Messages

16

Questions and Answers / Re: EAP/PV reliability estimates

« on: April 30, 2020, 04:54:29 AM »

I'm not sure I follow - you would have to upload a minimum working example so I could recreate it.
https://conquest-forums.acer.edu.au/index.php?topic=1239.0

17

ConQuest News / ACER ConQuest Version 5: available now!

« on: April 30, 2020, 04:51:55 AM »

Version 5 of ACER ConQuest is now available.

Version 5 is a major upgrade on version 4 and includes new features including:

• Bayesian estimation using Markov Chain Monte Carlo (MCMC)
• Integration with R through the conquestr library

You can download ConQuest 5 here: https://shop.acer.edu.au/acer-conquest-5

18

Questions and Answers / Re: standard error of conditional covariances/correlations in multidimensional run?

« on: April 27, 2020, 01:17:50 AM »

you can extract the full error variance-covariance matrix and include in your Show file. See here:

https://conquestmanual.netlify.app/s4-00.html#show

You need to:

1. use empirical errors

Code: [Select]

estimate ! ... stderr = empirical ...;This is the default behaviour if you do not specify the stderr option.
2. add the option to your show command

Code: [Select]

show ! ... tables = 10 ...; Table 10 is the error variance-covariance matrix

19

Questions and Answers / Re: EAP/PV reliability estimates

« on: April 17, 2020, 12:27:03 PM »

You are presumably using default scoring, such that your “lowest” response category is scored 1 (the lowest value of your code statement). You need a zero-scored response category, and you do that using a score statement:

Code: [Select]

score (1,2,3,4,5) (0,1,2,3,4);

See: https://conquestmanual.netlify.app/s4-00.html#score

20

Questions and Answers / Re: set directory

« on: December 19, 2019, 07:35:38 AM »

Do you just copy and paste the desired directory in there?

yes, you can copy and paste a path into the `set` command.

21

Questions and Answers / Re: set directory

« on: November 27, 2019, 10:43:44 AM »

ConQuest will set the working directory to the path where the executable was called from. This is normal and useful behaviour for command like tools. If you are using the GUI version, the working directory will be the location of the executable.

To change the working directory, you can use the `set` command:

Code: [Select]

set directory = “c:\user\”; will set the working directory to be the user folder on your drive mapped to the letter “c”. You can confirm this by printing the working directory:

Code: [Select]

dir;

22

Questions and Answers / Re: Release constrained parameter

« on: November 26, 2019, 12:55:53 AM »

No, the constraint of the last step parameter to be the negative sum of the rest is a necessary identification constraint for the model.

An easier way to interpret the rating scale or partial credit model you are estimating would be to look at the Thurstonian Thresholds (e.g., table 7 in the Show: `show ! tables = 1:2:3:4:7;`). In your example of it item scored 0, 1, 2, there will be 2 thresholds, labeled x.1 and x.2 (where x is your item numbers). Each threshold can be interpreted as the location on the latent trait at which the probability of achieving score >= 1 is > 0.5 (x.1) and score >=2 is 0.5 (x.2).

23

Questions and Answers / Re: Some mistakes. Help me.

« on: November 07, 2019, 11:21:09 PM »

can you provide some more information?

what sort of mistake/error are you encoutnering?

Can you provide a minimum working example? https://conquest-forums.acer.edu.au/index.php?topic=1239.0

Can you also not upload in proprietary formats (rar) - if you want to upload files, it is best to upload small, minimum working examples as text files.

24

Questions and Answers / Re: Asking about facet model with SPSS datafile

« on: September 06, 2019, 12:03:52 AM »

Hi Lan Anh,

You can specify a facet mode using an SPSS like this (based on your cqc file attached):

Code: [Select]

datafile  Obs.sav !
    filetype=spss, responses=A1 to C6, keeps = ObsID;

...


model item+step+item*step+ObsID;
This will give you a partial credit with a main effect for rater (ObsID) harshness. You will need to carefully think about model identification if you want to fit more complex models, like then in your attached cqc file - I don't think you will have an observation of every rater using every response category for every item in order to include the item*step*ObsID interaction.

25

Questions and Answers / Re: Multidimensional Within Item Partial Credit Model

« on: May 23, 2019, 12:22:32 AM »

check out:

Adams, R. J., Wilson, M., & Wang, W. (1997). The Multidimensional Random Coefficients Multinomial Logit Model. Applied Psychological Measurement, 21(1), 1–23. https://doi.org/10.1177/0146621697211001

26

Questions and Answers / Re: why ConQuest not use all cases in the .dat file?

« on: May 18, 2019, 03:07:40 AM »

This is a known bug in ConQuest:Version: 4.15.0.

There are two workaround:

1. remove pid form your format statement:

Code: [Select]

format responses 8-169 (a2);
2. Contact ACER sales to be issued a beta build of ACER ConQuest - see details in your earlier post https://conquest-forums.acer.edu.au/index.php?topic=1287.msg1640#msg1640

See attached your run from the beta build

27

Questions and Answers / Re: Tutorial files not available from the ACER shop

« on: April 26, 2019, 06:02:38 AM »

All the notes and tutorials can be downloaded from:

https://www.acer.org/au/conquest/notes-tutorials

I will follow up with the broken link on the shop page.

28

Questions and Answers / Small font size in ConQuest GUI on Windows 10

« on: April 23, 2019, 01:53:53 AM »

Some users have reported the font size in ConQuest GUI on Windows 10 is very small.

see example attached.

The workaround is to disable high DPI scaling behaviour.

1. Open ConQuest GUI
2. Right click the icon in the taskbar and click "properties"
3. Go to the Compatibility tab, enable “Override High DPI scaling behavior” and set the Scaling Behaviour to “System.”
4. click okay

See attached image.

29

Questions and Answers / Re: wle (or mle, eap) estimates using existing item parameters

« on: April 22, 2019, 08:34:23 AM »

by ".prn" files, do you mean exported item parameters, created using the "export" command?

https://conquestcommandref.netlify.com/commands.html#export

If so, yes, you can read in item parameters and use them as starting values or anchors using the "import" command. See:

https://conquestcommandref.netlify.com/commands.html#import

Remember that the item parameters exported are only those that are estimated. If you use the item constraint to identify your model, you're exported parameters will exclude the last item (which is the negative sum of the other items).

Another approach is to save the current state of conquest in a system file using the command "put". If you estimate a model, then write a system file, you can later read that system file back in and you won't need to re-estimate the model/calculate fit/gereate case estimates etc.

https://conquestcommandref.netlify.com/commands.html#put
https://conquestcommandref.netlify.com/commands.html#get

If you write a system file and also use R, you can read it into R using the conquestr library:

https://cran.r-project.org/package=conquestr

30

Questions and Answers / Re: Analysis contentwise result

« on: April 18, 2019, 01:34:35 AM »

One option would be to fit a multidimensional model.

See the Command Reference, the command is "score"

To fit multidimensional models, multiple score lists are provided. Here, the score statement has three score lists after the codes list, so the model that is fitted will be three-dimensional. Items 1 through 8 and item 12 are on dimension one; items 9, 13 through 16 and 18 are on dimension two; and items 10, 11 and 17 are on dimension three. Because each item is assigned to one dimension only (as indicated by the zeros in all but one of the score lists for each score statement), we call the model that will be fitted when the above score statements are used is a between-item multidimensional model.

Code: [Select]

score (1 2 3) (0 1 2) (0 0 0) (0 0 0) ! items (1-8,12);
score (1 2 3) (0 0 0) (0 1 2) (0 0 0) ! items (9,13-16,18);
score (1 2 3) (0 0 0) (0 0 0) (0 1 2) ! items (10,11,17);
https://conquestcommandref.netlify.com/commands.html#score

You will have to provide some more information - how many items in each sub-domain etc?

Uploading you data and syntax may also help.