Example 9: Grouping and modeling items

A 20 item test. Items 1, 2 are dichotomous items, coded "Y", "N". Item 3 is a "Partial Credit" item. Items 4-10 are all ratings on one Andrich scale or test-level partial-credit scale (Grouping 1), and items 11-20 are all ratings on another Andrich scale or test-level partial-credit scale (Grouping 2). These are grouped with ISGROUPS=. Winsteps discovers from the data what the item structure is. Items 3-20 have response codes "A", "B", "C", "D", "E" or "a", "b", "c", "d", "e".

; This file is EXAM9.TXT

TITLE="Grouping and Modeling"

ITEM1=11                ; Item responses start in column 11

NI=20                        ; There are 20 items

ISGROUPS=DD011111112222222222        ; The groupings in item order

IREFER=DDAAAAAAAAAAAAAAAAAA        ; for recoding

CODES  = 10ABCDEabcde                ; Response codes to all items

IVALUED= 10**********                ; for Items 1 & 2

IVALUEA= **1234512345                ; for Items 3-20

DATA=EXAM9DAT.TXT                        ; Location of data file

IWEIGHT=*                                ; Item weighting file list

3 2.5                                        ; Item 3 has weight of 2.5

*

&END

RD Prompt 1        ; Item id's remind us of MODELS= and ISGROUPS=

RD Prompt 2        ; MODELS= and ISGROUPS= are shown in item measure Tables 10, 13, 14, 15

S0 Logic

R1 Grammar 1

R1 Grammar 2

R1 Grammar 3

R1 Grammar 4

R1 Grammar 5

R1 Grammar 6

R1 Grammar 7

R2 Meaning 1

R2 Meaning 2

R2 Meaning 3

R2 Meaning 4

R2 Meaning 5

R2 Meaning 6

R2 Meaning 7

R2 Meaning 8

R2 Meaning 9

R2 Meaning 10

END NAMES

The data is in file EXAM9DAT.TXT:

Richard M 00bCDCDddCDddddCDccE

Tracie  F 00BcBABBccbBbbBbBBBb

 .

James   M 00ccaBbabBAcbacbaBbb

Joe     M 10BdBBBBccBccbbccbcC