CopyDetect_1.3 (2018-09-25)

  * The names of the functions 'CopyDetect1' and 'CopyDetect2' are replaced as 'similarity1' and 'similarity2'.

  * M4 index is added to the list of available response similarity indices
  
  * Instead of irtoys package, CopyDetect now relies on the mirt package for fitting various IRT models
  
  * As a result of using the mirt package, the package can also handle fitting the nominal response model. The user does not have to do this using another software and does not have to read the NRM item parameters into R. Package will handle everything.
  
  * Users have now flexibility of submitting a matrix including many pairs, so they can compute these indices for more than a single pair at one time.
  
  * Users have now flexibility of submitting a vector of center ids, assuming the data has a column indicating center IDs, to compute indices for all possible pairs in each test center.
  

CopyDetect_1.2 (2016-04-27)

  * A small computational adjustment for the S2 index is made

CopyDetect_1.1 (2014-08-06)

  * A small computational error for the S2 index is fixed

  * An adjustment in the omega index was made to avoid possible problem when missing data occurs in response vectors.
    Now, it can handle both scenarios: 
      1) Missing data in response vectors are read as "NA",
      2) Missing data in response vectors are read as system missing in R

  * An error was fixed for print.CopyDetect2 function, an internal function to be used for printing the CopyDetect2 objects. 
    Previously it could handle only five option items, now it can handle any number of options, and printing does not have any problems.
 
CopyDetect_1.0 (2012-10-02)

  * initial release on CRAN