<div dir="ltr"><div class="gmail_default" style=""><div class="gmail_default" style=""><font color="#000000" face="georgia, serif" style=""><b style="">When:</b>         April 26th<b style=""> at <span style="background-color:rgb(255,255,0)">12:30pm CT  </span></b></font><div dir="ltr" style=""><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font color="#000000" face="georgia, serif"> <br><b>Where:</b><b>  </b>      Talk will be given<span style="background-color:rgb(255,255,0)"> </span><span style="background-color:rgb(255,255,0)"><font style="font-weight:bold"><u>live, in-person</u></font><font style="font-weight:bold"> </font></span>at</font></p><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font color="#000000" face="georgia, serif">                       TTIC, 6045 S. Kenwood Avenue</font></p><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font color="#000000" face="georgia, serif">                        5th Floor, Room 530<b>              </b>   </font></p><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font color="#000000" face="georgia, serif"><br></font></p><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font face="georgia, serif" color="#000000"><b><span class="gmail_default"></span>Virtually:</b>    via Panopto (<a href="https://uchicago.hosted.panopto.com/Panopto/Pages/Viewer.aspx?id=40c91295-4215-418a-962a-b067015cf4c1" target="_blank">Livestream</a>) </font></p><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font color="#000000" face="georgia, serif"> </font></p><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font face="georgia, serif"><font color="#000000"><b>Who:</b><b> </b>          </font>Siddharth Bhandari,<font color="#000000"> TTIC</font></font></p><table border="0" cellspacing="0" cellpadding="0" width="0" style="width:0in;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial;border-collapse:collapse"><tbody><tr><td style="padding:0in"></td></tr></tbody></table><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font color="#000000" face="georgia, serif"> <span class="gmail_default"></span></font></p><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font face="georgia, serif"><font color="#000000"><b>Title</b>:           </font>Median of differences is not difference of medians</font></p><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font face="georgia, serif" color="#000000"><br></font></p><div><font face="georgia, serif"><font color="#000000"><b>Abstract:</b>   </font>Average Treatment Effect (ATE) estimation is a well-studied problem in causal inference. However, it does not necessarily capture the heterogeneity in the data, and several approaches have been proposed to tackle the issue, including estimating the Quantile Treatment Effects. In the finite population setting containing n individuals, with treatment and control values denoted by the potential outcome vectors a,b, much of the prior work has focused on estimating median(a)− median(b). It is known that estimating the difference of medians is easier than the desired estimand of median(a−b), called the Median Treatment Effect (MTE). The fundamental problem of causal inference -- for every individual i, we can only observe one of the potential outcome values, i.e., either the value ai or bi, but not both, makes estimating the MTE particularly challenging.</font></div><font face="georgia, serif"><br>In this talk, we will see that the MTE is not estimable, and we will instead focus on a notion of quantile approximation of the MTE. We will prove lower bounds on the approximation factor and see an instance optimal efficient algorithm for approximating the MTE.<br><br>Based on joint work with Raghavendra Addanki at Adobe Research (2403.10618.pdf (<a href="http://arxiv.org">arxiv.org</a>)). <br></font><div><font face="georgia, serif"><br></font></div></div></div><div style=""><div class="gmail_default"><b><font color="#000000" face="georgia, serif">*********************************************************************************************</font></b></div><p class="MsoNormal" style="margin:0in 0in 8pt;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial;line-height:15.6933px"><font face="georgia, serif" color="#000000"><b>Masks are optional in all common areas. </b><b>Full visitor guidance is available at <a href="http://ttic.edu/visitors" target="_blank">ttic.edu/visitors</a>.</b></font></p><p class="MsoNormal" style="margin:0in 0in 12pt;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial;line-height:15.6933px"><b><font color="#000000" face="georgia, serif">*********************************************************************************************</font></b></p><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><b><i><font color="#000000" face="georgia, serif">Research at TTIC Seminar Series</font></i></b></p><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font color="#000000" face="georgia, serif"> </font></p><div class="gmail_default"><div dir="ltr"><div class="gmail_default"><div dir="ltr"><p class="MsoNormal" style="margin:0in;line-height:normal;background-image:initial;background-position:initial;background-size:initial;background-repeat:initial;background-origin:initial;background-clip:initial"><font face="georgia, serif" color="#000000">TTIC is hosting a weekly seminar series presenting the research currently underway at the Institute. Every week a different TTIC faculty member will present their research.  The lectures are intended for students seeking research topics and advisors and for the general TTIC and University of Chicago communities interested in hearing what their colleagues are up to.</font></p></div></div></div></div></div></div><div><font face="georgia, serif"><br></font></div><font face="georgia, serif"><span class="gmail_signature_prefix">-- </span><br></font><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><b style="background-color:rgb(255,255,255)"><font color="#3d85c6" face="georgia, serif">Brandie Jones </font></b><div><div><div><font face="georgia, serif"><font color="#3d85c6"><b><i>Executive </i></b></font><b style="color:rgb(61,133,198)"><i>Administrative Assistant</i></b></font></div></div><div><span style="background-color:rgb(255,255,255)"><font color="#3d85c6" face="georgia, serif">Toyota Technological Institute</font></span></div><div><span style="background-color:rgb(255,255,255)"><font color="#3d85c6" face="georgia, serif">6045 S. Kenwood Avenue</font></span></div><div><span style="background-color:rgb(255,255,255)"><font color="#3d85c6" face="georgia, serif">Chicago, IL  60637</font></span></div></div><div><span style="background-color:rgb(255,255,255)"><font color="#3d85c6" face="georgia, serif"><a href="http://www.ttic.edu" target="_blank">www.ttic.edu</a> </font></span></div></div></div></div>