lazy.irtx: Some IRT functions for lazy boys and girls

Description

The following are the classes of the functions.

Item Parameter Estimation and Equating

• uIRT: Item Parameter Estimation of Unidimensional IRT

• ordinal_reg: Oridinal Regression
  
  

• cala: Calibration of Independently Estimated Sets of Item Parameters by Minimizing the LS Criterion Defined in terms of Parameter Values

• calr Calibration of Independently Estimated Sets of Item Parameters by Minimizing the LS Criterion Defined in terms of Probability Values
  
  esttheta: Estimation of Theta

Item Response Functions

• irf Calculation of Item Response Function
  
  

• icrfB: Calculation of item Response Function of Binary Logisticitems

• icrfG: Calculation of item Response Function of Graded Responseitems

• icrfN: Calculation of item Response Function of Nominalitems

• icrfP: Calculation of item Response Function of Partial Credititems

• icrfPN: Calculation of item Response Function of Partial Credititems in Nominal Model Format

• icrfPN0: Calculation of Partial Credit ICRF in Nominal format

Derivative of Item Response Functions

• dirf: Calculation of Derivative of item Response Function
  
  

• dicrfB: Calculation of the Derivative of item Response Function of Binary Logisticitems

• dicrfG: Calculation of the Derivative of item Response Function of Graded Responseitems

• dicrfN: Calculation of the Derivative of item Response Function of Nominalitems

• dicrfP: Calculation of the Derivative of item Response Function of Partial Credititems

• dicrfPN: Calculation of the Derivative of item Response Function of Partial Credititems in Nominal Format

• dicrfPN0: Calculation of the Derivative of Partial Credit ICRF in Nominal format
  
  

• dirf_p: Calculation of the Derivative of item Response Function with respect to Item Parameters

Observed Score Distributions

• obscore: Calculation of Observed Score Distribution and Posterior Distribution of Theta with Various Information Functions
  
  

• smn: Parameter Estimation of Parametric (Normal pdf) Scored Multinomial Distributions

• sumsmnw: Distribution of the Weighted Sum of Several Independent Scored Multinomial Distributions

• sumsmnw12: Distribution of the Weighted Sum of Two Independent Scored Multinomial Distributions

Information Functions

• info_func: Calculation of Various Information Functions

• graded_info: Calculation of the Information Function associated with the Graded Observed Score.

Conversion Functions

• fitG2P: Approximate Conversion of Partial Credititems to Graded Responseitems Using Logit Transformation

• fitP2G: Approximate Conversion of Graded Responseitems to Partial Credititems Using Logit Transformation
  
  

• convP2N: Convert Partial Credit Item Parameters to in Nominal Format

• convP2PN: Convert Partial Credit Item Parameters in Standard Format to Partial Credit Parameters in Nominal Format

• convPN2P: Convert Partial Credit Item Parameters in Nominal Format to Standard Format

Reading Item Paramter File

• read.param: Reading Parameter File

• read.weight: Reading Weight File

Utility Functions for IRT

• checkparam: Checking Parameter Data Frame

• gendataIRT: Generation of Simulated Item Response Data

• dummy_expand: Dummmy Expantion of Categorical Data

• find_mode: Find the Mode of icrf

• find_intersection: Find the Intersection of icrfs

Data

• paramB1: Binary Item Parameter Data Frame # 1. (18 2PLM items)

• paramB2: Binary Item Parameter Data Frame # 2. (18 3PLM items)
  
  

• paramS1: Small Item Parameter Data Frame # 1. (3 mixed type items)

• paramS2: Small Item Parameter Data Frame # 2. (8 mixed type items)

• paramS3: Small Item Parameter Data Frame # 2. (20 mixed type items)
  
  

• weightS1: Small Item Weight Data Frame # 1 To be used in conjunction with paramS1.

• weightS11: Small Item Weight Data Frame # 2. To be used in conjunction with paramS1.

• weightS12: Small Item Weight Data Frame # 3. To be used in conjunction with paramS1.

• weightS2: Small Item Weight Data Frame # 4. To be used in conjunction with paramS2.

• weightS21: Small Item Weight Data Frame # 5. To be used in conjunction with paramS2.

• weightS22: Small Item Weight Data Frame # 6. To be used in conjunction with paramS2.

• weightS3: Small Item Weight Data Frame # 7. To be used in conjunction with paramS3.
  
  

• paramCal1: Small Item Parameter Data Frame for Testing cala and calr #1.

• paramCal2: Small Item Parameter Data Frame for Testing cala and calr #2.

Functions from lazy.tools package

See the help files for details.

• comments

• princ

• named_list

• wquantile

• fuzz

• decp

• get_range

• rmv

• Print

• is.varname

• interpol

• trim

• ceiling_n

• cards

Functions from lazy.mat package

See the help files for details.

• matSwp

• chkginv

• pmat

• Mh2Mv

• vecdiag

• Diag

• b_diag