Author Topic: Displacement available in ConQuest?  (Read 578 times)

sukkeun

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Displacement available in ConQuest?
« on: July 17, 2012, 06:55:39 PM »
Hi
In Winsteps, if I use anchors, they provide displace category in item parameter estimates output.
According to their manual, "The DISPLACE value is the size of the change in the parameter estimate that would be observed in the next estimation iteration if this parameter was free (unanchored) and all other parameter estimates were anchored at their current values."

I used displace value to determine if I need to fix or free item parameters.

However, I can't find any information similar to displace in ConQuest.

Do you know if this value is available in ConQuest?

I am a novice with ConQuest so I may not know how to request it.
Any help would be appreciated.

ConQuest

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Re: Displacement available in ConQuest?
« Reply #1 on: July 24, 2012, 01:28:06 AM »
Sukkeun,

ConQuest does not provide this value directly, but here is a way to get it.

1. Do the estimation with the items anchored and save an item estimates file.
2. do a second run using the item estimates file as anchors, but omit the items that were previously anchored.  request just one interation in the estimate command.
3. The output from the second run will show how much shift in the originally anchored items would have been

if you'd like me to assist in setting up such a run please email me your files  conquest@acer.edu.au

Ray