ISELECT= item selection criterion = *, all items

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Items to be selected may be specified by using the ISELECT= instruction to match characters within the item name. Items deleted by IDFILE= or similar are never selected by ISELECT=.

 

This can be done before analysis in the control file or with "Extra specifications". It can also be done after the analysis using the "Specification" pull-down menu.

 

Selection rules:

Control characters match label or name. They start at the first column of the label or name.

?        matches any character

*        matches any string of characters - must be last selection character.

A        matches A in the person label, and similarly all other characters except { }

{..}        braces characters which can match a single character: {ABC} matches A or B or C.

{.. - ..}        matches single characters in a range. {0-9} matches digits in the range 0 to 9.

{.. --..}        matches a single "-" {AB--} matches A or B or "-".

{~ABX}        omits person records which match A or B or X

 

Each ISELECT= performed using the "Specification" pull-down menu selects from all those analyzed. For incremental selections from the Specification menu, i.e., selecting from those already selected, specify +ISELECT=

 

Example 1:        Select for analysis only items with M in the 5th column of item name.

 

ISELECT=????M*        M in column means Math items

 

0001M 2x4        selected

0002R the cat        omitted

END NAMES

 

Example 2:        Select for analysis all items with code "A 4" in columns 2-4 of their names.

ISELECT="?A 4*"        quotes because a blank is included. A is in col. 2 etc.

ZA 4PQRS        selected

 

Example 3:        Select all Math (M in column 2) items which are Addition or Division (A or D in column 4):

ISELECT="?M?{AD}*"

1M3A456 2+2                selected

1M5D689 23/7                selected

1H2A123 George        omitted (History, American)

 

Example 3:        Select codes A, 1,2,3,4,5,6 in column 3:

ISELECT=??{A1-6}*

 

Example 4:        Select "- " in columns 2 and 3:

       ISELECT="?- "

 

Example 5:        Select "-" or "x" in column 2 with " " in column 3:

       ISELECT="?{--x} "

 

Example 6:Analyze only math (column 4 or person-id). Then report only items in Topic C (column 1). Then only report items in Strands 4 and 5 (column 2) in Topic C.

 

       ISELECT=???M*        in the Control file or at the Extra Specifications prompt.

       ISELECT=C*                using the Specification pull-down menu, after the analysis

       +ISELECT=?{45}*        using the Specification pull-down menu.

 

Example 7: 4 forms in one analysis with common items. Produce a score table for each form.

       In the item labels, columns 1-4 of item label are form indicator. Items can be in more than one form

       1xxx for form1 items

       12xx for form 1 and 2 items

       xx3x for form 3

       xx34 for form 3 and 4

       etc.

 

       Then, use the Specification menu box:

       ISELECT = 1??? will select all items on form 1

       Output Tables: Table 20 score table

       ISELECT = * select all items

       ISELECT = ?2?? will select all items on form 2

       etc.

 

Example 8: Omit unwanted items, marked by "x" in the first character of the item label:

       ISELECT={~x}

 

Example 9: If the field to be selected is already identified, then this simplifies counting the column:

@Dx = 16E17 ; $C44W2

16E17 means that the field is in columns 16 and 17 of the item label. Look at a data record to see what is actually there.

ISELECT=???????????????23        ; selects "23" in columns 16 and 17 of the item label


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