mirt (version 0.2.6)

confmirt.model: Specify confirmatory loadings

Description

The confmirt.model function scans user input to specify the confirmatory model.

Usage

confmirt.model(file = "", ...)

Arguments

file

a string specifying an external file that declares the input.

...

additional arguments for scan()

Value

• Returns a model specification object to be used in confmirt.

Details

Factors are first named and then specify which numerical items they affect (i.e., where the slope is not equal to 0), separated either by commas or by - to indicate a range of items. Products between factors may be specified by enclosing the left hand term within brackets. To finish the declaration of a model simply enter a blank line with only a carriage return (i.e., the 'enter' or 'return' key). There are six optional keyword for specifying the relationships between factors, item parameters, and prior distributions. Note that all independent terms must be separated with a comma. These are: [object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Examples

model <- confmirt.model()
  F1 = 1,2,3,4-10
  F2 = 10-20
  (F1*F1) = 1,2,3,4-10
  COV = F1*F2
  PARTCOMP = 10
  SLOPE = F1@1 eq F1@2
  MEAN = F1 eq 1, F2 eq -1
  INT = 1@1 eq -0.5
  PRIOR = N(0,4)@1