mirt.c File Reference

A command line program to estimate items and abilities in a multiple choice IRT model. More...

#include <libirt.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <getopt.h>
#include <string.h>

Functions
int	parse_arg (int argc, char *argv[])
	Parse the options and arguments of the program.
int	options_weights_from_answer_key (char *answer_key, gsl_vector_int *items_pos, gsl_vector_int *nbr_options, gsl_vector *options_weights)
	Parse the answer key and set the options weights.
int	main (int argc, char *argv[])
	The main function of the program.

Variables
struct option	long_options []
	The command line options.
char *	file_name
	The file name.
int	nbr_item
	The number of item.
int	nbr_subject
	The number of subject.
int	skip
	The number of line to skip.
int	offset
	The number of character or field to skip.
int	extra
	The number of character or field between items.
char	delimiter
	The delimiter.
char *	answer_key
	The option representing sucess for each item.
int	nbr_quad
	The number of quadrature class.
double	quad_from
	The first class middle point.
double	quad_to
	The last class middle point.
double	slope_init
	The initial value of the slope.
double	thresh_init
	The initial value of the threshold.
int	max_em_iter
	The maximum number of EM iteration.
int	max_nr_iter
	The maximum number of newton iteration.
double	precision
	The precision.
int	grouping
	Enable the grouping of identical patterns.
int	verbose
	The verbosity level.
int	ability
	Enable the estimation of the abilities.
int	trimming
	Enable the trimming of spaces in the fields (when delimited).
int	penalized
	Enable the use of penalized maximum marginal likelihood.
int	kernel
	Enable the use of kernel estimators.
double	smooth_factor
	The smooth factor if PMMLE or kernel is used.
int	response_functions
	Enable the display of the response functions instead of the parameters.
int	graded
	Enable the use of the graded model.
int	icc
	Enable the display of the items' characteristic curves.

Detailed Description

A command line program to estimate items and abilities in a multiple choice IRT model.

Author

Stephane Germain germs.nosp@m.te@g.nosp@m.mail..nosp@m.com

Function Documentation

int parse_arg	(	int	argc,
		char *	argv[]
	)

Parse the options and arguments of the program.

Also set the defaults values.

Returns

1 for success and 0 for failure.

int options_weights_from_answer_key	(	char *	answer_key,
		gsl_vector_int *	items_pos,
		gsl_vector_int *	nbr_options,
		gsl_vector *	options_weights
	)

Parse the answer key and set the options weights.

Returns

1 for success and 0 for failure.

int main	(	int	argc,
		char *	argv[]
	)

The main function of the program.

Variable Documentation

struct option long_options[]

Initial value:

 {
  {"help", no_argument, 0, 'h'},
  {"version", no_argument, 0, 'v'},
  {"nbr_item", required_argument, 0, 'i'},
  {"nbr_subject", required_argument, 0, 'j'},
  {"skip", required_argument, 0, 'k'},
  {"offset", required_argument, 0, 'o'},
  {"extra", required_argument, 0, 'x'},
  {"delimiter", required_argument, 0, 'd'},
  {"nbr_quad", required_argument, 0, 'q'},
  {"penalized", no_argument, 0, 'P'},
  {"kernel", no_argument, 0, 'K'},
  {"smooth_factor", required_argument, 0, 's'},
  {"max_em_iter", required_argument, 0, 'e'},
  {"max_nr_iter", required_argument, 0, 'n'},
  {"response_functions", required_argument, 0, 'R'},
  {"grouping", no_argument, 0, 'G'},
  {"verbose", no_argument, 0, 'V'},
  {"ability", no_argument, 0, 'A'},
  {"quad_from", required_argument, 0, 11},
  {"quad_to", required_argument, 0, 12},
  {"answer_key", required_argument, 0, 'W'},
  {"trimming", no_argument, 0, 'T'},
  {"slope_init", required_argument, 0, 16},
  {"thresh_init", required_argument, 0, 17},
  {"precision", required_argument, 0, 19},
  {"graded", no_argument, 0, 'g'},
  {"icc", no_argument, 0, 'I'},
  {0, 0, 0, 0}
}

The command line options.

To be used by getopt_long.

char* file_name

The file name.

int nbr_item

The number of item.

int nbr_subject

The number of subject.

int skip

The number of line to skip.

int offset

The number of character or field to skip.

int extra

The number of character or field between items.

char delimiter

The delimiter.

char* answer_key

The option representing sucess for each item.

int nbr_quad

The number of quadrature class.

double quad_from

The first class middle point.

double quad_to

The last class middle point.

double slope_init

The initial value of the slope.

double thresh_init

The initial value of the threshold.

int max_em_iter

The maximum number of EM iteration.

int max_nr_iter

The maximum number of newton iteration.

double precision

The precision.

int grouping

Enable the grouping of identical patterns.

int verbose

The verbosity level.

int ability

Enable the estimation of the abilities.

int trimming

Enable the trimming of spaces in the fields (when delimited).

int penalized

Enable the use of penalized maximum marginal likelihood.

int kernel

Enable the use of kernel estimators.

double smooth_factor

The smooth factor if PMMLE or kernel is used.

int response_functions

Enable the display of the response functions instead of the parameters.

int graded

Enable the use of the graded model.

int icc

Enable the display of the items' characteristic curves.