************************************************** * * * Changes and Developments in the catR Package * * * ************************************************** ------------------------------------ - Changes in catR 2.5 (2013-02-07) - ------------------------------------ MINOR UPDATE o An error was debugged in the 'MWI' function. The selection of the information function values to compute the MLWI or MPWI was wrong, so that the same item was always selected, independently of the current response pattern (for the same set of administered items). Many thanks to Koken Ozaki (Institute of Statistical Mathematics, Tokyo, Japan) who noticed this problem. o Some typos were fixed. ------------------------------------ - Changes in catR 2.4 (2013-01-17) - ------------------------------------ MINOR UPDATE o An error was debugged in the 'createItemBank' function. When creating difficulty parameters with the 'unif' distribution, the selection of specified parameters was leading to an error. Many thanks to Przemek Lis and Michel Kosinski (Cambridge University, UK) who noticed this problem. o Some typos were fixed. ------------------------------------ - Changes in catR 2.3 (2012-05-09) - ------------------------------------ MINOR UPDATE o The references of several help files have been updated with respect to the formal publication of the related JSS paper about catR. o The CITATION file has been updated accordingly. ------------------------------------ - Changes in catR 2.2 (2012-03-15) - ------------------------------------ MINOR UPDATE o The references of several help files have been updated. o A basic NAMESPACE file has been added for compatibility with R versions 2.14.0 and later. ------------------------------------ - Changes in catR 2.1 (2011-12-05) - ------------------------------------ MINOR UPDATES o It is now possible to save the output of 'randomCAT' into a text file, by specifying the new arguments 'save.output' and 'output' properly. Similarly, the plots obtained with the 'plot.cat' function can be saved as PDF or JPEG files by specifying properly the new arguments 'save.plot' and 'save.options'. See the corresponding help files for further details. o Some typos have been fixed in the help files. ------------------------------------ - Changes in catR 2.0 (2011-10-21) - ------------------------------------ MAJOR UPDATES o Several distributions are now available for item parameter generation of the 'createItemBank' function. Possible distributions are: normal and uniform for item difficulties; normal, lognormal and uniform distributions for item discriminations; uniform and Beta for both item lower and upper asymptotes. o Item exposure control is now feasible with the so-called 'randomesque' approach (Kingsbury and Zara, 1989). The function 'nextItem' and 'randomCAT' hold now the 'randomesque' argument that sets the number of optimal items to be selected first, among those the next administered item will be randomly chosen. o Content balancing can now be controlled by specifying subgroups of items in the 'createItemBank' function. The subgroups are coded into a fifth column (after item parameters) and they are stored in the item bank by setting the new argument 'cb' (for "content balancing") to TRUE. If this fifth column is missing, or if 'cb' is set to FALSE (default), nothing changes from the previous version of catR. See also functions 'nextItem' and 'randomCAT', which were modified for content balancing, as well as the new function 'test.cbList' for testing the format of the 'cbControl' list of 'nextItem'. o Item parameters can now be provided as data frames in the 'createItemBank' function. This also permits to include subgroups of items easily. o As a consequence of the previous major update, many help files were updated for comptability with the new function 'createItemBank' (i.e. 'tcals' is no longer needed to be converted into a matrix). o The 'tcals' data set was updated by adding a fifth column, holding the subgroups of items as defined by the test. See the help file of 'tcals' for further details. o As a consequence of the previous major update, many help files were updated for compatibility of the new 'tcals' data set (i.e. all examples requiring the matrix of item parameters were slightly modified to remove the 'Group' variable). o The 'print.cat' function was updated to display output results of randomesque method for item expoisure control as well as for content balancing (whenever required). MINOR UPDATES o When the 'maxItems' criterion of 'randomCAT' is smaller than the 'stop$thr' argument, an error message is returned. Previously it contained a mistake, claiming that 'maxItems' is larger than 'stop$thr'. This has been fixed. o Some typos have been fixed in the help file of 'tcals' data set and 'nextItem' functin. ------------------------------------ - Changes in catR 1.6 (2011-04-11) - ------------------------------------ MINOR UPDATES o The 'Pi' functin has been slightly modified to avoid a technical bug: when probabilities Pi equal exactly zero or one, the ability estimates cannot be obtained with 'thetaEst' (the boundary conditions cannot be tested because of NaN values). Many thanks to Pan Tong (University of Texas MD Anderson Cancer Center, USA) who noticed this problem. ------------------------------------ - Changes in catR 1.5 (2010-10-28) - ------------------------------------ MINOR UPDATES o The help files of the 'thetaEst' and 'semTheta' methods have been updated as some information about the EAP estimation method was missing. ------------------------------------ - Changes in catR 1.4 (2010-10-17) - ------------------------------------ MINOR UPDATES o The method referred to Owen's rule for selecting items in the starting step and in the adaptative process, was renamed Urry's rule given that this simple method was suggested first by Urry (1970) and that Owen's Bayes procedure differs from this one. o Consequently to the point above, 'Owen' optional value of the 'itemSelect' argument of the 'test' list was replaced by 'Urry'. o In addition, the 'nextItem', 'testList', randomCAT' and 'print.cat' have been updated by the replacement of 'Owen' by 'Urry'. o A minor problem was fixed in the code of the 'randomCAT' function: the output list was not returning all the required elements (in particular, the value of the 'itemSelect' argument). o A minor issue was fixed in the 'print.cat' function: the output was not displayed correctly when only two items are selected at the initial step. ------------------------------------ - Changes in catR 1.3 (2010-10-08) - ------------------------------------ MINOR UPDATES o Several typos have been fixed. o The 'randomCAT' help file has been updated as some information was incorrect or incomplete. ------------------------------------ - Changes in catR 1.2 (2010-09-07) - ------------------------------------ MAJOR UPDATES o Several procedures for next item selection have been added. First, Maximum Likelihood Weighted Information (MLWI) and Maximum Posterior Weighted Information (MPWI) are now available. The command 'MWI' has been developed for that purpose. o Second, Maximum Expected Information (MEI) has been implemented for next item selection. The function 'MEI' was developed for computing MEI values. o The MEI criterion required the creation of the 'OIi' command for computing observed information function. o The Maximum Expected Posterior Variance (MEPV) is also available. The command 'EPV' computes expected posterior variances and is used within the 'nextItem' function. o Finally, the completely random selection of the next item is also possible right now. o The functions 'eapEst' and 'eapSem' have been modified to speed up their computation. The approximation of the integrals is now made by the 'integrate.xy' function from the package 'sfsmisc'. o The function 'startItems' has been modified. First, the argument 'bw' has been replaced by 'halfRange' and codes now for the half range of the sequence and not the full range (this was misleading). Second, the items can be selected either according to their difficulty level or their information function. This is specified by the 'startSelect' argument. o Consequently, the functions 'nextItem', 'testList', 'randomCAT' and 'print.cat' have been updated. MINOR UPDATES o The argument 'eapPar' from functions 'eapEst' and 'eapSem' has been renamed to 'parInt' for consistency with the 'MWI' and 'nextItem' functions. It better refers to the parameters for numerical integration and not only for the EAP method, but also for MLWI and MPWI computation. o Several typos have been fixed in the help manual. o The 'plot.cat' function has been modified. Now, the confidence intervals do not appear by default ('ci=FALSE' in the code). Moreover, confidence intervals are displayed with dotted traits, while the true ability level is drawn with a solid horizontal line. Also, any classification level can be specified and drawn by a dashed horizontal trait. ------------------------------------ - Changes in catR 1.1 (2010-06-15) - ------------------------------------ MAJOR UPDATES o Owen's procedure has been added as a method for next item selection. o Consequently, the functions 'nextItem', 'testList', 'randomCAT' and 'print.cat' have been updated. MINOR UPDATES o Several typos have been fixed in the help manual.