Deletion or selection of persons from a test to be analyzed, but without removing their responses from your data file, is easily accomplished by creating a file in which each line contains the sequence number of a person or persons to be deleted or selected (according to the same rules given under IDFILE=), and then specifying this file by means of the control variable, PDFILE=, or enter the deletion list in the control file using PDFILE=*. PDFILE= can be action from the Specification menu dialog box.

 

 

Example 1: You wish to delete the fifth and tenth persons from this analysis.

1. Create a file named, say, "PERSON.DEL"

  2. Enter into the file, the lines:

5

10

3. Specify, in the control file,

PDFILE=PERSON.DEL

 

 or, enter directly into the control file,

   PDFILE=*

   5

   10

   *

 

Example 2: The analyst wants to delete the most misfitting persons reported in Table 6.

1. Set up a standard control file.

2. Specify

PDFILE=*

*

3. Copy the target portion of Table 6.

4. Paste it between the "*"

5. Delete characters before the entry numbers.

6. Type ; after the entry numbers to make further numbers into comments.

 

Example 3:

TITLE = 'Example of person deletion list from Table 6'

PDFILE = *

 Delete the border character before the entry number

; ENTRY   RAW                          INFIT     OUTFIT              

;   NUM  SCORE COUNT MEASURE  ERROR MNSQ  ZSTD MNSQ  ZSTD PTBSE  PUP 

   73   ; 21    22      .14     .37  .95   -.3 1.03    .2 B-.19  SAN 

   75   ; 16    22     -.56     .39  .95   -.3 1.03    .2 C-.19  PAU 

        Enter the ; to make other numbers into comments

*    ; closure of PDFILE=*

 

 

Example 4: My sample is large enough (n>2000). I want to exclude in the analysis the persons and items that have infit or outfit statistics of less than -2 or greater than +2.

 

1. Perform your analysis.

2. Output files menu: PFILE to Excel.

3. In Excel sort the persons in Outfit ZSTD order.

4. Delete all person rows you want to keep in your analysis.

5. Copy the column of entry numbers of persons you want to delete.

6. Create a new text file "delete.txt"

7. Paste the list of entry numbers into the text file

8. In your Winsteps control file, add

PDFILE = delete.txt

9. Perform your revised analysis