﻿ Recoding non-numeric and other data values

# Recoding non-numeric and other data values

Each observation is expected to be a numerical rating or a count of events, but non-numeric codes can be used, if they are recoded in a Rating (or partial credit) scale= specification. Numeric values can also be recoded to other values.

Blank observations in the data file are ignored. Leading and trailing blanks are removed from recorded observations before they are compared with recoded values. The data value of "+" is invalid.

Example 1:

Person 23 made 8 spelling mistakes in Essay 5. No recoding is required.

data=

23,5,8 ; 8 is the count of errors

Example 2:

The correct answer to item 3 is "B", but "A", "C", "D", and "*" are incorrect

Model=?,3,Item3 ; Item 3 has a unique model and rating scale (or partial credit)

Rating (or partial credit) scale=Item3,D ; define a dichotomous item

0,Wrong,,,A+C+D+* ; recode all "wrong" codes to 0
; ",,," indicates logit value and anchor status are omitted

1,Right,,,B ; recode correct, "B" to 1

*

data=

5,3,A ; Person 5 on Item 3 responded "A"

6,3,D ; Person 6 on Item 3 responded "D"

Example 3: A rating scale originally coded 1 through 6 is to be recoded 0,1,2

Model=?,?,Scale ; "Scale" is to be redefined

Rating (or partial credit) scale=Scale,R2 ;define scale as 0,1,2

0,Low,,,1+2 ; recode 1 and 2 to 0. ",,," omits logit value and anchor status

1,Medium,,,3+4+5 ; recode 3,4,5 to 1

2,High,,,6 ; recode 6 to 2

*

data=

13,5-8,4,5,2,6 ; Person 13's responses to items 5 through 8 were 4,5,2,6,
; recoded 1,1,0,2

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