entries[j]));
- }
-
- pivot_table_submit (table);
-}
-
-
-/* Show the model summary box */
-static void
-output_model_summary (const struct lr_result *res,
- double initial_log_likelihood, double log_likelihood)
-{
- struct pivot_table *table = pivot_table_create (N_("Model Summary"));
-
- pivot_dimension_create (table, PIVOT_AXIS_COLUMN, N_("Statistics"),
- N_("-2 Log likelihood"), PIVOT_RC_OTHER,
- N_("Cox & Snell R Square"), PIVOT_RC_OTHER,
- N_("Nagelkerke R Square"), PIVOT_RC_OTHER);
-
- struct pivot_dimension *step = pivot_dimension_create (
- table, PIVOT_AXIS_ROW, N_("Step"));
- step->root->show_label = true;
- pivot_category_create_leaf (step->root, pivot_value_new_integer (1));
-
- double cox = (1.0 - exp ((initial_log_likelihood - log_likelihood)
- * (2 / res->cc)));
- double entries[] = {
- -2 * log_likelihood,
- cox,
- cox / (1.0 - exp(initial_log_likelihood * (2 / res->cc)))
- };
- for (size_t i = 0; i < sizeof entries / sizeof *entries; i++)
- pivot_table_put2 (table, i, 0, pivot_value_new_number (entries[i]));
-
- pivot_table_submit (table);
-}
-
-/* Show the case processing summary box */
-static void
-case_processing_summary (const struct lr_result *res)
-{
- struct pivot_table *table = pivot_table_create (
- N_("Case Processing Summary"));
-
- pivot_dimension_create (table, PIVOT_AXIS_COLUMN, N_("Statistics"),
- N_("N"), PIVOT_RC_COUNT,
- N_("Percent"), PIVOT_RC_PERCENT);
-
- struct pivot_dimension *cases = pivot_dimension_create (
- table, PIVOT_AXIS_ROW, N_("Unweighted Cases"),
- N_("Included in Analysis"), N_("Missing Cases"), N_("Total"));
- cases->root->show_label = true;
-
- double total = res->n_nonmissing + res->n_missing;
- struct entry
- {
- int stat_idx;
- int case_idx;
- double x;
- }
- entries[] = {
- { 0, 0, res->n_nonmissing },
- { 0, 1, res->n_missing },
- { 0, 2, total },
- { 1, 0, 100.0 * res->n_nonmissing / total },
- { 1, 1, 100.0 * res->n_missing / total },
- { 1, 2, 100.0 },
- };
- for (size_t i = 0; i < sizeof entries / sizeof *entries; i++)
- pivot_table_put2 (table, entries[i].stat_idx, entries[i].case_idx,
- pivot_value_new_number (entries[i].x));
-
- pivot_table_submit (table);
-}
-
-static void
-output_categories (const struct lr_spec *cmd, const struct lr_result *res)
-{
- struct pivot_table *table = pivot_table_create (
- N_("Categorical Variables' Codings"));
- pivot_table_set_weight_var (table, dict_get_weight (cmd->dict));
-
- int max_df = 0;
- int total_cats = 0;
- for (int i = 0; i < cmd->n_cat_predictors; ++i)
- {
- size_t n = categoricals_n_count (res->cats, i);
- size_t df = categoricals_df (res->cats, i);
- if (max_df < df)
- max_df = df;
- total_cats += n;
- }
-
- struct pivot_dimension *codings = pivot_dimension_create (
- table, PIVOT_AXIS_COLUMN, N_("Codings"),
- N_("Frequency"), PIVOT_RC_COUNT);
- struct pivot_category *coding_group = pivot_category_create_group (
- codings->root, N_("Parameter coding"));
- for (int i = 0; i < max_df; ++i)
- pivot_category_create_leaf_rc (
- coding_group,
- pivot_value_new_user_text_nocopy (xasprintf ("(%d)", i + 1)),
- PIVOT_RC_INTEGER);
-
- struct pivot_dimension *categories = pivot_dimension_create (
- table, PIVOT_AXIS_ROW, N_("Categories"));
-
- int cumulative_df = 0;
- for (int v = 0; v < cmd->n_cat_predictors; ++v)
- {
- int cat;
- const struct interaction *cat_predictors = cmd->cat_predictors[v];
- int df = categoricals_df (res->cats, v);
-
- struct string str = DS_EMPTY_INITIALIZER;
- interaction_to_string (cat_predictors, &str);
- struct pivot_category *var_group = pivot_category_create_group__ (
- categories->root,
- pivot_value_new_user_text_nocopy (ds_steal_cstr (&str)));
-
- for (cat = 0; cat < categoricals_n_count (res->cats, v); ++cat)
- {
- const struct ccase *c = categoricals_get_case_by_category_real (
- res->cats, v, cat);
- struct string label = DS_EMPTY_INITIALIZER;
- for (int x = 0; x < cat_predictors->n_vars; ++x)
- {
- if (!ds_is_empty (&label))
- ds_put_byte (&label, ' ');
-
- const union value *val = case_data (c, cat_predictors->vars[x]);
- var_append_value_name (cat_predictors->vars[x], val, &label);
- }
- int cat_idx = pivot_category_create_leaf (
- var_group,
- pivot_value_new_user_text_nocopy (ds_steal_cstr (&label)));
-
- double *freq = categoricals_get_user_data_by_category_real (
- res->cats, v, cat);
- pivot_table_put2 (table, 0, cat_idx, pivot_value_new_number (*freq));
-
- for (int x = 0; x < df; ++x)
- pivot_table_put2 (table, x + 1, cat_idx,
- pivot_value_new_number (cat == x));
- }
- cumulative_df += df;
- }
-
- pivot_table_submit (table);
-}
-
-static void
-create_classification_dimension (const struct lr_spec *cmd,
- const struct lr_result *res,
- struct pivot_table *table,
- enum pivot_axis_type axis_type,
- const char *label, const char *total)
-{
- struct pivot_dimension *d = pivot_dimension_create (
- table, axis_type, label);
- d->root->show_label = true;
- struct pivot_category *pred_group = pivot_category_create_group__ (
- d->root, pivot_value_new_variable (cmd->dep_var));
- for (int i = 0; i < 2; i++)
- {
- const union value *y = i ? &res->y1 : &res->y0;
- pivot_category_create_leaf_rc (
- pred_group, pivot_value_new_var_value (cmd->dep_var, y),
- PIVOT_RC_COUNT);
- }
- pivot_category_create_leaves (d->root, total, PIVOT_RC_PERCENT);
-}
-
-static void
-output_classification_table (const struct lr_spec *cmd, const struct lr_result *res)
-{
- struct pivot_table *table = pivot_table_create (N_("Classification Table"));
- pivot_table_set_weight_var (table, cmd->wv);
-
- create_classification_dimension (cmd, res, table, PIVOT_AXIS_COLUMN,
- N_("Predicted"), N_("Percentage Correct"));
- create_classification_dimension (cmd, res, table, PIVOT_AXIS_ROW,
- N_("Observed"), N_("Overall Percentage"));
-
- pivot_dimension_create (table, PIVOT_AXIS_ROW, N_("Step"), N_("Step 1"));
-
- struct entry
- {
- int pred_idx;
- int obs_idx;
- double x;
- }
- entries[] = {
- { 0, 0, res->tn },
- { 0, 1, res->fn },
- { 1, 0, res->fp },
- { 1, 1, res->tp },
- { 2, 0, 100 * res->tn / (res->tn + res->fp) },
- { 2, 1, 100 * res->tp / (res->tp + res->fn) },
- { 2, 2,
- 100 * (res->tp + res->tn) / (res->tp + res->tn + res->fp + res->fn)},
- };
- for (size_t i = 0; i < sizeof entries / sizeof *entries; i++)
- {
- const struct entry *e = &entries[i];
- pivot_table_put3 (table, e->pred_idx, e->obs_idx, 0,
- pivot_value_new_number (e->x));
- }
-
- pivot_table_submit (table);
-}