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bias

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(barney knows (f.l.w.))

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fred 1001

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ÿ � ¿�ÀÃÁYÂÃÄ�Å{Æ¿AbÉeÆ�ÁYÁ3D

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Page 33: $0 $%12 ! 435 !6&7 #demo.cs.brandeis.edu/papers/levythesis.pdf · 2002-07-13 · a J p OQP } } @ } }

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Ü ÍHÝ Þ¢ß�ß^à^áSâ�Â~ã1ð�Ä�ä3Þ&åZÞ�ÂÁð^æ ¸`çLÞGæ�æÀeÀ s k z�q f n k qËY f$f WZY w�f�k W�Zm w\fZk WX[�x3to� k z\q f n cÀeÀ WZmZn kei ¼ f z k qz�q f [�x3qe½�mon cÀeÀ n\¼$ses k W f n�W�Y3qol k [�nPm$mPl�Æ k W�WZm3s$W k ly¼ w z�¿%z i z f ͽZY3qol k [hW�Y3qol k [ cÀeÀ ¿ZYZnPmÏÆ k W wPk [Zse¼ f z�qoÅX��Yon\� w3k lomonz�q f [�x3¿ZYZnPm cÀeÀ Æ i YPÅèn\¼$ses k W f z�q$Åèz�qolomPsZm3qolomPq f s k z�q f�wPk [os$¼ f Y f z k q À WZm f ¼$Weq¿ kek$i m$Y3qÏ[9x w3k [Zse¼ f mPl c

ÀoÁeÁÁ ÉPW�meY f monÏY3q ÂHÃoÄ � z f �ËY3We¿%z f WZY3W$Í�z�q�z f zPY iËw3k q$l9z f z k q9n�_�¼9n$z\q$ÅÁ WZm w�f YPq$Åe¼ i YPWËY3WeW�Y3Í k Æ � m�z\Åe� f n!uÎ] Ä z�[ k q^p�n�s$WZmPÆZm3W�m3q w m b �eW$WZYPÍÁ n\� k ¼ i l��ZY3t�mX}$×%�éW k3� nÏY3qol�Ö Á } wPkei ¼y[oq�n#_ � ��m3WZmX}�zyn f �ZmXqe¼y[o¿ZmPW k ÆÁ l9z�[9m3q�n$z k q9nÏYPq$l�Ö f �ZmXqe¼y[o¿�m3W k Æ f W�Y3q�nHÆ k WP[�n`uÁÁXÑ s�Y3WZYH[ � mZzHÅy� f n i z�q�meYPW�z\êZmPl Â\ÃZÄ � mZzHÅy� f nÁXÑ s�Y3WZYH[jq�W�mon kei ¼ f z k q�Æ k WËY fef W�Y w\fZk W wPk [os$¼ f Y f z k qÁÁPÀse¼e¿ i z w ÂHÃoÄ ]7l k ¼e¿ i m^ضÙvض٠� mZz\Åe� f n#_�z�q f q b {nH¼esZmPW!] b�cW�Y3q$l k [ g qZm � ½�Y3qol k [�] bLcz\q�z f z3Y i z\êZm#] � mZzHÅy� f n#_5q bLc�ÀoÁeÁÁ ÉPW�meY f monÏY3q ÂHÃoÄ � z f �ËY3We¿%z f WZY3W$Í�z�q�z f zPY iËw3k q$l9z f z k q9n�_�¼9n$z\q$Å k q�m�Ç\l9zB[�m3q�n$z k qZY iÁ Y3W$WZY3Í k Æ � mZzHÅy� f n`u�]��$q f � k q$Í^p�n�s$WZmPÆZm3W�m3q w m b Û9mZzHÅy� f nÏY3WZm i z�qZm$Y3W%z\êomylÁ ¿eÍ f YPë�z\q$Å�¼9nH¼ZY i WZm w�f Y3q$Åe¼ i Y3W � m�z\Åy� f nÏY3W$WZYPÍjYPq$l�WZm$YPl�z�q$Å f�k s fZk ¿ kPfefZk [v_Á i myÆ f�fZk W�zHÅy� f uÁÁXÑ s�Y3WZYH[ � mZzHÅy� f n i z�q�meYPW�z\êZmPl Â\ÃZÄ � mZzHÅy� f nÁXÑ s�Y3WZYH[jë�q$¼P[Z¿Zm3W k Æ ÂHÃoÄ f W�Y3q9n3Æ k WP[%nÁXÑ s�Y3WZYH[ËlÏq$¼P[Z¿Zm3W k Æ�l�zB[9mPq9noz k q�nÁXÑ s�Y3WZYH[jq�W�mon kei ¼ f z k q�Æ k WËY fef W�Y w\fZk W wPk [os$¼ f Y f z k q

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Ü ÍPìÁXÑ s�Y3WZYH[ínPmemyl�WZY3qol k [.nymemPlÁÁPÀse¼e¿ i z w ÂHÃoÄ ]7l k ¼e¿ i m^ض٠� mZzHÅy� f n#_�z�q f ë^_�z�q f l^_�z�q f q b {nH¼esZmPW!] b�cW�Y3q$l k [ g qZm � ½�Y3qol k [�] bLcz\q�z f z3Y i z\êZm#] � mZzHÅy� f n#_5ë^_�l^_5q b�c�ÀoÁeÁÁ ÉPW�meY f monÏY3q ÂHÃoÄ � z f ��z�q�z f zPY iËw3k q$l9z f z k q9nÎÆ�z�îZmyl�t�z3YXW�Y3q$l k [ínPm$mPl^_Á ¼9noz�q$Å�W�m w�f Y3qoÅy¼ i Y3WjY3W$WZY3Í k Æ � mZzHÅy� f n`u Ä memylËnH¼es$s k W f nÁ WZmPseW k ly¼ w z�¿%z i z f Í k Æ�W�mon\¼ i3f n`uÁÁXÑ s�Y3WZYH[ � mZzHÅy� f n i z�q�meYPW�z\êZmPl Â\ÃZÄ � mZzHÅy� f nÁXÑ s�Y3WZYH[jq�W�mon kei ¼ f z k q�Æ k WËY fef W�Y w\fZk W wPk [os$¼ f Y f z k qÁXÑ s�Y3WZYH[ínPmemyl�WZY3qol k [.nymemPlÁÁPÀse¼e¿ i z w ÂHÃoÄ ]7l k ¼e¿ i m^ضÙvض٠� mZz\Åe� f n#_�z�q f q�_ iek qoÅènPmemyl b {nH¼esZmPW!] b�cW�Y3q$l k [ g qZm � ½�Y3qol k [�]�nymemPl b�cz\q�z f z3Y i z\êZm#] � mZzHÅy� f n#_5q bLc�ÀoÁeÁÁ ÉPW�meY f monÏY3q ÂHÃoÄ � z f ��z�q�z f zPY iËw3k q$l9z f z k q9nÎÆ�z�îZmyl�t�z3YXW�Y3q$l k [ínPm$mPl^_Á ¼9noz�q$ÅjY k q�m�Ç\l9zB[�m3q�n$z k qZY i YPWeWZYPÍ k Æ � m�z\Åy� f n!uÁÁXÑ s�Y3WZYH[ � mZzHÅy� f n i z�q�meYPW�z\êZmPl Â\ÃZÄ � mZzHÅy� f nÁXÑ s�Y3WZYH[jë�q$¼P[Z¿Zm3W k Æ ÂHÃoÄ f W�Y3q9n3Æ k WP[%nÁXÑ s�Y3WZYH[ËlÏq$¼P[Z¿Zm3W k Æ�l�zB[9mPq9noz k q�nÁXÑ s�Y3WZYH[jq�W�mon kei ¼ f z k q�Æ k WËY fef W�Y w\fZk W wPk [os$¼ f Y f z k qÁXÑ s�Y3WZYH[ínPmemyl�WZY3qol k [.nymemPlÁÁPÀse¼e¿ i z w ÂHÃoÄ ]7l k ¼e¿ i m^ض٠� mZzHÅy� f n#_�z�q f ë^_�z�q f l^_�z�q f q�_ i$k qoÅËnymemyl b {nH¼esZmPW!] b�cW�Y3q$l k [ g qZm � ½�Y3qol k [�]�nymemPl b�cz\q�z f z3Y i z\êZm#] � mZzHÅy� f n#_5ë^_�l^_5q b�c�

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Ü ÍPï Þ¢ß�ß^à^áSâ�Â~ã1ð�Ä�ä3Þ&åZÞ�ÂÁð^æ ¸`çLÞGæ�æÀoÁeÁÁÎà z\q$ljY f$f WZY w�f�k W�s k z\q f n`u È ��zyn�[�m f � k l.zyn w Y iei mPljY3¼ fZk [9Y f z w Y iei ÍÏ¿$ÍÁ { Ñ i z�q$ëhðeÅom f � k z�q f nL] b Åom f � k z�q f nP�!_5¿$¼ f�w YPq�¿Zm w Y iei myl.z�q$lZm3s�m3q$lZm3q fZi Í fZkÁ n\¼$ses k W f�f z�[�z\q$Å�Æ k W k s f z�[�zHêoY f z k qvuÁÁPÀse¼e¿ i z w t k zHl�Æ�z�qole� k z�q f n�] b {

À$À n f YPW f z�q w mPq f m3W k Æèn\s�Y w m� k z�q f s g q�m � � k z\q f ] b�cÆ k Wñ]Rz\q f z g a!c z3ò\[�x3} c ×$×9z b {svu w3kek W$l1Ø7z\Ù g [9xPqe½ZmZn À � c�À$À [ k t�m f�k Y fef WZY w�fZk WÆ k W!]Bz�q f z g aóc zXò��e� c z\×e× b {z�q f ë gÏô Y f �1urY3¿�n�]7WZY3qol k [�uÚq�m3î f  q f ] b Ó3[�xPÖ b�c ÀeÀ WZYPq$l k [ f WZYPq9n3Æ k Wy[s gÏf ]�ë�_5s b�c�À$À Æ�z�qolÏs k z\q f n�¿eÍ�¿$WZmeYyl f �%Ç�Æ�z�W�n f nPm$Y3W w ���m w�f�k W�t$� k z\q f n g qZm � ��m w\fZk W�] bLc À$À s k z\q fhõ ¼�m3¼�m¾�Yon\� f YP¿ i mjnymem3q g qZm � ¾�YonH� f YP¿ i m#] bLc ÀeÀ ¾ZYZn\� Ä m f q kPf ÍZm f z\q ô Y f�i Y3¿¾�Yon\� f YP¿ i möض٠w Y w �Zm g q�m � ¾ZYZn\� f Y3¿ i möØ÷[�xPÖ$Ù c À$À s fùø Ç dXf WZY3q�nHÆ k WP[�]�s f bÆ k Wñ]Rz\q f ë g a!c ëZò\[�xPÖ c ×$×yë b w Y w �Zm^ØÚë$Ù g qZm � ¾�YonH� f YP¿ i m#] bLcto� k z\q f n`urYylel$ú i mH[9mPq f ]7s bLc À$À W kekPfjk Æ�Ò ÃoÄ nymeY3W w � f W�mem� ��z i m#]7t$� k z�q f n`uNn$zHêom#] b d a�b {

ÀeÀ Åom f s k z\q fs g ]N� k z�q f b to� k z�q f n`u�m i mH[9mPq f � f ] a9b�ct$� k z�q f n!uÚWZmH[ k tZmPú i mH[9m3q f � f ] a�b�c ÀeÀ f W�meY f n�t$� k z�q f n i z\ëZm�Y õ ¼�m3¼ZmÀeÀ We¼$q f �eW k ¼oÅy� f WZYPq9n3Æ k Wy[%nÆ k Wó]Bz�q f ë g a�c ë�ò\[9xyÖ c ×e×eë b {

� k z\q f�f s gÀeÀ z\Æ�s k z�q f z�q w Y w �Zm!_�¼9nPm w Y w ��mPl�tZY i ¼�mw Y w ��m^Ø ëoÙ�u w3k q f Y�z�q9n3ÖomPÍ!]�s b�û]7� k z\q f b w Y w �Zm�Ø ëoÙ�u¶ÅZm f ]�s býü

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Ü ÍyþÀeÀ k3f �ZmPW � zenPm w3k [os$¼ f m f WZY3q�nHÆ k WP[ k ÆÏs k z\q ff ]7ë^_5s bLc

À$À w Y w �ZmÎWZmZn\¼ iPfw Y w �Zm^ØÚë$ÙvuÚse¼ f ]7s^_ f s bLcÀ$À z\Æ f ��zen f WZYPq9n3Æ k Wy[ËÅ9z�t�monÏYXqZm � s k z\q f _�ë�mem3s f �ZmXqZm � s k z�q fzHÆó]�ÿ7nymemPqvu wPk q f YZz\q9n3Öom3Í�] f s beb { q f myÅom3W�ly¼y[e[ZÍ g q�m �  q f mPÅZm3W�] a9bLcnPm$m3q1uÚse¼ f ] f s^_�ly¼y[e[ZÍ b�ct$� k z\q f n!urYyleleú i mH[9m3q f ] f s bLc[9xPt$� k z�q f n!urYPl$leú i m\[�m3q f ] f s bLc�

��À$À Æ i YyÅ�Æ k W k q�m�Çyn\� kPf s k z\q f�w3k [ose¼ f Y f z k q[�x w3k [os$¼ f myl gÏf We¼�m c�

ÀoÁeÁÁ ½Zm f ¼eW$q9nÏY f$f W�Y w�f�k W�s k z�q f nÏYonÏ�3}ËY3W$WZYPÍvu à z�W9n f z�qet k ë�monÁ { Ñ i z�q$ëhðeÆ9z\q$l$� k z\q f n�] b Æ9z\q$l$� k z\q f nP�Ëz\Æ f ��Y f [9m f � k l��ZYZn�q k3f ¿Zm$m3q.z�q$t k ë�mPlÁ Y i WZmeYylyÍ1uÁÁXÑ W�m f ¼$Weq ô î$}�z�q f mPÅZm3WjY3WeW�Y3Í k Æ ô }%Ç\l9z�[9m3q�n$z k qZY i Y fef WZY w�fZk W�s k z\q f nÁPÀse¼e¿ i z w z\q f ØÚÙ1ØÚÙ�Åom f � k z�q f nL] b {

À$À nH¼es$s k W fËk qZm9ÇPnH� k3f s k z�q f.wPk [Zse¼ f Y f z k q�_�WZm f ¼eW$qzHÆ�]9ÿ�[�x w3k [os$¼ f myl b Æ9z\q$le� k z\q f nL] bLcz\q f ØÚÙ1ØÚÙ�s k z�q f n g q�m � z�q f Ø�[9xPt$� k z�q f n`uNn$zHêom#] b Ù1Ø÷[9xP}$Ù cÆ k Wñ]Rz\q f z g a!c z3ò\[�x3to� k z\q f n`u7noz\êZm#] bLc ×e×9z b {� k z�q f s g ]7� k z�q f b [�x3to� k z\q f n`urm i mH[9m3q f � f ]Rz b�cÆ k Wó]Bz�q fh»eg a�c » ò\[9xP} c ×e× » b {s k z\q f n�Ø7zHÙvØ » Ù g s1u w3k$k WolvØ » Ù c��W�m f ¼$Weq�s k z�q f n c�

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Ü ÍPº Þ¢ß�ß^à^áSâ�Â~ã1ð�Ä�ä3Þ&åZÞ�ÂÁð^æ ¸`çLÞGæ�æÀeÀ w3k [ose¼ f mÏÖ f � f WZYPq9n3Æ k Wy[ k Æ�s k z\q f �seW�z\tZY f mÏ� k z�q f�f ]Rz�q f ë�_�� k z\q f s b {

l k ¼e¿ i möØÚÙ�soÆ g qZm � l k ¼$¿ i m^Ø÷[�x3}oÙ c� k z�q f sZ� g qZm � � k z�q f ] bLcÀ$À q k Wy[9Y i z\êZm f�k ] a _B� b�� }Æ k Wñ]Rz\q f z g a!c z3ò\[�x3} c ×$×9z b {s$Æ1Ø7z\Ù g svu w3k$k W$l1Ø7zHÙ À ]7l k ¼$¿ i m b [�x3qe½�mon c�À$À [Z¼ iPf z�s i Í�¿eÍèn õ ¼ZYPWZm � m�z\Åy� f n�[9Y f W%z�îl k ¼e¿ i möØÚÙ�soÆo� g q�m � l k ¼e¿ i m^Ø�[9xP}$Ù c À$À z\q�z f z3Y i zHêomon f�k êZm3W kÆ k Wñ]Rz\q f z g a!c z3ò\[�x3} c ×$×9z b {Æ k Wó]Bz�q fh»eg a�c » ò\[9xP} c ×e× » b {soÆo��Ø7z\Ù�× g [�xPÆPÛ�Ø ëoÙvØ » ÙvØNz\Ù Á soÆvØ » Ù c��À$À Yylel�¿�zPYon�tZm w�f�k WÆ k Wñ]Rz\q f z g a!c z3ò\[�x3} c ×$×9z b {s$ÆZ�^Ø7zHÙ�× g [9xPÆeÒ1ØÚë$ÙvØNz\Ù c�À$À YPses i Í.n$zHÅ3[ k z\lÆ k Wñ]Rz\q f z g a!c z3ò\[�x3} c ×$×9z b {s$ÆZ�^Ø7zHÙ g noz\ÅP[ k zHl`]7s$Æo��Ø7zHÙ b�c�À$À l�zyn w WZm f zHêom fZk Ø���_~�$Ù � }Æ k Wñ]Rz\q f z g a!c z3ò\[�x3} c ×$×9z b {sZ�^u w3k$k WolvØ7zHÙ gÏô Y f �1u�[�z�q!]r[9xPqe½ZmZnjÇ���_Ï]Rz�q f b ]~[�x3q$½Zmon Á s$ÆZ�^ØNz\Ù b$b�c�W�m f ¼$Weq�sZ� c�

ÀeÀ n f Y3q$lZY3WolËnoz\ÅP[ k zHloY i n õ ¼ZYZn\�%z�q$Å�Æe¼eq w\f z k qseW�z\tZY f mÏl k ¼e¿ i mjn$z\ÅP[ k z\l`]Nl k ¼e¿ i m�î b {W�m f ¼$Weqñ]7l k ¼$¿ i m b ]�� À ]���× ô Y f �vurmPîes�]BÇ�î beb$b�c�

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iek q$ÅX[9YPî w3k lom g a!cÆ k Wó]Bz�q f z g a�c zPò3} c ×$×9z b {[�Y3î w3k lZmÎ× g ] iek q$Å b } Á [9x3¿�Yonym czHÆó]~[9YPî wPk lom d ] i$k q$Å b  q f myÅomPWvu ô ����x3�e�oÌ��Zú b ¿eW�meY3ë c�z\Æó]~[�Y3î w3k lZmÏò�] iek qoÅ b  q f mPÅZm3Wvu ô ���Zx3�$�$Ì��oú b ¿$WZmeYPë c[9xP¿ZYonym À g } c�

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Ü Ý#õ Þ¢ß�ß^à^áSâ�Â~ã1ð�Ä�ä3Þ&åZÞ�ÂÁð^æ ¸`çLÞGæ�æÀeÀ z�q%z f zPY i êomÏÆ k W�W�m w\f Y3qoÅy¼ i Y3W � m�z\Åe� f nseW�z\tZY f mXt k z\l.z�q%z f zPY i z\êom�]7l k ¼e¿ i m°ØÚÙ1ØÚÙ � _�z�q f q b {

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