Searching Web Databases by Structuring Keyword

Searching Web Databases by Structuring Keyword-Based Queries Pavel ´ Calado Altigran S. Silva Rodrigo C. Vieira Alberto H. F. Laender Berthier A. Ribeiro-Neto Department of Computer Science Federal University of Minas Gerais 31270-901 Belo Horizonte MG Brazil rcvieira, pavel, alti, laender, berthier
@dcc.ufmg.br ABSTRACT

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Categories and Subject Descriptors

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General Terms

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3.1 Definitions

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3.2 Querying the Target Database

3.3 The Prototype Web Search System

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4. RANKING STRUCTURED QUERIES

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a11

A11

a12

A12

Q21

Q3 and

Q31

a21

A1n1

A13

Q32

Q22

a1k1

a13

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a22

A21

Q42

a2k2 a2

a23

A22 A23

Or

A2n2 Or

A1

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P!ˆ!…8J ˆJƒ…‰R‹ZY

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Target Database

Unstructured Query

Query Structuring

Ranked Structured Queries

I ‰_‹KJƒ…UŒ
McŠ°Œ‡9…8W P OUP!ˆ!Œ †

:.R + >" a,9H'$ a"9Y!-(. b"9 F..89 Y >" , #.$ '98 1 / 3xN?F"9 5!. 7 %.H"c..8 P 5!.9 ,  !, cB  =.9,D"  + F" )6H, + >"9 bB  = 3 Ne"9 9 e)6T/.]5 =8  7W"9 D,9UH.'9. > I -  ! !E %, 'E2O ,  I3f¯:A"l9, 1 /  !- ! !E.` '98 > l" , H'$. .3W¯:A"9, > / <  !- ! !E:   [ / 3W¯W.H"9, Q /  !- ! !EFDB898 %,dV8 2MD'( cH9T& %,i3#¯:A"k9, Q / <  !-  ! Y"9 I-( @.W"9 IB8 8  !,@VE8 P 2 Q / "$U . !-(.$, 5+"9 P '98 1 < 3 : !A.  >  » $

, >  ¾  !- ! !E *-(. '9 cBHU a.x"9 F. '9 !Y.E!  !,d*" F9,  > » / $! , > / 7 !-( ! & !L2E3 0X ¾ %./" 9Td.1" #9 A?)6TXc, ! 9= 7xG.c 9BH. ! 7 D,9UH.'9. I.k'(E.T!7°)+ L"@ ' 8  ! 1 $

(  .9, 1 $ ( @3xNe#" ƒ%. 79, 1 »»  -  ! !E5» " : L 6.i+B.¾  !, '(E.T(7Y T&O ?NH71–;'(.: 7+)+"9  ["9 [  e6N O D -  ! !E %, 'E2d , > »» $,@" c  ?–;'(.: J a -  ! !E %,d'E2d9, > 3 N?nK   Jg." R7b9, Q  !- ! !EJ" kB8  8»e¾ %,DV8 2 Q ¾ $ 0 '   ( ?NH79–;'(:  ¾ 5 ( 0  ( ?ZY U  5
7 )+" R Q a"9 -9#    =MM"9 '    '98 7 Q ¾¾ " I-9b¾A» G  9=DD"  : '98 3 3 D, > ¾¾ "  A BZY U  3 C6" +    Le2*.RbB8 8  %,VE8 L 2 Q / )+ L"*"9 ;,9UH.'$  %.'( ; ! !D.W"9 ;- .'$.'  Le2*.R'   9= Q / 7&= & !"$U " ;,9H'$ o)1P'  & %,i7 *2µ Q /:H a¶A3W¯Q\ .   ="9 +  )P.TD []5 =8  E7 )P a%.>,  & b" b %VE8$U .R“ *2µ Q / H a ¶ $  *2µ Q / H >  » ( >  ¾ ¶  *µ  H >  »( >  ¾ ¶  *µ >  » ( >  ¾ ¶

    

 *µ    

 µ2Q / ¾ H >  ¾ ¶  » H >  » ¶ * *µ 1 » H >  » ¶  *µ 1 ¾ H >  ¾ ¶ *µ>  » ¶ *µ>  ¾ ¶ Bµ ~%¶ )+"    ;I9.   < ¶°=.  !ƒ"9 W..89 W."9 ; ”"a. .'  :."9 W& ! >  < .$, @ < 7 1"9 ”"J   [ < 3:C6"9 + %VE8$U .>=.8$HE ! ! "9 B89BP"9 ;BH !; P)+"  +"9 ;9L2D & ; A6 +"9.  " aVE89 R 2 Q /  bH.T !> E*!.9 , HU R3 C6" - .'$.'  Le2X1'    =>"9 * '98 1 / 75=.  !k" $

2Q

/

Query Processing

Ranked Objects

‡ … W5‰GˆŒW.ˆJƒ…UŒKY  Q $, ! %,*'E2%>  / 7& :, Ay$9 !,*.:F, #B8 9 ..R.9-' .'  L  !+ %A">-( '9 a89 b 1 / 7 ”3 3“ *µ 1W/:H >  / ¶ $¦'~ & ( < + 8 µB~ & *µ 1W/  / ¶¶ µ”m&¶ *» ) ) )+"9 A , / R" Q8 I'( i 8 !° F" :, H'$. QxU ' 8  1 / 3NP)P *!  , a"$U *µ 1 / < H >  / ¶¶ %.8 !b"9 c   U e2 '( e)6 ! !d"9 #..89 1W/ < .$,M" # Y $, %U %,['E 2 >  / 7(" ! ¯WV(3ƒµ”m&¶6 !Y8 ;"9%7$ Lx" a A1 +  >  / y9; \ .L2D"9 a..89 1 / < 75"9 Iy9$W-'9.'9  L?2k ~.3DNe1 .%7ƒ" Iy$9.W- .'$.'  Le2 )+ 9!!89c89  P."9 P-9 .    L  !:'( A?)6  !#" :  ,  >  / .$,D"9 b..89 1 / < 3 CƒJ, y99 a"9 c- '9.'  L?2dP.'9  9=>D..8 1 / < 7R=. & ! * ;.x A; 9, % !,M' 2 >  / K7 *µ 1 / < H >  / ¶A7 )6 F89 F" F! 9  %8  7°F, y99 %,MG.b" c& .-$. I, 5 k  G.U  X A :B2B !L'~ %’”3>C6" 89 1 / < .cU ' 8  1 / Y  !d.Y*& !;. H [ /H  !3PCƒ %.H">  @ 7  1W/ < )6 . =.Mb)6 ! =." - / 7 "$UP F9 !P" ; -(H.9 Yƒ"9 +  bU '98  1 / 79 >" F,9UH.'9. 79 ”3 3“ 848 - / 7 $ /| . . 0*0*112 2 4» »4363 5*+ 7 898 L. " @ 7 E)+! !8 +  1 / < µ E¶ )+"9 A; : 7 / "9 J89I'( A*.E!!8 !9! D  @ 7 K"9 ..89 !b"9 M '98 1W/ 7+$, , / "9 >H.;8 I'( I. ..89 !+FU ' 8  1 / 7( M" a,9H'$ 3 D. ! F"9;)6 c,  9x!.9 , x" PH, L .$i£g¬BI9. L'~ %’7&  ! :"  )6.89 ,-( !$  / 7 g3 3“ *µ 1 / < H >  / ¶ $f!.Uµ 1 / < ( >  / ¶ $>=@E ? 7BADC 8 - / 7 # - 7 µ >  / ¶ µv¶ = ? 7 ADC 8 /¾ 7 ]5 $ L2E7ƒ  ! I)P "$%& I /¡ $›H£”ž.›H£;-  G  !9 *.c2d A .; !7:¯WV(36µ”z&¶I, y$ !c" D-'9.'9  L?2O& .  >  / . !.9BH.E%“ *µ >  / ¶ $ GF ~C 8 F µ”z&¶ N?@89U2E7("9 *-'9.'9  L?. 2 *2µ Q /:H a¶b b"9 I!B B89   .(" 6 =. !B6    L  !:'( A?)6  !I"9 6 '98 1 8 !Q I"9 ,9UH.'9. 1$,b"9 : 8 !x =.9 %,a;" W -( ! & 6U '98   J" bB898 %,>VE8 2E3QC6"9 + 1H.9 U %,>'E2"9 b !V89 °“ *2µ Q /:H a¶ $ HIXL~ & ( < + µB~ &X%µ 1 » < ( >  » ¶¶eJ’  *» ) )  L'~ & ( µB~ &XUµ 1 ¾ < ( >  ¾ ¶¶e’ µr¶ < + »*) ) 

)+"  >  » $,,>  ¾  a"9 FBH Y)+"9 A c.9L2>" cVE8 2   A  9=[[U '98   1 » .$, 1 ¾ 7x !-(  & !L2E7xU J & 7 .$, U #" #H.x89c'( ;.:89 !;.F '98 ! 1 » , » $, 1 ¾ , J¾ " F,9UH.'9. 79.9I , HD.!8 1G.+"9 Y! BH.E' $T , *µ >  < ¶A3 0X %. %)}H9Tk.P"9 B8 8  !,/VE89   !#'E2X!.-98  = *2µ Q / H a¶*> %A"qF"9 !M3nC6" d89 D%`"9 !` ! ! .9 FVE8 2*;- E! !  =..9=a"9 Y.-JH9T& %, !!7.1" B2B !·!.M -9L2D- E !1"9 by9B;VE8 2E3 5.

  RANKING ! ;FB898 %,RETURNED VE89 2c P ! ! !,°7OBJECTS LP P8 '9 L %,cF" HU= ,9H'$ 3C6" > I.Y'B !c 8  %,/%.O"9 '( H9T& !,`.!.H,  =XX" M- .'$.'  Le2lF B_2  =/"9 M8    ! %,!3WCƒ#" P hi !A%7E"9 ;B898 %,V8 2$,*"9 + 89 %, .' ? !xU Q, ! %,b8   =6"9 WS6!2E ! # ?)P.TY, !."9%)+ @]5 =8 *m3FZYL"9.89="[" # ?)P.TM!.@'( c % 2d A\ -9.9, %, c, !iE2D,9H'$ bA" !7EG.; -9 ! L?2E7"  Y)P b"9%) .9L2d?)P[ '98 !!7 1 $, 1 3CƒJ -9 LG2d"9 * .HU .R7 )P a, y99 [ / 1"9  AY» Q.i ¾ !7 J"  8  %,' B !!7 "9;!.-( " F 8 !1 >"9 b,  >.x" F ' 8  1W/ 3 0f"9 !bH9T 9=6"9 5 A8 9 !,b' B !!7-( ! _ !E F ! %, ;'( P-9!2E %,; 8 : B!7& g3 37 '98 !ƒ"$UxU P!.9B L8  %, 'E2*a B1R..8 !!7.6 A\ -  . 9 %,* J•  Dm3~3WCRc \ !-  _2 " %)f"9 :e2-( Y5U ' 8  ; P % !,°7 D" Y ?)P.TI)P ; -    !EU '98  1 ¾ .;I..8 F BY ' 8  3 Q

And

QA 2

QA 1

a1

a 11

A11

a 12

A12

a 13

A13

a 1k1

a 21

A1n

a 22

A21

a2

a 2k2

a 23

A2k

A22

Or L 21

O1 Avg

I ‰G‹ ƒJ …UŒ
MNc‡@O(Œ=P%‰G‡$ ‰Gƒ‹ZY

O2 Avg

O3

Avg

L 22

On

L 23

L 2n

Avg

ƒŒˆ(Q#„$…8Ro†k„°ŽƒŒ‘‚„$…@…Œ=PJ5‘_ˆM…U‡$

RKX

NeM"9 a9 A?)6TM @]5 =.8  cm7i , L Q  !- ! !EY" #B8  8 %,>VE8 2E789'9 L %,;- E! !  = 3P¯:A"M , [Q 1 /  -    !EI"9 -$U*Y" JB8 8  %,VE8 2 Q¸ !  & J[" U '98  1W/ 3a¯W.H"d9, L > / <  !- ! !Eb ³ H  [ / 3#¯:A"  , 1 / <  !-  ! Y"9 a89 #.P" # '98 1 / d.' ? !  < 3Y•  ! # '98 1  BbU ' 8  79)6 #, ,M9 a  ! !:>" 9 e)6Ti3>¾ ¯W.H"9,   <  !- ! !EF"9  BI ..8 !* =.9 %,/M" JU '98  1 ¾ ¾ ' B / < 3@]5 $ L2E7 !.H"M9,  <  !- ! !E;c 89 %,D' B !%36ZY1'( G. 79)+ " !.H"l , D " J ?)P.T/ E!  %,ldH$, .^. '9 "9bHT& !" c..8 J~#J $, % I"9  @ !=&UH,  =k"9 D !-( ! & >9, D)1D.'9  %,° 3 W !. >  .$, >   -  ! !E@-( '9 MBHU >"9 JU .'9 !E! »  %,K)+ " ¾  , ! > » / .$, > ¾ / 7 !-( ! & 2E3

ZYK' B % < H. T& %,K.!!H, 9=/@"9 M-'9.'9  L?2l.  B_2  =O" [B898 %,fVE89 A2 Q*7+ g3 37Y" [- '9.'  L?2`. '   9=  < 7$=. & !>"9 Q )1.;'  & %,i7 *µ ».E!  !,n)+¾ L"o¾ %.H"n '98 @..8 @G.>" @y9$ - .'$'9  e2E3 0/ #, y$ a BFb, # ?899A .d.W L..89 !!3YC6"   7 "9 - '9.'  L?2DY" b BU '98  F += & >'E2i“ *µ  ¾ < H >  ¾ ¶ $Ã'~ & ( µB~ & *µ 1 ¾ 7H >  ¾ ¶¶ µ”u&¶

   $

2Q

1

7 A 

)+"9 A  ¦ " I b.: 9, \ !Y.F" c..8 !b @" I Bb !-  ! !E %,D'E 2  < 3W¯WV$3ƒµ”u¶6,  A  !6"$U%7.YI..8 b B+ '( F'  & %,i7 ¾; + !9.89=.">"$U+9 FQ L;..8 !1 Y.'9 & !,°3 ¯WV!32µ &¶.9,¦µ”u&¶ [" [= ! H.G.c89 k/H. T`X A 8  %,f' B %3ÂC6" k$, L .$F- '9.'  L  !M%o9%)j'( , Ay$9 !,°3#0/ IBHUa'E2["9 *-'$'9  L?2d.6'9 A  =J"9 I-$ .= Q  !  & #M.k ' 8  1 / 7ƒ=. & !d"$bJ b.P A!7 $, ! %,>'E 2 >  / 7 )6.+'  & %,i“ *µ2Q 1 /9H >  / ¶$  |~ L." " ! ; ($)+# 7 µ >  / ¶ $Ã~b h @ / 7 E!8 + P Q 1W/ µB~%|¶ )+"9 A # 7 µ >  / ¶; $, % !Y"9 # 8 cQ"9 ; ”"[. .'  c.W"9 & !A. >  / 7Y.9, @ / 7 D" ; ”"` As  [ / 3 C6" > %VE8$U  =89H  !1"$69L2"9 YBH !6)+"  b"9 Y 2D &    b"  Fx"9 FVE89 A! 2 QÃ)+ ƒ'( HT& !J E*9 , H °3 ZYG.[VE8 2KB898  = 71" [- '9.'  L?2`'    =/"9 ..89 1W/ < = & !b"9R"9 x ƒ 9, % !,b'2 >  / )6  :'  & %,i7 *µ 1 / < H >  / ¶A7Q I, y$ %,X8   =M"9 !.  J !.8  .3dC6"9 ..89 1W/ < $"9 P ' B !  < µg..89 1E!  %,I)+ L"I" 1 ' 8  1 / ¶ 1 ! !>.+a& !1. H [ / H  !3QC6" 6  7" %)6 !& A%7)P F E  !B %,/ O, A  9 9=M)+" "9 c %A"/  @ 7 E!!8 !7W 9%7$ >" F 8 1W/ < 36C6"9  A. .7$)6 #, Ay$9 b" b Â)6  =."E - / 7  -9L2J.!“ - / 7 $  |~ L "9@ 7 E)+! !8 +  1 / < µB~~%¶ C6"9 F-'9.'9  L?2J. 1 / < Y, y$ %,>!“ *µ 1 /  / ¶ $f!%µ 1 / < ( >  / ¶ $>= E ? 7 ADC 8 - / 7 # - 7 µ >  / ¶ µB'~ .¶ = ? 7DADC 8 /¾ 7 ZYR *• !   7. 9! W)6 P"9%& P ;-  A !9! :.x.E2a-$U A 89 U6 P.i !7¯WV$3(µB~%m¶:, Ay$9 W" ;-'9.'9  L?2E!  %, )+ L">"9 & ! >  / .;I!.9BH%“ *µ >  / ¶ $ F ~C 8 F µB~%m¶ N?k! !89 °7ƒ" *- .'$.'  Le0 2 *µ      L  !D'( ?)P ! !K"9 MU '98  > 8 ! `' B  
= & 89+"9 #VE8$ e2MW" FH.9T %,M Y.:. B)6 !7°Y)6 c, A ! !9,k9=D"9 #H.9T 9=L 3 Q !  .a|t{ a, Ay$9 !,@b"9 -  !  .I)+"9 c)6 :y$$,F"9 :y9B5 ! !..EQ.' ? !W c"9 WH. T& %, . B)6 6 %3xN?.8 P \-(   !E!7&"9 +-  !  .>$,I !!.(L 89 1%.J'(  ! !>.+! !  M !.8  1'( ?)P ! !J" Y !8 L ."9 M89.L2OB898 %,`VE8   !.9,K"9 MV8   !B89A 8  !,J'E2D8 ;=. L" M3 C5'9 X~>, H "9 JA"9H  B !." J !BD, H'$.  .9,FVE89   !!35C6"9 :V8   !R)P  WA"  !F+"$%& W1.&89c'(  .i)P.H, : 9! +0/ !'I89 W !$,ca8  ;" .PVE89   !!3x0X ; . "$Ub"9 #"9 =."k89c'( ;.: ! !Eb' B F-( aVE89 A2>F"9 U *,9H'$ D c, 8 *>"9  
6.

6.2 Results

RC *EXPERIMENTAL !..8$U b8;H9T 9=.1.xRESULTS B8 8  %,JVE89   !+$,J.  -(.$,  =. B)6 !7$)P a89 %,J" F -9 ! !E %,- .?2-( FB2B   #8 J A\ -( A  !3ƒ0/ Yy B+,  '( "9 b A\ -( A  H  A89-[$,D" !M, !891"9 Y !89L;.5" ! F \-(   !E!3

6.1 Experimental Setup

¯x\-(   !E()6  W-(  %,b89  =6"  ! W, B 9A5, H.'9. ! )+ L"-9-9 %U ., .. 9 57 /57E$,3   53.|bB8  8 %,I !BPVE89   !Q)6  ; %U %,I5P$,"/5W,9UH.'9. 7 $, &mDG.a"9     5F, H.'9. 3CƒM %A"kB898 %,kVE8 2 Q / µ.*,9UH.'$! )+ L"OA" !P  DFE1¶A7x)6 J. = %,O.89 B8 8  !,>VE89  2 N / 7$, y$ %,> <  021 < B8 8  %,@VE89 P 2 Q / )6.a89'  L %,>J" cH=.  , H'$. .3*C6" * 3  *CN / .P' B !Aa A8 9 !,°7i"9 A I%  %,k  b›š  šA­¡¤9¢Fž#© "Uš®¢g«H7R)1aHT& !k.b" * a.P!. c.9B)P  G." MVE89 G 2 N / 3lC6"9   8  %,O@ !..8$U >" U)Â.E2   b' B !Iµg ”3 37R' B !AF d b.:!. !A#.9B)P H¶;" B2B !} 1.'  ;F   !& Y)+" ! 2" Y8 9B8 8  %,VE8 2 N / ;- E ! %,°3 C6" P.B5!.9L289 %,a %.8 !RY, A  9 Q"9 :V89.L Le2O.FdH. T& %, .' B !A M- !!  f$, !% 1y9=. 8 !a U’”3:C6"9 ! F %8  !+U F, Ay$9 !,>.6G%)+!31]9;I= & ! VE8 2 N / 7(  *CN / '( a"9 a Y.W! !F.' ? !.$,M [  D 1 / '( F" aH.5 A:.' ? !; 8  %,>'E2J" aB2 B Áµg g3 37$" B2B !¸9B)P A¶A3 Q !  .[ Y, Ay$9 !,J!“ $

HD 1

 * /

CN /:H

H D 1W/9H

µB~%v¶

)+" A"/ F"9 #GH .P"9 * #1'B !Aa A & %,@"9a  . !%3:–; !%.° Y, y$ %,>!“ N / H  $ H D 1 H /*C N *C = µB~!z&¶ / H

)+" A"/ F"9 cGH.A ./.+. !#.'? !F"$UF)1.a   !& !,°3 GY8$ L2E7E)P U Y E  !B %,* "9 +..89 P.°- !!  H.T& !U ~.~BH.9,9UH,k !% :-( E!7x|tD7P~!|&tD 7 |&tD75m|tD7 &|tD7Wv|&tD7 z.|&tD7r.|&tT7 |tD7Eu.|&tD7E.$,~%|.|&tD3WC6" x- !!   U !%$!8 

C6"9 1 !BW)6  ;-( G. %,*'E2c89'9 L 9=Y"9 +89 B898 %, EV 89   !Q" 1B2 B  .$,c !8$  = “1µB~%¶5" 1B2B ! W!.-$U '9  L?2a9! !L2aB89A8  9=+"9 :VE89   !!7.9,µ
.¶°"9 :VE8$ Le2 µg-  !  .(¶6.x" H. T& %,J.9B)P !3 0q" !q.q8 9B8 8  %,`V8 2 N / J89'   !,°7+ J. H. T& %,bB8 8  %,V8   ! D Q / ° 8  %,°3ƒCƒ1 !..8$U :-(.  µB~U¶A7E" YB2B !   :%.-9.'9  L?2ƒ! !L2B89A8  9=F"9 ;89 A VE89   !!7°)6 I %.8 I"9 c8 I'( .6 '98 !F!. L2XB  = %,O[" JVE8   !I  D Q / 3/C5.'  ! ["9%)+I"9 -(  !E .=. 5! !+VE89 A 1.9,. !L2D =.9 %,D ' 8  ..89 -$ L+G.;"9 .-JH9T& %,D-( L  ;  D Q / 7 G.+"9 Y"  !  B ,9UH.'9. !!7     5aµ  ¶A7 / 5
µ 1¶+$, = 5aµ”S1¶A3 0/ # ! I"9bz|3 v.tD7xzvtD7R.9,Xr|&t¸.P" c" ="9 BbH. T& %, VE89   !R)6  :!. !A2aB8 8  !,°7 g3 .3 7.)6  : %VE8$&;" : = $;B8 8  !,lVE89 A2E7:G."9     57 /5.9, 5,  .  !7 !-( !A  !L2E3xNe()P 1!  _, W"9 6-*" ! 1-( L  P  "9 cH.9T 9=7R" *-( ! H= 6! !L2XB8 8  !,kVE89 A  L)1!2b.'(U& #rz&tD7(.$,>.;"9 ="duvt Y"  = 5Y,  . °3]9F"9 VE89 A bH.9T %,@ @"9 cy Ba-9 . *"9 IB2B ! )1W.'9 6Y!. !A2I, A  9 P" P! !W89 6?7UQ !.B%7 r &t}.R"9  '98 !!3 P  _,  9=I" Yy B6"  ! VE89   !1  B "9 DH. T  = 7 B 3~UtD7;\u 3 vt7;.$,Kuz3 rtw."9 >..8 !*)6  ! !L2M =9 !,>.;"9 Y"  ! F,  !3 C6"9  Y !8 P 9, %U Y"$U6"9 ;B2B ! 6!.-$'9 7BP. "9 c  .7ƒ1H.9T 9=J ky9Ba-  .! *" *!. *VE8 2E3Z; 7 'E2` - 2l"9%)+ 9=/" d89 "9 [y BD" ! @VE89   ! f"9 H. T  = 7E rz3 rtÃau&v.tÃ.("9 6  6" 189 Q)+ $'( +.'  1  ! !F" *! !a 3I¯W& @G.F"9 c.Q89I'( A6% ! )+"9 A [9.D;" >..89 !)+"  M! !L2f =9 !,°7;, 8 J 8 !89LH. T  =/-9- .H"R7+. > ! !..E' B !AJ ="E B Y'( > A8 9 !,°71)6 [, 89'( !%)F3o¯Q\-(   !EI)+ L" "9 3   5,9UH.'$ I"9U #" %)+k-(E b !8 . 9L2[,89 "9 !o E  ! . '( e)6 ! o" XU '98  k, .. 9!3 ]9 9BH9! 7R"9 #g.A#"9FE2[89 !F /U '98    4 : ./..8 !*D '98    6  @;T& >"9H, A*"9 DH.TO. , B 9=.89 "9  ='( ?)P ! !J" !M3 Cƒb  89 1"9 : !89L:= ! H %,c'2a" 1B898 %,IVE89 A  . I'9 %,D'E2"9 bB2B !M7)6 !- 8  %,DI, # ?89  M5"9  ' 8  !+ M %A"[VE8 2E7 ”3 37iE2J.' ? !Y!EH  9=U %B  YR" + 8 !P "9 YVE89 2c)1P 8  %,°35C6"9 .9B)P 6 A !.H 9!7U"9  A. .7&"9 x ! !..E%7%=. "9 R)+ L"F.E2   ! !..E:' B !!3WC6" P %)+68 WF !..89 1"9 1 hi  & !9  .#.8 D !89LDH.9T 9=O=. L" M7Y)+" H"q"9.89 ,f'( @.'  [ . =.dI"9 =" !B;!. FI"  ! !..E+' B !3 C6"9 Y=.H-9"9 !P J]5 =8 !  79v7$,Dz#" %)f"9 U H.=. -  A !  o>"9 d !B>VE89   !J q"  3   57 / 5D$, 5 ,9UH.'9. 7 !-( ! & 2E3WC6" !8&  '( ! %, ?]5 B: I"9%)+6"9 -  !  .#G.5" x !89L5.' H.  %,b)+"9 !F"9 Qy9B°H. T& %,aVE89 2

D8 I'(  Z6 '98 ! DY89c'(  F 2)6.H, –; ! !E .Q.'? ! -( AY.'? ! QVE89   ! -( AVE8 2 -( ;VE8 2 SPE.T ~!|&r7 |z m .| E3 mv ~&z3 r.v b ~.~%z7 )u m m .| E3 .v &m3 v.v ~.~%z7~.~%u z &m E3 mr ~%|7~%|z3 .m  U 
‡x‘GŒ M ƒ‡ …‡ Wˆ!Œ…‰ P!ˆ%‰ W:PD„$‚+ˆRŒkŽR‡9ˆ!‡5‡ P!Œ=P-J P!ŒŽl‰fˆƒŒ[Œ WŒ…‰g†kŒiˆP:Y –Y.9T 5. L . ~!B ~B [$, ~!B  9, ÃmH, FUH.'$  S  S  S    P. YV8   !aµt*¶ z.|3 v zv3 | r|3 | z&r3  |3 | &vE3 | r.z3 r &vE3 | u&vE3 | P. Y '98 !aµt*¶ r  3 | ~3 | r3 | r.z3 u3  u&vE3 v )3 ~ u E3 v uz3 r '
‡x‘GŒ L M ;Œ… W.Œ iˆ!‡ ‹$Œ[„$‚ W„$…U…UŒ W.ˆ%‘ O`‡ PP%‰G‹(ƒŒŽ S JƒŒ…‰G=Œ P*‡$5ŽK‡9ˆ!ˆ…. ‰ Jƒˆ!=Œ P:Y b..  

Results for Query Processing 1

User First

0.95 0.9 Precision

 D Q / Y89'9 L %,i3Q0/ F ! a"$U%7 G.Fƒ% !!7x~%|.|&tÂ.:. . !M. B)6 kµg ”3 37#~%|.|&tw !% _¶D d   !& %,i3 ]9J" 3   5, °7(" 8 ="[ L2[z|tÂ.Q"9 aVE89 A ;)P  c.  %71'(8  |&t^b"9 J' B !Al" J.-lb"9 DH.9T 9= U I ! !..E%7°)+"9 !Xv.|t¨.+Q" c ! !..EF.' ? !F)6 A I    ! %,°3+] .;"9 /5;.$. , = 5Y, .. M-  !  .d .L)1!2 '(U& #r.|tÂ)+" ![v|&t·.9,Mr|&tÂ.5" b ! !..E+' B !A;)P   A & %,°7 !-( !A  !L2E3 C6" Y8 & 1 .'(  !G , G : a"9%)+W"9 1 !89LW)+"9 !"9 +8     c" VE89 2dM'( -E! ! %,9=J"9 *"   *"9 =" !B H9T& !,DVE8   !6   D Q / 3Q–Y 89L1 YI8 A" - U& !,°3x] .6" 3   5b,. °7$"9 aB2B !{ Y9%) '9 aD" %) -  !  . 1'(8 #z.|&t{)+" !k.x"9 c  b' B !F)P  I   !& !,°3 ] .a"9 /5F, °75- !!   #.B~%|.|&t³" .89=."98 Y"9 MH9T& !,`. B)6 D %7;$,lG.D"90 = 5D, .. l" B2B !· Y.'  b" %)n" F89 Yu.|&t  ! !..E+' B !A!7$)+"9 ! r|&tÂ.x.R"  ! !..M.' ? !+)6  b   ! %,°3

0.85 0.8 0.75 0.7 0.65 0.6 0

10

20

30

40

50 60 Recall

70

80

90

100

Œ  Mb…Œ=W&‰ P%‰G„(…UŒ=W‡9‘‘J‡$‘ JRŒP‚„$…KˆƒŒn…ŒˆJR….RŒ Ž I ‰GK‹ Jƒ…U …UŒ=PJ5‘GˆP*‚„$… P:Y

Results for Query Processing 0.85

%U 6"$Q" ! 1%.I'( 6"9 =" L2I - U& !,#'E2#89 9=   G. >, H'$. *V8 2[=3*C6" ! I !8 L!7ƒ" U)P !& F * _ .1G8 8  b)P.T(3

User First

0.8 0.75

Precision

0.7 0.65

7. CONCLUSIONS AND FUTURE WORK

0.6 0.55 0.5 0.45 0.4 0.35 0.3 0

10

20

30

40

50

60

70

80

90

100

Recall

Œ ZMb…U=Œ W&‰ P%‰G„(…UŒW.‡$‘‘D ‡9‘ JƒŒ=P‚e„$…KˆƒŒn…UŒˆJƒ…ƒŒŽ I ‰G‹ Jƒ…U …UŒ=PJ5‘Gˆ P‚„$…¦„ƒ‰_ŒP:Y C6" ! [..89 ! 9, % M"9%71 ..9L2K8  89LH.9T 9= BHU !=.2@ %)+F"9 #B2B !¨D"9%)Ã" c8  F2J ! !..E .' ? !!7° !& [ W ..L)1!2"9 a! !bV8 2J YA"  !°7i'98 D"9%7$)+ L"@& 2J.589 Ab E H. .R7("9 #VE8$ e2M " 6 !89LQ%*'( 1"9 =" L2c   W"9 : !89Lx"$UW)P8 _,c'( .' H  %,'2.U)+  =I"9 ;89 Pc' 89  ,DaB89A8  %,DVE89 2E7& c89H"a. 6 .'( 89QH.T(35ZYL"9.89="#"9 P 89L5)6  1-(E  G.b"     5Y,  R7$. a-  !  $2> \-(   !E+ 9, L

N?*" W)P.T(7E)6 ;"$%& +-   !E %,b9U& !$.-9-&A"*#.%) "9 cVE89 2 9=:0X !'d,9UH.'$ !F89  =D8 9B8 8  %,[VE8   !!7 g3 375VE89 A !.9B L8  %,[.9L2[.PT& 2)6H, !3bC6"9 c.-9-&A"@  '$ %,l.`kS6!2E ! .l9 e)6T, !g7P)+" A"K!c'9 9 * ! L , 9! FH.T !MG.¨.' ? !FU '98  ;- U , aB89A8  F "9 T& A2)P.H,e'9. %,k89 cVE89 2E3[9! *" B898 %,/VE89 2 M,   9 %,i7+ LM >8 '9 L %,KO.9 @.J. @,9UH.'$ !!3 •  ! b"9 F 89 %,D BY.Q !8 ;%M'( #V8 L F \ !9 & 7)6 .J- -(. *DS6!2E ! .@9 A?)6T[, !RDH9T>" # !8 L .!.H,  =Ic" ! L;- '9.'  L?2D5 B_2  =*"9 b8    19 ! %,!3 8 ;VE8 2B898 9=$,D 89L+H.9T 9=c, !+- U , [GH. A)6.Tk.V8 2 9=[0/ !'O, H'$. *"$%“dµB~%¶I.%)+ "9 1G.I8   .RVE89 A :8   =#a 2I -  + E g! Iµg.9  9=. W \5 %UA"a'(%\9¶A7
µ ¶R %)+5" :8  :$1 9=. P E .! bVE8 2a.E2a89c'( 5(, hi A !EW,9H'$ !!7E$,µ”m&¶ƒ- U , ! "9 ; !89L+YaH. T& %, %7)+"9  " .' ? !+B1 T& !L2 . B)6 >"9 @89   [VE89 A2q k"9%)+oy9B%3·C6" ! /VE89. L  .T D.8 c- .-(.1 , %.PG.VE8 2  =M0/ !'/,9H'$ !*89H" .1" F9 Y%..  .'  F_·  FB. !+.Y, =. LH.ƒ ' HU  !!3 CƒD !Ba8a.- - &A"°7ƒ)P * -9 ! !E %,[D- .?2-( c0X !'

1

User First

0.95

Precision

0.9 0.85 0.8 0.75 0.7 0.65 0

10

20

30

40

50 60 Recall

70

L~A’ 

  ! "$#% & '( FS  - . %“:ZÕE2B !·]9 F A2)P.H,?SP. %,[• %H" & +–; !  9. bH.'9. !!39N?*  )H, ¤ +.-¢ /)H¤ ¢ešA›A¤$¡.¢g£”ž.¤$¡  0Wž.¤%%šA›šA¤(®HšIž.¤M´a¡.¢2¡ 16@¤ .£G¤iššA›A£G@¤ @µ•./ 3 7 6. L. 7 .|. | .¶A3  %’54 678 9!:; =&?@A "B@CEDF6>GH9!I56="cdede–Y !. 9=*'(8+Cƒ \8$°•    L?2  #0/ ' eS6. !,JN? >ZY!! ;•2B !M39¹;™¢ž.¤(žŸž.™« E¹ EšA¤9¢g«#¡¤(¬I¼d™  ¢g£gªg¹ EšA¤9¢6½ œ.«¢ešAŸcC« V&7R~*µB~%uu.u&¶A7$z&bv aTz3  zU5 ’ #%  f;"