You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
- 02111-1307, USA. */
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ 02110-1301, USA. */
#include <config.h>
#include <gsl/gsl_cdf.h>
#include "str.h"
#include "case.h"
#include "command.h"
+#include "dictionary.h"
#include "lexer.h"
#include "error.h"
#include "magic.h"
#include "var.h"
#include "vfm.h"
#include "hash.h"
-#include "t-test.h"
+#include "group_proc.h"
#include "casefile.h"
#include "levene.h"
+/* (headers) */
/* (specification)
"T-TEST" (tts_):
+groups=custom;
- +testval=double;
+ testval=double;
variables=varlist("PV_NO_SCRATCH | PV_NUMERIC");
pairs=custom;
+missing=miss:!analysis/listwise,
/* Variable for the GROUPS subcommand, if given. */
static struct variable *indep_var;
-/* GROUPS: Number of values specified by the user; the values
- specified if any. */
+enum comparison
+ {
+ CMP_LE = -2,
+ CMP_EQ = 0,
+ };
+
+struct group_properties
+{
+ /* The comparison criterion */
+ enum comparison criterion;
+
+ /* The width of the independent variable */
+ int indep_width ;
+
+ union {
+ /* The value of the independent variable at which groups are determined to
+ belong to one group or the other */
+ double critical_value;
+
+
+ /* The values of the independent variable for each group */
+ union value g_value[2];
+ } v ;
+
+};
+
-static int n_group_values;
-static union value groups_values[2];
-static enum comparison criteria[2];
+static struct group_properties gp ;
static void group_postcalc (struct cmd_t_test *);
-static int compare_var_name (const void *a_, const void *b_, void *v_ UNUSED);
-static unsigned hash_var_name (const void *a_, void *v_ UNUSED);
-
static void calculate(const struct casefile *cf, void *_mode);
static int mode;
static int bad_weight_warn;
+
+static int compare_group_binary(const struct group_statistics *a,
+ const struct group_statistics *b,
+ const struct group_properties *p);
+
+
+static unsigned hash_group_binary(const struct group_statistics *g,
+ const struct group_properties *p);
+
+
+
int
cmd_t_test(void)
{
msg(SE,
_("TESTVAL, GROUPS and PAIRS subcommands are mutually exclusive.")
);
+ free_t_test(&cmd);
return CMD_FAILURE;
}
}
if (cmd.sbc_variables)
{
msg(SE, _("VARIABLES subcommand is not appropriate with PAIRS"));
+ free_t_test(&cmd);
return CMD_FAILURE;
}
else
struct hsh_table *hash;
struct variable *v;
- hash=hsh_create(n_pairs,compare_var_name,hash_var_name,0,0);
+ hash = hsh_create (n_pairs, compare_var_names, hash_var_name, 0, 0);
for (i=0; i < n_pairs; ++i)
{
else if ( !cmd.sbc_variables)
{
msg(SE, _("One or more VARIABLES must be specified."));
+ free_t_test(&cmd);
return CMD_FAILURE;
}
if ( mode == T_IND_SAMPLES)
{
- int i;
+ int v;
/* Destroy any group statistics we created */
- for (i= 0 ; i < cmd.n_variables ; ++i )
+ for (v = 0 ; v < cmd.n_variables ; ++v )
{
- free(cmd.v_variables[i]->p.t_t.gs);
+ struct group_proc *grpp = group_proc_get (cmd.v_variables[v]);
+ hsh_destroy (grpp->group_hash);
}
}
+ free_t_test(&cmd);
return CMD_SUCCESS;
}
static int
tts_custom_groups (struct cmd_t_test *cmd UNUSED)
{
+ int n_group_values=0;
lex_match('=');
{
if (indep_var->type == NUMERIC)
{
- groups_values[0].f = 1;
- groups_values[1].f = 2;
- criteria[0] = criteria[1] = CMP_EQ;
+ gp.v.g_value[0].f = 1;
+ gp.v.g_value[1].f = 2;
+
+ gp.criterion = CMP_EQ;
+
n_group_values = 2;
+
return 1;
}
else
{
- msg (SE, _("When applying GROUPS to a string variable, at "
- "least one value must be specified."));
+ msg (SE, _("When applying GROUPS to a string variable, two "
+ "values must be specified."));
return 0;
}
}
- if (!parse_value (&groups_values[0],indep_var->type))
+ if (!parse_value (&gp.v.g_value[0], indep_var->type))
return 0;
lex_match (',');
if (lex_match (')'))
{
- criteria[0] = CMP_LE;
- criteria[1] = CMP_GT;
- groups_values[1] = groups_values[0];
+ if (indep_var->type != NUMERIC)
+ {
+
+ msg (SE, _("When applying GROUPS to a string variable, two "
+ "values must be specified."));
+ return 0;
+ }
+ gp.criterion = CMP_LE;
+ gp.v.critical_value = gp.v.g_value[0].f;
+
n_group_values = 1;
return 1;
}
- if (!parse_value (&groups_values[1],indep_var->type))
+ if (!parse_value (&gp.v.g_value[1], indep_var->type))
return 0;
-
+
n_group_values = 2;
if (!lex_force_match (')'))
return 0;
- criteria[0] = criteria[1] = CMP_EQ;
+ if ( n_group_values == 2 )
+ gp.criterion = CMP_EQ ;
+ else
+ gp.criterion = CMP_LE ;
+
+
return 1;
}
void ssbox_paired_init(struct ssbox *this,
struct cmd_t_test *cmd);
+
/* Factory to create an ssbox */
void
ssbox_create(struct ssbox *ssb, struct cmd_t_test *cmd, int mode)
}
+
/* Despatcher for the populate method */
void
ssbox_populate(struct ssbox *ssb,struct cmd_t_test *cmd)
tab_submit(ssb->t);
}
+
+
/* Initialize a ssbox struct */
void
ssbox_base_init(struct ssbox *this, int cols,int rows)
char *val_lab0=0;
char *val_lab1=0;
+ double indep_value[2];
char prefix[2][3]={"",""};
if ( indep_var->type == NUMERIC )
{
- val_lab0 = val_labs_find( indep_var->val_labs,groups_values[0]);
- val_lab1 = val_labs_find( indep_var->val_labs,groups_values[1]);
+ val_lab0 = val_labs_find( indep_var->val_labs,gp.v.g_value[0]);
+ val_lab1 = val_labs_find( indep_var->val_labs,gp.v.g_value[1]);
}
else
{
- val_lab0 = groups_values[0].s;
- val_lab1 = groups_values[1].s;
+ val_lab0 = gp.v.g_value[0].s;
+ val_lab1 = gp.v.g_value[1].s;
}
- if (n_group_values == 1)
+ if (gp.criterion == CMP_LE )
{
strcpy(prefix[0],"< ");
strcpy(prefix[1],">=");
+ indep_value[0] = gp.v.critical_value;
+ indep_value[1] = gp.v.critical_value;
+ }
+ else
+ {
+ indep_value[0] = gp.v.g_value[0].f;
+ indep_value[1] = gp.v.g_value[1].f;
}
assert(ssb->t);
for (i=0; i < cmd->n_variables; ++i)
{
- int g;
+ struct variable *var = cmd->v_variables[i];
+ struct hsh_table *grp_hash = group_proc_get (var)->group_hash;
+ int count=0;
tab_text (ssb->t, 0, i*2+1, TAB_LEFT, cmd->v_variables[i]->name);
tab_text (ssb->t, 1, i*2+1, TAB_LEFT | TAT_PRINTF,
"%s%s", prefix[0], val_lab0);
else
- tab_text (ssb->t, 1, i*2+1, TAB_LEFT | TAT_PRINTF,
- "%s%g", prefix[0], groups_values[0].f);
+ tab_text (ssb->t, 1, i*2+1, TAB_LEFT | TAT_PRINTF,
+ "%s%g", prefix[0], indep_value[0]);
if (val_lab1)
tab_text (ssb->t, 1, i*2+1+1, TAB_LEFT | TAT_PRINTF,
"%s%s", prefix[1], val_lab1);
else
- tab_text (ssb->t, 1, i*2+1+1, TAB_LEFT | TAT_PRINTF,
- "%s%g", prefix[1], groups_values[1].f);
+ tab_text (ssb->t, 1, i*2+1+1, TAB_LEFT | TAT_PRINTF,
+ "%s%g", prefix[1], indep_value[1]);
+
/* Fill in the group statistics */
- for ( g=0; g < 2 ; ++g )
+ for ( count = 0 ; count < 2 ; ++count )
{
- struct group_statistics *gs = &cmd->v_variables[i]->p.t_t.gs[g];
+ union value search_val;
+
+ struct group_statistics *gs;
- tab_float(ssb->t, 2 ,i*2+g+1, TAB_RIGHT, gs->n, 2, 0);
- tab_float(ssb->t, 3 ,i*2+g+1, TAB_RIGHT, gs->mean, 8, 2);
- tab_float(ssb->t, 4 ,i*2+g+1, TAB_RIGHT, gs->std_dev, 8, 3);
- tab_float(ssb->t, 5 ,i*2+g+1, TAB_RIGHT, gs->se_mean, 8, 3);
+ if ( gp.criterion == CMP_LE )
+ {
+ if ( count == 0 )
+ {
+ /* less than ( < ) case */
+ search_val.f = gp.v.critical_value - 1.0;
+ }
+ else
+ {
+ /* >= case */
+ search_val.f = gp.v.critical_value + 1.0;
+ }
+ }
+ else
+ {
+ search_val = gp.v.g_value[count];
+ }
+
+ gs = hsh_find(grp_hash, (void *) &search_val);
+ assert(gs);
+
+ tab_float(ssb->t, 2 ,i*2+count+1, TAB_RIGHT, gs->n, 2, 0);
+ tab_float(ssb->t, 3 ,i*2+count+1, TAB_RIGHT, gs->mean, 8, 2);
+ tab_float(ssb->t, 4 ,i*2+count+1, TAB_RIGHT, gs->std_dev, 8, 3);
+ tab_float(ssb->t, 5 ,i*2+count+1, TAB_RIGHT, gs->se_mean, 8, 3);
}
}
}
{
struct group_statistics *gs;
- gs=&pairs[i].v[j]->p.t_t.ugs;
+ gs = &group_proc_get (pairs[i].v[j])->ugs;
/* Titles */
for (i=0; i < cmd->n_variables; ++i)
{
- struct group_statistics *gs;
- gs= &cmd->v_variables[i]->p.t_t.ugs;
+ struct group_statistics *gs = &group_proc_get (cmd->v_variables[i])->ugs;
tab_text (ssb->t, 0, i+1, TAB_LEFT, cmd->v_variables[i]->name);
tab_float (ssb->t,1, i+1, TAB_RIGHT, gs->n, 2, 0);
double std_err_diff;
double mean_diff;
- struct group_statistics *gs0 = &cmd->v_variables[i]->p.t_t.gs[0];
- struct group_statistics *gs1 = &cmd->v_variables[i]->p.t_t.gs[1];
+ struct variable *var = cmd->v_variables[i];
+ struct group_proc *grp_data = group_proc_get (var);
+
+ struct hsh_table *grp_hash = grp_data->group_hash;
+
+ struct group_statistics *gs0 ;
+ struct group_statistics *gs1 ;
+
+ union value search_val;
+
+ if ( gp.criterion == CMP_LE )
+ search_val.f = gp.v.critical_value - 1.0;
+ else
+ search_val = gp.v.g_value[0];
+
+ gs0 = hsh_find(grp_hash, (void *) &search_val);
+ assert(gs0);
+
+ if ( gp.criterion == CMP_LE )
+ search_val.f = gp.v.critical_value + 1.0;
+ else
+ search_val = gp.v.g_value[1];
+
+ gs1 = hsh_find(grp_hash, (void *) &search_val);
+ assert(gs1);
+
tab_text (self->t, 0, i*2+3, TAB_LEFT, cmd->v_variables[i]->name);
tab_text (self->t, 1, i*2+3, TAB_LEFT, _("Equal variances assumed"));
- tab_float(self->t, 2, i*2+3, TAB_CENTER,
- cmd->v_variables[i]->p.t_t.levene, 8,3);
+ tab_float(self->t, 2, i*2+3, TAB_CENTER, grp_data->levene, 8,3);
/* Now work out the significance of the Levene test */
- df1 = 1; df2 = cmd->v_variables[i]->p.t_t.ugs.n - 2;
- q = gsl_cdf_fdist_Q(cmd->v_variables[i]->p.t_t.levene, df1, df2);
+ df1 = 1; df2 = grp_data->ugs.n - 2;
+ q = gsl_cdf_fdist_Q(grp_data->levene, df1, df2);
tab_float(self->t, 3, i*2+3, TAB_CENTER, q, 8,3 );
tab_vline(self->t, TAL_2, 1, 0, vsize - 1);
tab_joint_text(self->t, 1, 0, hsize-1,0, TAB_CENTER | TAT_PRINTF,
- _("Test Value = %f"),cmd->n_testval);
+ _("Test Value = %f"), cmd->n_testval[0]);
tab_box(self->t, -1, -1, -1, TAL_1, 1,1,hsize-1,vsize-1);
double t;
double p,q;
double df;
- struct group_statistics *gs;
- gs= &cmd->v_variables[i]->p.t_t.ugs;
+ struct group_statistics *gs = &group_proc_get (cmd->v_variables[i])->ugs;
tab_text (trb->t, 0, i+3, TAB_LEFT, cmd->v_variables[i]->name);
- t = (gs->mean - cmd->n_testval ) * sqrt(gs->n) / gs->std_dev ;
+ t = (gs->mean - cmd->n_testval[0] ) * sqrt(gs->n) / gs->std_dev ;
tab_float (trb->t, 1, i+3, TAB_RIGHT, t, 8,3);
+
/* Calculation Implementation */
/* Per case calculations common to all variants of the T test */
struct variable *v = cmd->v_variables[i];
const union value *val = case_data (c, v->fv);
- gs= &cmd->v_variables[i]->p.t_t.ugs;
+ gs= &group_proc_get (cmd->v_variables[i])->ugs;
if (! value_is_missing(val,v) )
{
for(i=0; i< cmd->n_variables ; ++i)
{
struct group_statistics *gs;
- gs= &cmd->v_variables[i]->p.t_t.ugs;
+ gs= &group_proc_get (cmd->v_variables[i])->ugs;
gs->sum=0;
gs->n=0;
for(i=0; i< cmd->n_variables ; ++i)
{
struct group_statistics *gs;
- gs= &cmd->v_variables[i]->p.t_t.ugs;
+ gs= &group_proc_get (cmd->v_variables[i])->ugs;
gs->mean=gs->sum / gs->n;
gs->s_std_dev= sqrt(
struct variable *v = cmd->v_variables[i];
const union value *val = case_data (c, v->fv);
- gs= &cmd->v_variables[i]->p.t_t.ugs;
+ gs= &group_proc_get (cmd->v_variables[i])->ugs;
if ( ! value_is_missing(val,v))
- gs->sum_diff += weight * (val->f - cmd->n_testval);
+ gs->sum_diff += weight * (val->f - cmd->n_testval[0]);
}
return 0;
for(i=0; i< cmd->n_variables ; ++i)
{
struct group_statistics *gs;
- gs= &cmd->v_variables[i]->p.t_t.ugs;
+ gs= &group_proc_get (cmd->v_variables[i])->ugs;
gs->sum_diff=0;
}
for(i=0; i< cmd->n_variables ; ++i)
{
struct group_statistics *gs;
- gs= &cmd->v_variables[i]->p.t_t.ugs;
+ gs= &group_proc_get (cmd->v_variables[i])->ugs;
gs->mean_diff = gs->sum_diff / gs->n ;
}
-static int
-compare_var_name (const void *a_, const void *b_, void *v_ UNUSED)
-{
- const struct variable *a = a_;
- const struct variable *b = b_;
-
- return strcmp(a->name,b->name);
-}
-
-static unsigned
-hash_var_name (const void *a_, void *v_ UNUSED)
-{
- const struct variable *a = a_;
-
- return hsh_hash_bytes (a->name, strlen(a->name));
-}
-
-
-
static void
paired_precalc (struct cmd_t_test *cmd UNUSED)
{
}
}
-/* Return the group # corresponding to the
- independent variable with the value val
-*/
-static int
-get_group(const union value *val, struct variable *indep)
-{
- int i;
-
- for (i = 0; i < 2 ; ++i )
- {
- const int cmp = compare_values(val,&groups_values[i],indep->width) ;
- switch ( criteria[i])
- {
- case CMP_EQ:
- if ( 0 == cmp ) return i;
- break;
- case CMP_LT:
- if ( 0 > cmp ) return i;
- break;
- case CMP_LE:
- if ( cmp <= 0 ) return i;
- break;
- case CMP_GT:
- if ( cmp > 0 ) return i;
- break;
- case CMP_GE:
- if ( cmp >= 0 ) return i;
- break;
- default:
- assert(0);
- };
- }
-
- /* No groups matched */
- return -1;
-}
-
-
static void
group_precalc (struct cmd_t_test *cmd )
{
for(i=0; i< cmd->n_variables ; ++i)
{
- struct t_test_proc *ttpr = &cmd->v_variables[i]->p.t_t;
+ struct group_proc *ttpr = group_proc_get (cmd->v_variables[i]);
/* There's always 2 groups for a T - TEST */
ttpr->n_groups = 2;
- ttpr->gs = xmalloc(sizeof(struct group_statistics) * 2) ;
+
+ gp.indep_width = indep_var->width;
+
+ ttpr->group_hash = hsh_create(2,
+ (hsh_compare_func *) compare_group_binary,
+ (hsh_hash_func *) hash_group_binary,
+ (hsh_free_func *) free_group,
+ (void *) &gp );
for (j=0 ; j < 2 ; ++j)
{
- ttpr->gs[j].sum = 0;
- ttpr->gs[j].n = 0;
- ttpr->gs[j].ssq = 0;
+
+ struct group_statistics *gs = (struct group_statistics *)
+ xmalloc (sizeof(struct group_statistics));
+
+ gs->sum = 0;
+ gs->n = 0;
+ gs->ssq = 0;
- if ( n_group_values == 2 )
- ttpr->gs[j].id = groups_values[j];
+ if ( gp.criterion == CMP_EQ )
+ {
+ gs->id = gp.v.g_value[j];
+ }
else
- ttpr->gs[j].id = groups_values[0];
- ttpr->gs[j].criterion = criteria[j];
+ {
+ if ( j == 0 )
+ gs->id.f = gp.v.critical_value - 1.0 ;
+ else
+ gs->id.f = gp.v.critical_value + 1.0 ;
+ }
+
+ hsh_insert ( ttpr->group_hash, (void *) gs );
+
}
}
group_calc (const struct ccase *c, struct cmd_t_test *cmd)
{
int i;
- int g;
const union value *gv = case_data (c, indep_var->fv);
}
}
-
gv = case_data (c, indep_var->fv);
- g = get_group(gv,indep_var);
-
-
- /* If the independent variable doesn't match either of the values
- for this case then move on to the next case */
- if (g == -1 )
- return 0;
-
for(i=0; i< cmd->n_variables ; ++i)
{
struct variable *var = cmd->v_variables[i];
+ const union value *val = case_data (c, var->fv);
+ struct hsh_table *grp_hash = group_proc_get (var)->group_hash;
+ struct group_statistics *gs;
- struct group_statistics *gs = &var->p.t_t.gs[g];
+ gs = hsh_find(grp_hash, (void *) gv);
- const union value *val = case_data (c, var->fv);
+ /* If the independent variable doesn't match either of the values
+ for this case then move on to the next case */
+ if ( ! gs )
+ return 0;
if ( !value_is_missing(val,var) )
{
group_postcalc ( struct cmd_t_test *cmd )
{
int i;
- int j;
for(i=0; i< cmd->n_variables ; ++i)
{
- for (j=0 ; j < 2 ; ++j)
- {
- struct group_statistics *gs;
- gs=&cmd->v_variables[i]->p.t_t.gs[j];
+ struct variable *var = cmd->v_variables[i];
+ struct hsh_table *grp_hash = group_proc_get (var)->group_hash;
+ struct hsh_iterator g;
+ struct group_statistics *gs;
+ int count=0;
+ for (gs = hsh_first (grp_hash,&g);
+ gs != 0;
+ gs = hsh_next(grp_hash,&g))
+ {
gs->mean = gs->sum / gs->n;
gs->s_std_dev= sqrt(
- ( (gs->ssq / gs->n ) - gs->mean * gs->mean )
- ) ;
+ ( (gs->ssq / gs->n ) - gs->mean * gs->mean )
+ ) ;
gs->std_dev= sqrt(
- gs->n/(gs->n-1) *
- ( (gs->ssq / gs->n ) - gs->mean * gs->mean )
- ) ;
+ gs->n/(gs->n-1) *
+ ( (gs->ssq / gs->n ) - gs->mean * gs->mean )
+ ) ;
gs->se_mean = gs->std_dev / sqrt(gs->n);
+ count ++;
}
+ assert(count == 2);
}
}
casereader_destroy (r);
group_postcalc(cmd);
-
levene(cf, indep_var, cmd->n_variables, cmd->v_variables,
(cmd->miss == TTS_LISTWISE)?LEV_LISTWISE:LEV_ANALYSIS ,
value_is_missing);
trbox_finalize(&test_results_box);
}
+
+short which_group(const struct group_statistics *g,
+ const struct group_properties *p);
+
+/* Return -1 if the id of a is less than b; +1 if greater than and
+ 0 if equal */
+static int
+compare_group_binary(const struct group_statistics *a,
+ const struct group_statistics *b,
+ const struct group_properties *p)
+{
+ short flag_a;
+ short flag_b;
+
+ if ( p->criterion == CMP_LE )
+ {
+ /* less-than-or-equal comparision is not meaningfull for
+ alpha variables, so we shouldn't ever arrive here */
+ assert(p->indep_width == 0 ) ;
+
+ flag_a = ( a->id.f < p->v.critical_value ) ;
+ flag_b = ( b->id.f < p->v.critical_value ) ;
+ }
+ else
+ {
+ flag_a = which_group(a, p);
+ flag_b = which_group(b, p);
+ }
+
+ if (flag_a < flag_b )
+ return -1;
+
+ return (flag_a > flag_b);
+}
+
+/* This is a degenerate case of a hash, since it can only return three possible
+ values. It's really a comparison, being used as a hash function */
+
+static unsigned
+hash_group_binary(const struct group_statistics *g,
+ const struct group_properties *p)
+{
+ short flag = -1;
+
+ if ( p->criterion == CMP_LE )
+ {
+ /* Not meaningfull to do a less than compare for alpha values ? */
+ assert(p->indep_width == 0 ) ;
+ flag = ( g->id.f < p->v.critical_value ) ;
+ }
+ else if ( p->criterion == CMP_EQ)
+ {
+ flag = which_group(g,p);
+ }
+ else
+ assert(0);
+
+ return flag;
+}
+
+/* return 0 if G belongs to group 0,
+ 1 if it belongs to group 1,
+ 2 if it belongs to neither group */
+short
+which_group(const struct group_statistics *g,
+ const struct group_properties *p)
+{
+
+ if ( 0 == compare_values (&g->id, &p->v.g_value[0], p->indep_width))
+ return 0;
+
+ if ( 0 == compare_values (&g->id, &p->v.g_value[1], p->indep_width))
+ return 1;
+
+ return 2;
+}
+