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<p class=MsoNormal>Hello <o:p></o:p></p>

<p class=MsoNormal>I have 2 versions of a test with 8 common items Test A
original and Test B secondary. (2 different cohorts of students) <o:p></o:p></p>

<p class=MsoNormal>When I anchor Test B with the common items from Test A and
run a Winsteps analysis the Mean measure of the items is -0.32 logits, an
easier test in the frame of reference of Test A if I am interpreting this
output correctly.<o:p></o:p></p>

<p class=MsoNormal>However, when I use MFORMS and compare the test
characteristic Curves of the two tests, the expected score for Test A at
ability 0 logits is 32.7 whereas the expected score for Test B at 0 Logits
ability is 27.26.<o:p></o:p></p>

<p class=MsoNormal>Am I correct in interpreting these results as suggesting
that although test C was a little easier than Test B, the student ability for
Test C was lower than Test B? <o:p></o:p></p>

<p class=MsoNormal>Basic question I realise but we are just beginning to use
Rasch tools to equate tests properly .<o:p></o:p></p>

<p class=MsoNormal>Many thanks<o:p></o:p></p>

<p class=MsoNormal><o:p>&nbsp;</o:p></p>

<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='font-size:8.0pt;font-family:"Arial","sans-serif";color:#4D4D4D'>IMOGENE
ROTHNIE</span></b><span style='font-size:8.0pt;font-family:"Arial","sans-serif";
color:#4D4D4D'>&nbsp;| Lecturer (Assessment) <br>
Office of Medical Education | Faculty of Medicine&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span><b><span
style='font-size:8.0pt'><o:p></o:p></span></b></p>

<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='font-size:8.0pt;font-family:"Arial","sans-serif";color:#4D4D4D'>THE
UNIVERSITY OF SYDNEY</span></b><span style='font-size:8.0pt;font-family:"Arial","sans-serif";
color:#4D4D4D'><br>
Rm 108, Edward Ford Bdg&nbsp; A27 | The University of Sydney | NSW | 2006&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <b><br>
T</b> +61 2 9036&nbsp;6434 &nbsp;| <b>F</b> +61 2 9036&nbsp;</span><span
style='font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333'>7580</span><span
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<b>M</b> +61 418 381 359 &nbsp;<br>
<b>E</b> </span><b><span style='font-size:8.0pt;font-family:"Arial","sans-serif"'><a
href="mailto:imogene.rothnie@sydney.edu.au"><span style='color:blue'>imogene.rothnie@sydney.edu.au</span></a></span></b><span
style='font-size:8.0pt;font-family:"Arial","sans-serif";color:#4D4D4D'>&nbsp; |
<b>W</b> </span><span style='font-size:8.0pt'><a href="http://sydney.edu.au"><b><span
style='font-family:"Arial","sans-serif";color:blue'>http://ome.med.usyd.edu.au</span></b></a></span><b><span
style='font-size:8.0pt;font-family:"Arial","sans-serif";color:#4D4D4D'> </span></b><span
style='font-size:8.0pt;font-family:"Arial","sans-serif";color:#4D4D4D'><o:p></o:p></span></p>

<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:8.0pt;font-family:"Arial","sans-serif";color:#4D4D4D'>CRICOS
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<p class=MsoNormal><span style='font-size:8.0pt;font-family:"Arial","sans-serif";
color:#4D4D4D'>Please think of our environment and only print this e-mail if
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<p class=MsoNormal><o:p>&nbsp;</o:p></p>

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