<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;"><font face="arial" size="2">Hi Coty,</font><br><br><font face="arial" size="2">In ACT-R, a negative decay would imply a perfect memory (i.e., where the activation of instances increase over time). In my knowledge, there is only one paper that has found empirical (experimental) evidence of a negative decay value:</font><div style="font-family: arial; font-size: 10pt;"><br></div><div><font face="arial" size="2">http://act-r.psy.cmu.edu/papers/667/p1133.pdf </font><br><br>These authors tested it for an experiment involving arousal and recall. They found that a negative decay is better suited to model highly aroused individuals compared to low aroused individuals.<br><br><p class="MsoNormal" style="font-family: arial; font-size: 10pt;"></p><p class="MsoNormal" style="font-family: arial; font-size: 10pt;"></p><p class="yiv510711267MsoNormal"
style="font-family: arial, helvetica, clean, sans-serif; font-size: 13px; padding: 0px; line-height: 15.933333396911621px; outline: none; background-color: rgb(255, 255, 255);"></p><p class="MsoNormal" style="font-family: arial; font-size: 10pt;">Best,</p><p class="MsoNormal" style="font-family: arial; font-size: 10pt;">Varun</p><p class="MsoNormal" style="font-family: arial; font-size: 10pt;">--</p><p class="MsoNormal" style="font-family: arial; font-size: 10pt;">Varun Dutt, M.S., Ph.D.</p><p class="MsoNormal" style="font-family: arial; font-size: 10pt;">Co-advisor, International Relations</p><p class="MsoNormal" style="font-family: arial; font-size: 10pt;">Faculty Advisor,Undergraduate students</p><p class="MsoNormal" style="font-family: arial; font-size: 10pt;"><span style="font-size: 10pt;">Assistant Professor</span></p><p class="MsoNormal" style="font-family: arial; font-size: 10pt;">School of Computing and Electrical Engineering</p><p
class="MsoNormal" style="font-family: arial; font-size: 10pt;">School of Humanities and Social Sciences</p><p class="MsoNormal" style="font-family: arial; font-size: 10pt;">Indian Institute of Technology Mandi, India</p><p class="MsoNormal" style="font-family: arial; font-size: 10pt;"><br></p><font face="arial" size="2">--- On </font><b style="font-family: arial; font-size: 10pt;">Tue, 15/1/13, Cleotilde Gonzalez <i><coty@cmu.edu></i></b><font face="arial" size="2"> wrote:</font><br><blockquote style="font-family: arial; font-size: 10pt; border-left-width: 2px; border-left-style: solid; border-left-color: rgb(16, 16, 255); margin-left: 5px; padding-left: 5px;"><br>From: Cleotilde Gonzalez <coty@cmu.edu><br>Subject: [ACT-R-users] what does negative decay mean?<br>To: "act-r-users@act-r.psy.cmu.edu" <act-r-users@act-r.psy.cmu.edu><br>Date: Tuesday, 15 January, 2013, 19:35<br><br><div id="yiv2041714467">
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<p class="yiv2041714467MsoNormal"><span style="font-size:11.0pt;color:#1F497D;">ACT-R friends,</span></p>
<p class="yiv2041714467MsoNormal"><span style="font-size:11.0pt;color:#1F497D;"> During explorations of the decay parameter in the ACT-R activation equation, we have wondered if any body has ever used a negative value or even zero, or
even something different from the .5 default value. What would a negative value of decay mean? just curiosity, I don't think we are going to go that far :-)</span></p>
<p class="yiv2041714467MsoNormal"><span style="font-size:11.0pt;color:#1F497D;"> </span></p>
<p class="yiv2041714467MsoNormal"><span style="font-size:11.0pt;color:#1F497D;">Coty
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