{
  "id": 1395,
  "title": "Prediction by Rasch model",
  "url": "/competitions/WhatDoYouKnow/discussion/1395",
  "author_name": "Mattia",
  "post_date": "2012-02-24T15:34:16.737000",
  "votes": 0,
  "comment_count": 0,
  "views": 2006,
  "content": "<p>Try&nbsp;</p>\r\n<p>P(Yij=1 | a*i,β*j) &nbsp;where &nbsp;P(.) i a two parameter Rasch model</p>\r\n<p>a) i is the i-th student</p>\r\n<p>b) j is the j-th parameter</p>\r\n<p>c) a*i, b*j are parameters estimated on the training set</p>\r\n<p>but...... don't forget to take account of the error variance in the estimation of the parameters</p>\r\n<p>I think also a random component at student level could help in order to catch possible tendency to guess (can be explained by time)</p>\r\n<p>Look at the litterature on regression with error in explanatory variables</p>\r\n<p>Hope can help</p>\r\n<p>Ceers</p>",
  "messages": [
    {
      "id": 8686,
      "postDate": "2012-02-24T15:34:16.737Z",
      "content": "<p>Try&nbsp;</p>\r\n<p>P(Yij=1 | a*i,β*j) &nbsp;where &nbsp;P(.) i a two parameter Rasch model</p>\r\n<p>a) i is the i-th student</p>\r\n<p>b) j is the j-th parameter</p>\r\n<p>c) a*i, b*j are parameters estimated on the training set</p>\r\n<p>but...... don't forget to take account of the error variance in the estimation of the parameters</p>\r\n<p>I think also a random component at student level could help in order to catch possible tendency to guess (can be explained by time)</p>\r\n<p>Look at the litterature on regression with error in explanatory variables</p>\r\n<p>Hope can help</p>\r\n<p>Ceers</p>"
    }
  ],
  "comments": [],
  "raw_markdown_by_id": {
    "8686": ""
  }
}