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The Van Houten library has removed some of the personal information and all signatures from the approval page and biographical sketches of theses and dissertations in order to protect the identity of NJIT graduates and faculty. ABSTRACT

PROBLEMS RELATED TO EFFICACY MEASUREMENT AND ANALYSES

by Sibabrata Banerjee

In clinical research it is very common to compare two treatments on the basis of an efficacy vrbl Mr pfll f Χ nd Υ dnt th rpn f ptnt n th t trtnt A nd rptvl th ntt (Y (hh n b lld th prbblt ndx fr th Efft Sz f ntrt n lnl ttt h bjtv f th td t drv n ff r tht ld pr t trtnt r

nfrtvl nd bjtvl prd t th rlr pprh Krnl dnt

ttn fl nn-prtr thd tht h nt bn ll tlzd n ppld

tttl tl nl d t t pttnl plxt h rrnt td h tht th thd rbt vn ndr rrltn trtr tht r drn th pttn f

ll pbl dffrn h rnl thd n b ppld t th ttn f th OC

(vr Oprtn Chrtrt rv ll t th plnttn f nn- prtrz rrn f OC h r ndr th OC rv (AC hh xtl

l t th ntt (Y l xplrd n th drttn h thdl d fr th td t nrlz t thr r f ppltn OEMS EAE ΤΟ EICACY MEASUREMENT AND ANALYSES

by Sibabrata Banerjee

A Dissertation Submitted to the Faculty of New Jersey Institute of Technology in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Mathematical Sciences

Department of Mathematical Sciences

May 2007 Copyright © 2007 by Sibabrata Banerjee

ALL RIGHTS RESERVED APPROVAL PAGE

PROBLEMS RELATED TO EFFICACY MEASUREMENT AND ANALYSES

Sibabrata Baneriee

Dr. Sunil.K. War, Dissertation Advisor Date Associate Professor, Mathematical Sciences, NJIT

Dr. Mannish Bhattacharjee, Committee Member Date Professor Mathematical Sciences, NJIT

Dr. Farad Kianifard, Committee Member Date Senior Associate Director, Biometrics, Novartis Parma, NJ

Dr. Sandie Sin}iaray, Committee Member Date Research Scientist R&D, Educational Testing Service, NJ

Dr. Thomas Spencer I, Committee Member 'Date Professor, School of Management, Walden University, NJ

Dr. Kaushik Ghosth Committee Member Dte Assistant Professor, Mathematical Sciences, NJIT BIOGRAPHICAL SKETCH

Author: Sibabrata Banerjee

Degree: Doctor of Philosophy

Date: May 2007

Undergraduate and Graduate Education:

• Doctor of Philosophy in Mathematical Sciences, New Jersey Institute of Technology, Newark, NJ, 2007

• Master of Science in , Rniversity of Maryland, Baltimore, MD, 2003

• Master of Statistics, Indian Statistical Institute, Kolkata, India, 1997

• Bachelor of Statistics, Indian Statistical Institute, Kolkata, India, 1995

Major: Mathematical Sciences

Presentations and Publications:

Banerjee S. and Char, Sunil "Problems Related to Efficacy Measurement and Analysis" Joint Statistical Meeting (GSM) Seattle, Washington 2006

Banerjee S. and Boo, Wonsuk "A Comparison Study of Models for the Human Sex Ratio," Joint Statistical Meeting (JSM) Minneapolis, Minnesota, 2005

Banerjee S. and Roy Anindya, "Finite Sample of Local linear Estimation in EXPAR Models," Frontiers in Applied and Computational Mathematics (ACM) Conference, Newark, NJ 2004

iv Το blvd prnt t lvl f dr tr nd dr prnt n l

ν ACKNOWLEDGMENT

I ld l t xpr nr rttd t r Snl Chr h ntrdd t th prbl h l vn ntl d nd tn thn ld hv bn pbl tht h ntnt nrnt nd pprt It ld hv bn pbl t hv dn nthn tht r Mnnh htthrj n hlp l hd h dr pn I ld l nt h r th n prbl nd t th ltn r

trn hnt tht ld ld t th ltn r rd Knfrd drv pl thn h

n pprh trd lvn th prbl hn n n f h ppr h l vn

nbr f pntr nd d fr rrh nd h flld th r vr

ll Whtvr 1 hv nd t lrn bt th fl f rrh dnt tl fr h r h Spnr h dntd vrl fl b t n tht nd

ttt fr h prnl lltn M nr thn t h I ld l l t thn

r Snd Snhr fr h thnl dn fr t t t nr t

hl nd I vr frtnt t hv h n tt

r Kh Ght l nr n hl nd n prfr h hlpd nl th h t bth th thnl nd nn-thnl M

f hrr bn tttn hrlf hlpd th hr npt fr t t t

Alt vrthn tht I hv nd t lrn bt thnl prnttn d t hr

I l thnfl t th prtnt f Mthtl Sn nd th nvrt fr pprtn r nd fr th ptn nd thr flt vlbl t

vi AE O COES

Chptr

1 IOCIO 1

11 Objtv 1

1 rnd Infrtn

O-AAMEIC ESS 7

1 fnn th rbl 7

nt Ettn Mthd 15

3 Srvvl Anl 1

vr Oprtn Chrtrt Crv 1

3 AAMEIC ESS

31 Expnntl UMUE fr ES

3 Mnt Crl Sltn f th Ettr

KEE ESI ESIMAIO 7

1 Apprh 7

Ettn fr pndnt t 3

3 Sltn 3

5 ECEIE OEAIG CAACEISIC CE 51

51 n OC 51

5 OC fr nt 51

53 Ettn th rvtv f OC nd th AC n th nt 57

5 OC Mr f Eff 59

55 rl lt 3

vii TABLE OF CONTENTS (Continued) Chapter Page

COCSIOS A E SIES

AEI SOCE COES

EEECES 77

viii LIST OF TABLES

Table Page

1 trbtn f ld rr Chn r ln fr Anthprtnv r 9

Sr Sttt 1

3 Cvn l fr ffrnt t f Mn f Spl 1

31 lt fr Mnt Crl Sltn 5

1 Ch f Krnl 31

Effn f Krnl Cprd t Epnhnv Krnl 3

3- Cprn f nt Ett fr ffrnt Krnl n th S nddth f 15 11 nd 115 35

Cprn f Ettd Mn Intrtd Srd Errr f nt Cptd fr Indpndnt nd pndnt t

5 Ettd rbblt Gvn Aln th th Mn Srd Errr

Ettd rbblt Gvn Aln th 95% ttrp Cnfdn Intrvl nd Eprl rbblt 9

51 Efft Sz Mr fr ffrnt Mthd f Ettn

5 Cnfdn Intrvl f OC Crv 5

53 Ettd Optl hrhld l

ix LIST OF FIGURES

Figure Page

1 OC rv 1

1 Unvrt Krnl dnt tt f th fft f t blndd bld prr lrn dr vn ln th th rnl t th vltn pnt n bnddth 9

Unvrt Krnl dnt tt f th fft f t blndd bld prr lrn dr vn ln th th rnl t th vltn pnt n bnddth 9

3 nvrt Krnl dnt tt f th fft f t blndd bld prr lrn dr vn ln th th Epnhnv rnl t th vltn pnt n bnddth = nd 5 3

nvrt Krnl dnt tt f th fft f t blndd bld prr lrn dr vn ln th th Epnhnv rnl t th vltn pnt n bnddth = 9 nd 1 33

5 Unvrt Krnl dnt tt f th fft f t blndd bld prr lrn dr vn ln th th Epnhnv rnl t th vltn pnt n bnddth = 15 nd 3

nvrt Krnl dnt tt f th fft f t blndd bld prr lrn dr n vrl Krnl nd th bnddth 3

7 Mn ntrtd rd rrr (MISS prn f th dnt tt ptd fr n ndpndnt pl nd dpndnt pl 5

nt tt prd nt th tr dnt

9 nt tt fr vr lr nbr ( f ndpndnt brvtn 7

51 ndn th ptl pnt f drntn n th OC rv 5

5 Ar ndr th OC rv 57

53 h ptl thrhld vl 59

5 Eprl OC rv nd 95% nfdn bnd 3

χ CHAPTER 1

INTRODUCTION

1.1 Objective

h bjtv f th drttn t td r f efficacy. Strtn th th pf

prbl f prn t nt-hprtnv dr n dbl-blnd lnl trl

bootstrap kernel density estimate f th dffrn f th dr prpd h

bootstrap confidence intervals f th prpd dnt r l ptd h td

dntrt tht th thd frl rbt vn ndr dependent trtr tht r

drn th pttn f ll pbl dffrn n hh f th nfrn

bd A rv f th xtn thd f ff rnt h bn nldd

hhlhtn th lnt pnt nd lttn f h thd

h thd r l tlzd t td rvvl nl r pfll th

tt f th rvvl fntn nd th hzrd fntn A dnt bd lrth t

tt th drvtv f th rvr prtn hrtrt rv ntrdd n th

td An ppltn f th thd n drnnt nl xplrd hr

h drttn l tlz lrth h kernel density ttn nearest

neighbor ttn nd ROC regression nd h tht th n b fftvl dptd

ppld tttl tl n th r f phrtl ttt

In th ntxt f kernel density ttn bandwidth ltn thd pl

rl rl trtr rv f h thd r nldd n rnbl dtl All th

bnddth ltn thd fll ndr nrl l f prbl tht n b bd

ndr tht ptztn Stht ptztn rlt nd prbl r th b f

ll tttl thr

1 Expl f th ptztn nld maximum likelihood ttn likelihood ratio tt Neyman-Pearson Lemma nd ptztn f th bias nd th f n

ttr

.2 rnd Infrtn

Cprn t trtnt th rpt t prr ff vrbl prbl hh

nl nntrd n th lnl td Svrl prtr nd rprtrzd

thd r d t fnd ltn t th prbl rtr pprh r ftn bd

n nrlt ptn rprtrzd pprh r prrl rn bd tt l th Wilcoxon-Mann-Whitney(WMW) tt

Efft z (ES prnt th ntd f th dffrn btn t trtnt

ndr ndrtn In n f th rnt pprh ES prntd thtl

xprn nt l ndrtd b lnn An dl ES r ht t

pt nd ppl t bth lnn nd tttn An xpl f h r

vn b th prbblt ndx P (Y X) , hr nd dnt th prfrn

r f t ptn dr (n f hh b plb r t d tht th lrr th prfrn vl th r ff th dr

On f th frt td tht rvd th ttn f th ntt P (Y X)

Wlf nd (1971 h hv ndrd th ttn ndr th nrlt

ptn ll tht th ptn Cnfdn bnd fr P (Y X) nd

rltd ntt l xplrd th vrl xpl

Snff t l (19 hv xplrd th ntt P (Y X) nd rprtrzd vrn P (Y — P (X Y n trl dt n fr t ppltn In th ppr th hv ntrdd hbrd ttr th prtr ll rprtrzd 3 prprt h ttr ntll Wlxn-Mnn-Whtn (WMW ttt xpt th prprtn r lltd n nrlt ptn h hv l ntrdd n th ppr th ttr f P(Y>X) — (Y bd n nn-prtń dnt

ttn prdr h hv l hn bth th prl td nd thrtl jtftn b vrn ttn nd ptt rlt tht th hbrd ttr pseudo-MLE th ll t v rt rlt ndr n rtn t tht th

thd ttr bd n nn-prtń dnt ttn thd h bn d n

trl dt hr td v vdn tht th ttr pttll

vlnt t th MW ttt nd b rrtn thd nd bttrp trtnt

t vn r ttrtv (b rdd th ttr

Mthd bd n bttrp nfdn ntrvl f th ntt hv bn dd b Chn nd Knfrd ( It h bn rrtl pntd t b th tht th rjtn f th Wilcoxon-Mann-Whitney tt ld pl tht th t dtrbtn

ndrln th brvtn r nt th hrfr n n ff rnt

nl t n b rnbl nfrrd tht n trtnt bttr thn th thr vr th d nt prvd ntfbl r f ff Al t ntnd n th ppr

nd lltrtd th n xpl tht t nt rnbl t hft dl hn th rpn r trl h Wilcoxon-Mann-Whitney tt ftn d th hft

dl ptn

Cntrt prn btn vrl ES r hv bn dd b Atn

t l ( h hv ndrd th nl d `r f prtn btn t dtrbtn (Coven's d), n f th nnfl ES vr th lttn f th

'Coven 's d' l n t ptn f hdtt hh ftn nt th h

Odds ratio nd th generalized r l xplrd n th bv ntnd ppr 4

h ntt P (Y r th prbblt ndx ntrdd n f th pttv

ES r n th ppr b Atn t l (

Althh th prbblt ndx n bfr th l rltn btn th

eceie Oeaig Caaceisics (OC rv nd th ntt P (Y h

nrtd rnd ntrt n lnl rrh n ppr b Atn t l ( h

Keas τ l dd n th bv ppr bt th nl nnfl f th dt

lltd n thd pr rb t l ( hv l dvlpd thd f

nntn th prbblt ndx th th OC nd ntrdd th Aea ue e OC

Cue (AUC h t nvlvd prt f thr r n dtn fr vrt

Ause AC n ltrntv ndx fr th AUC hh ptd n th b f

-prtr rpn f th vrnt r hh r vn n dfflt prtl

ttn l nfndn fft AUC egessio l ntnd n th ntxt

h tp dvlpd n dtl b dd nd p (3 nd p (3

Aptt pprh trd th fft z r prbl r ndrd b

b ( l r bd thd f dtrnn ff th pr f thr Svrl pttv thd r dd nd fnl h rndd n th b f th prfrn prn f th thd n th bv ntnd ppr

OC npt brrd fr th nl dttn thr It n n th

ntxt f dl dnt ttn fr vltn f th prfrn f bnr

lfr th ntn tpt

hr frl xtnv ltrtr n ttn (Y hr Y fll t nnn dtrbtn nd G rptvl Whl th ntrt l n ttn th

ntt (Y prtvl n t pprh th prbl nd dr

nfrn t ndr th nt f th hft (= Y — f th rnd brvtn vtr nd Y r tlf rnd vrbl

prtr dnt ttn nvl thd hh h bn vrld fr

ln t b lnl tttn rtr dnt ttn hvr nl

d b tttn r xpl f nrl n ld nl hv t tt th

n (μ nd th vrn (σ fr th dt Altrntl f th dnt f th ntt

G n ld tr t tt th l nd th hp prtr α nd λ f th

dnt

nprtr dnt ttn nrl thd t dl th nnn dnt h thd r th nl ptn ptn f pf dnt r vn fl f dtrbtn (ltn l xpnntl fl t l rrd n th thd

h pprh n b ll dptd n th ntxt Intd f dln th th

ndvdl dnt f nd Y n n dl drtl th nd l t th bv

ntnd ntt th flln

In th rrnt td nprtr dnt ttn thd r ppld fr

ttn th ntt 00 . Aln th t tt f ( v btnd fr n thrhld vl v Mr n th ld b vn n th dnt ttn hptr

Aprt fr th nprtr dnt ttn prtr pprh l hv

rt ptntl f xplrd n prbl pf dln r xpl xpnntl ό dbl xpnntl nfr r nrlzd nfr ptn ld t th

rrpndn Uiomy Miimum aiace Uiase Esimae (UMUE f PAY

nd nfrn rltd t t (Al t l 5 CHAPTER

NON-PARAMETRIC RESULTS

In th hptr th rnl prbl th td f t nthprtnv dr ll b drbd n dtl h rlvn f th nnrprtr dnt ttn thd nd thr ppltn t th prbl ll l b pntd t ffrnt dnt ttn

thd ll b ndrd th th prbl n th frrnd Srvvl nl

thd nd rvr prtn hrtrt rv r vr ll rltd t

nnrprtr dnt ttn nl b th lrth tht r fr

ttn th dnt ptntll hlp t p th tt f hzrd fntn

(flr rt nd rvr prtn hrtrt rv

2.1 Defining the Problem

h flln dt (bl 1 n dblrblnd lnl trl t pr t

nthprtnv dr btnd fr t l (199 nd Chn nd Knfrd

( h prr ff vrbl th hn n bld prr fr th bln

dffrn f th bld prr rdn ftr th trtnt th th dr fr th

bld prr rdn bfr th trtnt Mt f th nl n th nd f prbl

thr nrlt nd nvlv n unpaired trtt r th nl ptn

nnrprtr vrn f th t-tt nl th WlxnrMnnrWhtn (MW

tt (l lld th MnnrWhtn U tt

h MW tt r rn bd tt lld th Wlxn rn- tt nd th

MnnrWhtn U tt ntrdd ndpndntl b Wlxn (195 nd Mnn nd

Whtn (197 h prp f th tt fndn t f th t rnd vrbl h

th dtrbtn r f n f th rnd vrbl thtll lrr thn th 7 8 thr tld dn f th tt ln th lr rn bd tt r nldd

n hnn (199 S f th td bn th t tt th Wlxn-Mnn-

Whtn (MW tt vr th MW tt ftn d hr t ppltn dtrbtn r d t hv th nrl hp bt n f th hftd rltv t th thr b ntnt nt Δ ndr th ltrntv hpth h

pttnl pt f th WMW tt ttt hv bn rvd b n rrhr rnhrd t l (19 nd dbr (1995 hv xnd th r f th MW tt n rptr tttl p rnn t l ( hv rvd th prfrn f th MW tt th 11 rl tttl p

h hv d rl dtt fr phrll xprnt nd fnd tht th

rl tttl p v vr dffrnt t fr th Wlxn-Mnn-

Whtn tt h pplr n n thr lt f 11 p nld SAS 1 Srpl

SASS IMA 35 nd SYSA 9

In Chn nd Knfrd ( th hv ndrd th ff r 00

vn b bl 2. trbtn f ld rr Chn fr ln fr Anthprtnv r [Sr Chn nd Κnfrd ( t l (199]

h dtt vn n bl 1 ll b rptdl d n th prnt td A

r ttt f th dtt nldd n th bl t v rh d f th dt tht th rdr ld b prprd fr th dffrnt nl prfrd t ltr pnt n th td 0

bl 2.2 Sr Sttt

It h bn pntd t n Chn nd Knfrd A tht PAY

vlnt t th WicooMau n-Wiey ttt n ntn dt Α oosa coiece iea fr th bv prtr Γο h bn ptd n th ppr It h

l bn ntnd thr tht th BMW ttt d nt v ntfbl r

f ff Gnrll pn ln t th rtl vl f th Mnn-Whtn r

ttt r drvn nfdn ntrvl f th bv ntnd prtr Γο ld

v th h ndd nht f th ff It ld l t lr t f th

dn f th t dtrbtn n tn r nfntl dffrnt ndr th hft

dl ptn h nfrtn tht t ld fl t prvd ld l b vtl r

xpl t ld nt b bl t v nfrtn n th ndrln nrtnt f th t dtrbtn r ntfbl dffrn f th n f th t dtrbtn

Std h tht th Mnn-WhtnrU ttt n b nrlbl f th vrn f th t ppltn r t dffrnt It l h th drb f nrn n nfrtn

btnbl fr th ndrln dtrbtn; S Snff A19 On t l A19 r

rnb nd MCrt A195 tthff A193 h ntrdd dfd fr f th

Wlxn ttt t tt brdr fr f nll hpth tht nvlv nl vrn

nd bn f nrlt hh nl rfrrd t th hrnrhr prbl

Coe s nnrprtr r f fft z nl d n phtr nd thr r f ppld ttt nd prtlrl n prbl tht hv

lr trtr th n td bv It vn b th flln frl

hr Y nd r th rptv n nd Sp th pld tndrd

dvtn Sl nd S2 r th tndrd dvtn f th t pl f z i & 2 rptvl h dvnt f rn th th r tht t nt bd n dtrbtnl ptn nd nt fr t r fr nnrtttn t

ndrtnd th fft z jt b ln t th prrbd lt fr xpl fr

ll fft z 5 fr drt nd fr hh fft z (Atn t l h lt nnt b tttll nnfl

vr t t h tht th nl vrn `Cvn d nt

nnfl ttr f fft z It t pt th r nd hv Chn d vl llr thn nd t hv t prtd pr f ppltn r xpl

n th flln r ttt th `Cvn d llr thn th prrbd bt th n r fr prt 2

bl 2. `Cvn d l fr ffrnt t f Mn f Spl

h `Cvn d vl vn b 19 ( nd t n n rdl tht th fft z hld b fr r thn drt Gvn n bl 3 r th `Cvn d vl fr dffrnt rt f th n pn th rnn rltn th prnt xpl

t vn ll fft z th n f n pl h t b t lt bt 5 t br thn th thr h tndrd dvtn f n pl bn 3 t br thn th thr pl rl n xplnn th lvl f th fft z

Cndr th prr ff vrbl f th t dr n tn In th t

th hn n bld-prr ftr dntrn th dr t tht th pr f vrbl fr t dffrnt dtrbtn dfnd n th dn bt pbl th dffrnt vrn hp nd trtr ht th prbblt dnt f bth th vrbl ld hv ll th ptv n th bt f th rl ln

Addtnll th r ndpndnt f n nthr h tt f lt f n ndr th nrl ptn f nl vrn t nvlvd hn nrlt nt

d; th rfrrd t th BevrensrFisveru Problem.

Evn f t nn tht th n r th dn f n trtnt br thn th

thr n ld tll b nr f th nr t th tn "h h br ?" h

tn th f fr th r f fft z Cndr t pl fr t dffrnt ppltn h brvtn fr th t ppltn r ndpndnt f

n nthr bth thn nd btn th pl If th td n thd pr n

n dfn t b th vtr f pr dffrn h ttn n dl th pr

f ndpndnt pl nd ddtnll th nt b f th z lthh n th xpl th pl z r th If n ld l t th vtr f ll pbl dffrn th r dr fr th dtrbtn f th tr dffrn t tht th r dntll dtrbtd th thrtl dtrbtn f th dffrn bt th r nt ndpndnt th hrt f th dffrn vl ld b rrltd th

h thr h dnt ptd fr th dffrn n th vtr ld nt nl prvd th hp f th dffrn t ld l prvd tt f th nd

thr quintiles, nd th variance nd n b tlzd t t th tt f th drvtv f th dnt It ld l v lr d f th nt f prtn f th t dtrbtn Appltn f bootstrap prdr hlp n th rvl f b At th pnt t hld b ntd tht MW ttt tlf ptd n tht

ntrd th hrt f dpndn nd t th rlt nbd t n b

hn tht t bln t lrr l f tr ttt nl th ttt

Gvn pr f vtr f brvd vl fr th t dtrbtn n n l t th dffrn fr ll pbl bntn h th dffrn dntd b AY - Χ hh th bbrvtn fr nx1 = A 1 mη hr Υ nd X r

t vtr f dnn n x 1 nd x 1 rptvl nd = Υ — Χ 4 . Ma- Wiey U n nbd ttr fr th prtr Θ hh dfnd

r ntn dtrbtn t rd t

t tht th dfntn f fr th nn-nt dtrbtn nvlv th

ddtnl tr 1 AY = h tr ntrdd t djt fr t n th pl

vr th ddd tr 1 AY = nr tht th nfrtn f t d nd

ntnt th th xprn f nrntl prbblt vn b th flln

xprn

h eceie Oeaig Caaceisic rv ppld n th ntxt f ff

rnt l nthr ppln r f td r b f th rltnhp

f th r ndr th rv nd th flln ntt P AY th prbblt

r f fft z

2.2 nt Ettn Mthd

An tht th dtrbtn h ntn drvtv dnt ttn prdr

n b ppld th nl ptn t th dnt f D xt h dnt

ttn prdr hlp n vlzn th prtn btn th t trtnt dtrbtn h tt ptr th hp f th tr dnt 15 nt n b ptd n vr nn-prtr thd h vistogram, kernel , maximum penalized likelivood estimation, th nearest neigvbor metvod t l Krnl thd n b bd n vrl dffrnt rnl

th ntrtn prprt f th nddt rnl Adptv nd vrbl rnl

thd r pplr n dffrnt tttl ppltn

Aprt fr th h f rnl thr r vrl thd f h f bnddth n kernel density estimation. vr dffrnt bntn f h f bnddth nd rnl ld t ttd dnt th dffrnt hp nd prprt

ftn nhrtd fr th rnl d fr ttn In ddtn dpndn pn th

h f pnlt fntn ltn f rnl nd bnddth n b fftd

rtntl th ttn prdr rltvl nntv t th h f rnl bt

ntv t th h f bnddth

h t pplr thd f ttn dnt th htr thd

Althh th thd nttv nd t fll nd prhp th t dl

ptd n hvr t ffr fr r drb h t prtnt

n th hp f th dnt hh n dpnd hvl n th hn bin-widtv nd th nbr f bn Al th htr jt lltn f bx td vr n

nthr rprntn th frn r th rltv frn f th bn vr th trt dnt b bltl ntn nd hv drvtv f n r ll

rdr h htr dnt tt nt ptr fndntl pt f th ndrln trtr h vr hftd htr AAS d rtf t f th prbl nntrd b th rdnr htr pprh S Slvrn A19 r Stt

A199 fr dtld dn

h rnl dnt tt n th thr hnd dpnd n th h f rnl

nd th bnddth h ndrln hp f th dnt tt d nt hn h 6 th rnbl h f bnddth vr th dr th bnddth th thr

ll b th hp f th dnt ll bnddth h n vrl rh rv nd t d bnddth n th t th prtnt dtl fr th hp f th dnt

3 Srvvl Anl

Hazard rate o nl d n rvvl nl It dfnd

hr fAt) is th dnt fntn nd FAt) is th ltv dtrbtn fntn t tht f th rnd vrbl Y nd hv prprtnl vazard rates, nd th ntnt f prprtnlt tht f th flln rltn hld

h nnrprtr prprt vr lr prprt hld ndr r

ndtn hh d nt th dnt

n n nfrn bd n th prprtnlt ntnt n ft drtl

ntrprtbl nfrn n P AY Extn rlblt tt l l-rn tt hv bn dvlpd t dr nfrn n th ntnt f prprtnlt

2.4 vr Oprtn Chrtrt Crv

vr Oprtn Chrtrt AOC rv brrd fr th nl dttn thr vr ll rltd t th ES Α pnt n th OC rv n b xprd

Whr Y c ndt lftn nt th l f

r ° nd ι dnt dd nd hlth ppltn rptvl S dd nd

p A3 fr prhnv dn n th h rv ntrtd b jnn dffrnt pnt bd n drn thrhld c, lthh th xt vl f c nt rprntd n th rv dfntn th rn f th rv [ 1] x [ 1] r th 1 pnt f v f OC rv n th ntxt f ES ld dnt PAYE c 1

Ρ(Χ c) ht brvtn rnll fr th l r dntd Χ

h prl ROC rv n b btnd fr pr f dt vtr pl b plttn th prl rvvl fntn f th t rnd vrbl n th

prl ROC rv t dffrnt hp bd n dffrnt pl brvtn

Expl f ROC rv th lltrtn r nldd n th ltn tn Gvn

n r 1 plt f OC rv f t ppltn dd nd nrl hr th hrzntl x rprnt th nrl ppltn

r 1 OC rv

Mthd lr t th n d n nn-prtr dnt ttn n b

ppld t tt th thrtl hp f th ROC rv Althh thr n

nrn pplrt f th f th ROC rv n fld l rdl nd lnl

ttt nt n rrhr hv xplrd th dnt ttn pprh n th

ntxt

Area under tve ROC curve (AUROC), th n t th ntt

btnd b rn th r ndr th ROC rv It l hd tht AUROC thrtll l t th ES. n n nfrn bd n AUROC xtl vlnt t tht bd n ES.

Ett fr th ES l b btnd b th drt pprh h n t b n

f th prr f f th pprh f th td CAE

AAMEIC ESUS

nprtr d hlp hn n prtr ptn t b tftr r

vn vld t n th prn f nn dtrbtn th rtn nnn prtr

t pbl t fnd UMU f th ES h prbl lvd xtl th

n ld lv UMU prbl n th prtr t p Al t l (5 hv

ttptd t lv th prbl ndr th ptn f Gnrlzd Unfr dtrbtn nd fll fnd UMUE tt f 8= P (Y nd l f

= (Y } hr Γ lld th rlblt r h hv dd

xpl f tttl tlrn n th ntxt f dtr f brn nd hft

Gnrlzd Unfr ld b d h n th ntxt bt n lnl

ff nd rltd ppltn th xpnntl fl f dtrbtn prtlrl th

xpnntl dtrbtn t b r pprprt An nrl l f dtrbtn h th xpnntl fl ld ld t nprtr d

hl pl l nrl dtrbtn th nn vrn nd xpnntl dtrbtn r th dtrbtn th th nn l prtr l prn

. Expnntl UMVU fr ES

Ettn f th ntt (Y n th xpnntl dtrbtn h bn vrd b

n rrhr Ettn f (Y hr bth nd Y hv dbl xpnntl dtrbtn vrd n l t l (5 In th prdn ppr dbl xpnntl dtrbtn th nn l prtr nd nnn ltn prtr h bn

ndrd h xpnntl dtrbtn vr ttrtv h b f th

20 2 rl prprt nd vrl thr ntrtn prprt h th hrtrztn bd n blt dffrn (r nd bn 197 Sth nd Shh (191 hv

xplrd th lr bnd f th vrn f th ttr f P (Y X ), hr Y nd X

r dtrbtd xpnntll th prtr λ nd μ h hv l xplrd th bnd fr th Mn Srd Errr f th Mx lhd Ettr hn n f th t prtr λ nd μ nnn

hr r vrl thr td n th bjt tht t vdnt tht

ttn P (Y X) n th xpnntl tp ndd pplr prbl Expl f th td r Ivhn (199 Crr nd Cp (1997 Al t l ( nd MCl

(1991 h flln rlt drvd n th xpnntl dtrbtn fr t rnd vrbl h thrtl vl f ES dntd b

nbd ttr f , ndtnd b th complete sufficient ttt ld b th 22 UMU estimator. We will show that the following unbiased estimator of (Y > X ) would serve the purpose: I (Y > X 1 ) where

Hence, this estimator would be given by the following expression

Note that Al and X 1 are conditionally independent of each other. In other words,

Al 1 s it is independent of X 1 s , which would be clear from the following derivation h t n l b vd th n f frtn nvlvn bnl rnd vrbl Note that both forms of the UMVU estimator are valid for m >_ 2. td th fnt pl prprt f th UMU ttr ln th th MME

ttr Int Crl ltn r prfrd th rn f vl f λ 1 nd λ

h z f th pl drn fr th t xpnntl ppltn r tn t b 3

nd v thnd Int Crl ltn r dn n h h tt r

vn ln th th n rd rrr (MMSE n bl 31 h MSE vl fr th 26 MAE tt r prbl t th ISE f th EUE Sn th IE r t

pt nd th UMU ttr d nt v n ddd dvnt vr th EE fr th ISE nrnd t prfrbl t th plr ttr CHAPTER 4

KERNEL DENSITY ESTIMATION

4.1 Approaches

Crnl dnt ttn n b rlzd th ltn pr f th aeage sie

isogam (AS pprh rtll ll nnprtń dnt ttn lrth n b hn t b pttll rnl thd (Stt 199 h Geea Kee

eoem d t rrll nd Stt (199 tblh th

Gvn dtrbtn fntn th dnt n b rttn

ndtr fntn n th tn bv n n rnl fntn K ( nd rrv

t th Crnl dnt ttr

h rnl tt f th dnt fntn n b rttn 7 h th b d f rnl dnt ttn

h kernel density estimator ntnd bv l lld th rznrr

nbltt ttr th hn kernel function K (.) dfnd (A) drbd

bv

r n th nbr f brvtn i thrh n Althh th r

ppd t b ndpndnt brvtn fr th dtrbtn th rnl thd

ftn d hn th ptn vltd r v lld th bandwidtv r th smootving operator. It ntll th hlf lnth f th nd n hh th

thn t pl

r dtld drptn f dnt ttn n n l t n f th flln rr Stt (199 ndl t l ( Slvrn (19 Azzln

(191 Shlt nd Qrbrr (1971 nd nn (19

h rnl dnt ttr bntn fr th rnl ppld t h

vltn pnt h th ttr nhrt th prprt f th rnl h phnnn rphll xprd n th dr (r 1 h dnt vn thr r ptd fr th dt n nthprtnv dr th xpl ntrdd n

Chptr h rnl fntn r nlrd b l f tn t nhn th vl

fft Τ • .. • • , • • , 0 th nbr f brvtn flln nt tht bn ntd Eh f th brvtn

vn l ht nd tht ld th rtnlr htr In rnl dnt

ttn lr pprh tn nd n ntrvl f th lnth t h th bnddth tn rnd tpl vltn pnt h brvtn flln nt tht

ntrvl r tlzd t ntrt th rnl tt nd ht nd t th pnt

n h tht th pnt lt t th ntr t th hht ht nd th pnt frtht fr th ntr t th lt ht h phnnn xplnd

rphll n th dr (r

S f th pplr h f rnl r vn n bl 1 Whl vltn th prfrn f th rnl dnt ttr t prtnt t h n pprprt l fntn tht ll b bl t pr th fttd dnt vr th hl pprt An

xptd l fntn nn th r n b lltd b vrn vr ll pbl l vl Mn Intrtd Sr Errr (MISS n h h nd th

prd t n rbtrr rnl fntn (Slvrn 19 h bl Keg rprnt th Epnhnv rnl It h bn ll tblhd tht ndr th ptn f

ndpndn th Epnhnv rnl tprfr t f th tr rnl fr

ffn ndrd S Slvrn (19 fr r nfrtn 31 bl 4. Ch f Crnl

Althh thr r rltvl f td n th ffn f rnl fr dpndnt dt th ndpndn ptn ftn vltd n rl lf prbl nd

t t f th prprt f th dnt ttr tll hld ll t l (1995 hv

hn tht vn n trnl dpndnt dt n pttll ptl bnddth fr ndpndnt dt d h ln rlrt ndtn

(h xtn f th xth drvtv f th tr dnt r tfd In th ppr th hv l hn tht th MISS xprn fr th dpndnt pl h

lr fr th MISS xprn fr th dnt tt fr n ndpndnt

pl A tpl hrt f th ffn f thr rnl prd t th Epnhnv

rnl vn n bl 2 bl 4.2 Effn f Crnl Cprd t Epnhnv Krnl (Sr Slvrn 19

r 4. UUnvrt rnl dnt tt f th fft f t bld prr lrn dr ln th th Epnhnv rnl t th vltn pnt n bnddth = nd 5

Gvn n r 3 nd 5 r th plt f UUnvrt dnt tt f

th bld prr vl n dffrnt bnddth nd th Epnhnv rnl h

bnddth th thn prtr h lrr th bnddth th thr th

rv If th hn bnddth t ll t ht nrt pr rhn nt th

dnt On th thr hnd f hn bnddth t lr t ld th t th

rv bnd n ptl nt hrb t ld ntrd b nt th dnt ttn prdr h thn rtrn n b lltrtd n lrr bnddth

th th t f dt pnt

r 4.4 Unvrt rnl dnt tt f th fft f bld prr lrn dr ln th th Epnhnv rnl t th vltn pnt n bnddth =9 nd 1

Cndr th xpl n Chptr h t f ll pbl dffrn fr th

dt n bldrprr dr 31 (hh rd Evn th th h vl

f dt t n b n tht th ll bnddth rh pt ld rf r th

xpl f dnt r ptd prtl th phnnn ll rf

h lltrtn f th vn n th r 3 nd 5 h hn bnddth n

th r ln th frt nd nd r r ( , (9 1 (15 rptvl

ht th frt r n th r 3 rrpnd t bnddth f nd th nd

r rrpnd t bnddth f . h nrl ntn lr fr th dr th

dnt tt b rh thd nd vrrthd th th f lrr nd

lrr bnddth 4

r 4.6 Unvrt rnl dnt tt f th fft f t bld prr lrn dr n vrl rnl nd th bnddth

In th r th dnt plt rrpndn t th rnl r lr-dd fr prn Whn dffrnt rnl r hn pn th bnddth fxd th

tt d nt vr t h h plt ld ht lltrt th r vn rnl r d fr th thn prtn nd th ttd dnt f th dffrn plttd n th fr

nvtt th dnt tt th vrn h f rnl n

xprnt ndtd th th dtt nl th vrbl dnt ttn rlt n dt nd dffrnt rnl r vn bl h frthr lltrt th ft tht h f n f th fntn rnl fntn lttl dffrn n th

vrll ttn thd

bl 4. Cprn f nt Ett fr ffrnt Crnl Un th S nddth f 15 6 h kernel fntn ll hn tf th flln prprt

h ptt dtrbtn f th rnl ttr rrdl f th hn rnl

vn b ( ( + βλ σ2 hr f (x) th tr dnt nd th thr ntnt

r vn b

t tht th bias factor fax dpnd n th hn kernel ll th bnddth

(v) nd th nd drvtv ( f ( f th tr dnt vltd t th pnt x

hrfr nztn f bias ld nvlv pprprt h f th kernel nd th bandwidtv.

t th h f th kernel nd th bandwidtv ld fft th vl f σ

n th l ld b t fnd ptl kernel nd bandwidtv t nz bth bias

acoβ nd vrn σ h nvntn t nz th Integrated Squared Error

('SE), mean integrated square error (MISS) r th pprxt frl fr th MISS

(AMISS).

hr r thr fr f l fntn tht ld ld t dffrnt tp f oima awi On h xpl th Kuack-eie iomaio vn b

hr K th rnl fntn nd μ th nd rdr nt th rpt t th rnl fntn nd th tr dnt ffrnt bntn f oss ucios kee ucios ld v dffrnt ptl h f awi nd hn dffrnt

esiy esimaes

lr (199 h xplrd th ptl h f smooig aamee

(awi n oosa Intd f ptn th ntrl fr th dd l fntn h d th oosa mea nd oosa aoimaios fr ntrl h

hn tht th ptl h f bnddth fr th thd nd th th ptl

h n kee esiy esimaio

h nd rz ( hv prd vrl bnddth ltn thd n kee smooig f OC cues hr prl td h tht th Ama smooig meo prfr bt nt th n prd 38 4.2 Estimation from Dependent

Krnl dnt ttn thd ppld n dt tht r d t b ndpndnt

pndnt dtt ppr ntrll nd thrfr r ftn d t tt th dnt

A rlt tt tht r nfrr n tr f lrr variance r btnd If th ntr f dpndn nn thn n prvnt n b xptd n tr f lr vrn r t lt bttr bnd f th pbl b nd vrn n b btnd th th xtr nld f th dpndnt trtr n thd fr rdn th b r th vrn n b dptd t frthr prv t h t l prtnt nd fl t n f th dtt dpndnt nd f t ht th ntr f h dpndn

Whn dnt tt r ptd fr ll pbl dffrn f th t

ff vrbl fr ndpndnt pl nl th vrn f th tt dtrrt nd th b rn nfftd h ptt prprt f th tt

h normality, rdtn f bias (slow) witv increased sample size, rn t b

ttrtv bfr If th xt xprn f th vrn btn th rnlr

hd vrbl r nn thn n n p th vn trnr rlt h

rzd nd prvd bl

New Result 4.2.1 t 2 m nd Al A2 An b ndpndnt pl fr t nnn dtrbtn E nd Y n ntn dnt fa nd

fl rptvl t Al A2 WM b th lt f ll pbl dffrn f X nd A 39

generalized Hoeffding's theorem, or the generalized Rurstatistics. For more detailed discussions on the generalized Rurstatistics see Lehman (1963).

Result 4.2.2 In the above set up, let f,,, be the true density of the

the bandwidth used and μ ιι 2 K(

The expectation is exactly equal to the expectation of the density estimate obtained using independent data. The reason of equality is the well known fact that even in the case of correlated random variables the sum of expectation is the expectation of the sum. (n th ft tht th M rnd vrbl lthh dpndnt r rtnl dntll dtrbtd h n b rttn th flln xprn

lt x v B = —t, hn B = x + vt nd dB = vdt. hn th bv

xprn b th flln ntt (t tht ( ntn dnt fa , hh bn ttd

ll tht th dnt tt ptd fr th dpndnt dt prfr

lt ll It h ll th n rtrn ptt prprt nd nrlt h b fntn l l t th n btnd n th f ndpndnt dt h nrl blf tht th bnddth ltn thd tht r fr ndpndnt dt r nt

t pplbl n th f dpndnt dt vr thr rlvnt r b ll

t l (1995 ddrn th thd f bnddth ltn n th ntxt f dnt 4 ttn fr dpndnt dt In th ppr rfrrd bv th hv hn tht vn

n trnl dpndnt dt n th pttll ptl bnddth ptd

th th ndpndn ptn d h A ttr f ft th ndr dpndn ndd b th rnl fntn ppld n th dpndnt dt trtr h

t trnr nfln thn th rnl dpndn rdn t th ppr

h trtr f dpndn n th nr drbd bv n b frltd

th th vrn trx vn n th flln dpl t th vrn trx f th m x n dt pnt btnd fr ll pbl pr dffrn b dntd b Σ

r j r 1 — Χ ; ( = nd j =1 n nd th th r

dntll dtrbtd lthh th r nt nrl ndpndnt rthr dntn

th trx Σ Χ n b rttn th flln xprn pl npltn th bv trx Σ n b rttn

r O dnt th KKrnr prdt f tr I dnt th dntt trx f rdr m x m J dnt th x trx th ll th ntr l t nt Ρ 1 nd 2 dnt th tr vn bl

If th tt f th ntt σα σα nd σ2 r vlbl thn n n

l tt Σ

Α ld fr xprn f th nvr f th vrn trx n b btnd flln th rlt f Mllr (191 h xprn n trn n b d t pt th th rt t dd nd b f th flln t rn Wtht

ptn bt lnr bntn f th tr dnt flln nt th fl f dnt th pprh nnt b d fftvl In ddtn n nnt xpt

nrrtd pl t b ndpndnt Onl xptn fr bth th rtrtn hn th dt r rnd pl fr th nrl dtrbtn

4. Sltn

An xprnt th nn dnt ndtd n th ntxt f dnt ttn fr

ndpndnt dt vn bl h l f th xprnt t h th dnt

tt ptd fr dpndnt nd ndpndnt dt pr th h thr

d n th thrtl rlt dd n th prdn tn n n xpt

prbl rlt fr th t nd f tt h tt fr pltl rnd pl pt bnhr t jd th prfrn f th tt fr dpndnt pl hr th dpndn rtfll ntrdd pn n nd th

td f t dr dd n hptr Whrvr vlbl th tr dnt d n th xprnt

h ndpndnt dt r pld fr Ν( 2 ppltn th dpndnt dt

r btnd fr t ndpndnt pl f N(0,1) nd N(1, 1) ppltn In th

f th dffrn f th t nrl ppltn N(0,1) nd N(1,1) l th 44 r pr th prfrn f th t dnt ttr th tr dnt l d

n th xprnt

bl 4.4 Cprn f Ettd Mn Intrtd Srd Errr f nt Cptd fr Indpndnt nd pndnt t

h MISS ln th th pl z d n th dnt ttn l

vn In th ttn th Epnhnv rnl d nd bd r vldtn

thd d fr th ltn f pttll ptl bnddth h MISS

lltd n th flln xprn

h thd f MISS drbd n Sn t l (199 r ](x) nd fax)

r th ttd dnt nd th tr ndrln dnt rptvl h nbr n th nbr f vltn pnt f th dnt hh hn t b thr 51 r 1

h rn f th x vl hn fr th dnt tt r btn - nd t nr th nln f ll th prbbl pl fr h f th tr ndrln dnt

h ndpndnt dnt tt r lltd n nbr f dt pnt

hr vr fr t 3 On th thr hnd th dpndnt dnt tt r 4 lltd n ll pbl dffrn f t rl pl h f z 1 t 15

h nbr r xtl hlf f th pl z tn fr th ndpndnt dnt

N tt h thr r nbr f dpndnt dt pnt nd jt l n th prv N vr fr t 3 Intrtnl t brvd tht th dnt

tt rrpndn t th dpndnt dt r b fr lt bttr thn thr

ndpndnt ntrprt h bl lltrt th fndn

MISS fr dp & End dt

r 4. Mn ntrtd rd rrr (MISS prn f th dnt tt ptd fr n ndpndnt pl nd dpndnt pl

h MISS vl ptd fr dnt tt bd n ndpndnt dt

ln th thr ntrprt (dnt ptd fr dpndnt dt r vn n r

7 p th n th l th MISS fr dpndnt dt ltpld b ftr f t th prr MISS vl fr pl z thrh 5 t b prbl 46 n f th t f pln ntnt thn th ltn lrl h tht th dnt ttn fr th dpndnt dtt prfr bttr thn th ndpndnt

N t b n bth th pl th nbr f vrbl nd x

In r nl ntn f th dnt tt fr N = 5 vn ln

th th tr dnt nd th dpndnt dnt ptd fr th pr f nrl pl

h f z 15

dnt tt prd th th rl dnt

Figure 4.8 nt tt prd th th tr dnt

vr n n rrtl pnt t tht th tt ptd n th f

N ndpndnt dtt r bd n Ν dt pnt hr thr r x = dt pnt ( fr lrr nbr d n th ttn fr th dpndnt t n

vrll prn n th dpndnt ht b lrtv bt th `pr nt prn nt b prbl Intrtnl vn th flln xprnt h t tftr rlt 4

th th tt btnd fr th ndpndnt pl nd th tl dnt N(1,2).

r 4. nt tt fr vr lr nbr ( f ndpndnt brvtn

In r 9 th rprtd dnt tt fr th dpndnt dt ptd fr pr f ndpndnt pl f z h th rtfll nrtd pl h dtpnt

z h xtl l t th z f th ndpndnt pl drn fr th

N(1,2) ppltn t tht bth th dnt tt ptd fr dpndnt nd

ndpndnt dt prfr vr d

ll tht th dnt f (dffrn btn t dr th rpt t th prr ff vrbl h bn ptd fr th dpndnt dt It h l bn

ntnd tht th dnt h th pnt- rtd ntn nd b tht 48 unaffected by the particular structure of this dependence. However, the ultimate goal is to

utilize this as an measure.

bl 4. Estimated Arobabilities Along with the Mean Squared Errors

Given in Table 4.5 are the different possible values of the difference ( and the estimated probabilities for the data set in Table 2.1 in Chapter 2. The mean squared errors based on betstrap are also given along with these values.

fix ideas, note that the estimated probability of the difference being larger than

0 is given by 0.56744 (5.931e-05), where the quantity given in parenthesis is the bootstrap based mean squared error of this probability. For a randomly chosen subject, the probability of observing a favorable response under the application of treatment relative to treatment A is 0.56744, where the similar quantity based on Mann-Whitney statistics is 0.57541 (Chen and Kianifard, 2000). 4 bl 4.6 Ettd Arbblt Gvn Aln th 95% ttrp Cnfdn Intrvl nd Eprl Arbblt

Slrl n n l t vrl pbl vl f th dffrn nd th

rrpndn prbblt ln th t n rd rrr hrfr th pprh

v r lbrt ndrtndn f th dffrn nd th rrpndn bttrp bd 95% nfdn ntrvl vn n bl 5

Cprd t Chn nd KKnfrd ( th pprh f fft z r h

fndntl dffrn In th ppr ntnd bv th bldrprr vrbl

d t b drt bt n th prnt td t d t b ntn

(thr th xtn f th dnt nnt b d lthh th brvtn r drt

h pnt- 95% bttrp nfdn ntrvl f th prbblt f th dffrn vl rtr thn zr hrpr thn th nfdn ntrvl vn n Chn

nd KKnfrd ( Al bd n th td th rrpndn nfdn ntrvl f 0 th nrntl prbblt f brvn r fvrbl rpn fr trtnt rltv t trtnt A tht P(Y — Ρ( Y (1519 1 hh d nt nld hrb t r tht th dffrn nfnt t th 5% lvl CHAPTER 5

RECEIVER OPERATING CHARACTERISTIC (ROC) CURVE

5.1 Using ROC

Receiver Operating Characteristic (ROC) curve is a plot of `sensitivity' (correct assertion of disease) versus 'A — specificity' (incorrect positive) of a test. In other words, the probability of a diseased subject being correctly identified is `sensitivity' and the probability of a subject without the disease being correctly identified as healthy is

`specificity'. This curve is plotted with respect to the thresholds of discrimination of the test under discussion, where `sensitivity' is represented along the vertical axis and `Aur specificity' is represented along the horizontal axis. The concept of ROC has originated in the signal detection theory but is rapidly gaining acceptance in medical applications, several branches of engineering and psychometric applications.

References to ROC can be found even in classical regression problem and discriminant analysis, and data mining. The following section discusses some estimation problems in this area.

5.2 ROC from Density

Recall that the ROC curve is the plot of `sensitivity' versus `A — specificity' with respect to several thresholds of discrimination. If the observations from the diseased group is denoted as Y and the observations from the healthy group denoted by then the standard

way of interpreting the ROC curve is a = Y ( (A — where the distribution of A and are FY and respectively. The point is the survival probability of at a specified point. Also the of Y, i.e. (A— F) is denoted by i and the

51 2

nvr f th dtrbtn fntn f X dntd An tht th ltv dtrbtn fntn trtl ntn th vl f n Othr f th

trt ntn prprt rlxd thn rprnt th nrlzd nvr f th

ltv dtrbtn fntn h fntnl fr f th nrlzd nvr vn b th flln xprn

Obtnn th nvr f dtrbtn f fntn ftn t pltd fr thrtl pnt f v nd xpnv fr pttnl pnt f v

Anthr f rprntn th OC rv b n th flln nttn

E 1 (A = c n A— E (c) = VE (c) = h th OC rv plttd

( nt n b n ( = E (A (A — = Y (c vr F (c) In thr

rd th bv rprtrztn hlp dntf th OC rv th plt f th

rvvl fntn f th vrbl nd A hr th frr rprnt th hlth rp

f bjt nd th lttr rprnt th dd rp f bjt

An prtnt f OC rv t vlt prfrn f tt tht hv bnr dn p nd r bd n ntn tpt If th OC rv bd n

`tt A nrr t th ( A pnt prd t OC curve bd n nthr tt

`tt thn `tt A ld b bttr tt prd t `tt Aln th ln

ld tndrd tt ld hv OC rv n thrh pnt tht vr nr t th

( A pnt hh ld b dntd th iea oi fr n n h OC rv dpl th pbl trd-ff btn th t nd f rrr (p A997 S nthr

prtnt f th OC rv t dtrn th ptl thrhld pnt n rdr t

xz bth `ntvt nd `pft h xzn `ntvt 53 nd nzn A — pft

t tht th ( A pnt rrpnd t A% ntvt nd A% pft

p (3 h dtld dn n th tttl prprt f OC rv vr

f thr tt tht ld rndl lf th bjt nt dd nd hlth

rp thn th OC rv bd n tht tt ld b th ln f lt rprntd

h h f th ptl thrhld vl tht hld b d ld dpnd n

n ftr h th td t prvln f th d nd n

(p A997 In th bn f th t nfrtn n t h th ptl pnt

t t lt t th iea oi (vn ll

An ltrnt n ptl thrhld vl n b hn b hn th pnt fr pbl fr th ln f lt hh th OC f th d-h tt th tt tht rndl lf dd bjt fr th hlth n In th flln

tn n ttn thd f th ptl thrhld pnt ld b dvlpd n th dnt ttn pprh h rlt 5A nd 5 ld b d fr th

ttn lrth h bv rlt ttd tht prf n ld (

h pl bt fl rlt n b tlzd t btn th drvtv f th OC

rv t dffrnt thrhld pnt A drt f th bv rlt t fnd th ptl thrhld pnt bd n th xl vrtl dtn fr th d-h tt r 5A

n vrplfd ptr f OC rv nd th pnt n th OC rv th pnt frtht fr th ln jnn ( nd (A A

rf: A nrl dr f r prbl vn n r 5A An pnt n th OC rv vn b R (p). t th prpndlr dtn f n rbtrr pnt n th OC rv fr th ln f lt b Hap).

r . ndn th ptl pnt f drntn n th OC rv

ndn th ptl pnt fr drntn th rpt t th t nd f pbl rrr n prbl Ιι lt rrn t n t r

lr prbl r xpl lt lt rrn tn b vn th flln 6

Althh th π vl n b ttd b fttn th lt rrn rv th r ntll th n f th rnl , . S t rn t prdt r tt th pbl , vl fr th btnd tt f th π ; vl h v r t drntn prbl nd lthh hn n th flln th nvntn th nt nrl th bt h f π ο

h fntnl vl f th ntt p Ramp) — p • hrfr th r f th

triangle drawn by the points (0,0), R and (A,A) is given by p ρ n th ttl

r f th trnl nd th trnl frd b ( (A A nd (A ld b

Ρ +A ] , [ίρ — hh trvll lr bnd fr th r ndr th OC rv

t tht th OC rv d t b nv nd n prtl ttn th

nt b th In OC th thtll lrr vrbl ( (Y c _ A d

ll rprntd ln th vrtl x vr nv OC n b flppd f

th thtll lrr vrbl rprntd ln th hrzntl x In th rnl

fr f th OC rv th rprntd tt h t b t lt d th d-h tt

thrfr th rv t bv th ln f lt

. Ettn th rvtv f OC nd th AC Un th nt

h flln lrth ld b fl t tt th vl f c th ptl

thrhld vl n f thr pl f xd brvtn fr nd g thn thr

lftn nt n rp r th thr n b dn f n ndvdl brvtn fll n

th rht d r th lft d f c

Stp Ch n ntrvl f thrhld pnt C h tht th t xld th pnt

hr thr f th dnt vl b zr Clrl th ptl thrhld pnt f

xt ld bln t th t C Step 5 nd th ptl vl c, hh rrpnd tr =A

Step 6 Sn th rrpndn p r lrd nn t ld b t t b t th rnl ( Y vl

fnd rnbl rrr bnd fr th ptl c *, n n ε ε A h tht C th t ntnn fr hh th r vl btn [A— εA + ε] r 53

ld r lrl lltrt th ptl prprt f th thrhld vl nd l th ft tht th rt f th dnt l t n t th thrhld pnt

r . h ptl thrhld vl

vr th lrth drbd n th tn rnt th xtn f th

ptl pnt th n xptn f th trvl f pltl prtd dnt r lt pltl dntl dnt h nn n b hn fr bdl dtrbtn th nv OC rv If th OC rv h v thn th ptl pnt n b hn fr vrl nddt pnt n hh nl t hn

lbl xtr fr th nddt ll xtr

.4 OC Mr f Eff

A rprtrzd vrn f th OC rv th plt f th t rvvl fntn f th

drn thrhld vl h vrn f th rv n b d n th td f fft

z lln rb t l ( n n rpl th ntn t f th dd ppltn (Y I ° nd th hlth ppltn (Y I ° b A nd X rptvl

hr A nd X dnt vl f th prr ff vrbl fr th dr ndr td

h OC rv n th ntxt ld ppr t b lr t th ideal point f th t

f th r ff dr rprntd ln th vrtl x n tht hhr vl f th t ld rrpnd t bttr ff

Sn th rvvl fntn f th t ndrln vrbl r ptd t

vrl pbl thrhld n n pr th rrpndn prbblt t th thrhld vl On th thr hnd n n rz th hl OC fntn nt

nl vl nl th r ndr th rv (AUC hh n b hn t b l t

P(Y X) . S th OC rv v th prn f th vl P( A c)

nd Ρ (X > c) fr dffrnt vl f nd th r ndr t n tt f th

ntt PAY X) .

A fntn ll rltd t th rprtrzd vrn f th OC rv th

vrtl hft fntn (A vn b hr (A Ι ° h th dtrbtn E nd (Y Ι ° h th dtrbtn r nd

dnt th t ndrln prprt f th ppltn bn ndrd r

xpl ld b th plb rp nd th rp hr th dr ndr td h bn dntrd h rltn btn th OC rv nd th vrtl hft fntn dfnd bv vn n Ght nd rd (7

r R(p) th OC rv nd th fntn A( dnt th vrtl hft fntn

r rl dvlpnt f th hft fntn n th ntxt f t pl prbl

(A97

n th hft fntn n l b tlzd n th fft z ttn r

xpl th n hlp n th ttn f th r ndr th OC rv ndr dffrnt thrhld vl h n trn ld b fl t dntf th prr dr hn thr r t dr ndr td

h flln t rlt 5A nd 5 r pl f th rlt b Ghh

nd ń (7 hr rlt bd n Generalized Rank Set Samples aGRSS) nd n th prnt ntxt plfd fr th f Simple Random Sample aSRS). h t rlt vn bl n b fftvl d fr th ttn f th pnt- vrn

f th OC rv nd thn tlzd t rt nfdn bnd fr th OC rv h

n l b xtndd n fndn nfdn ntrvl fr th ES btnd th r

ndr th OC rv

lt .4. If t Simple Random Samples (SS f z m nd n r lltd fr t ppltn hr th ppltn OC rv dntd b thn th

prl OC rv vn by h th flln ptt prprt Here q lies in the open interval (0,A) , q denotes the minimum of p and q f and f are the densities corresponding to the distributions E and F .

Therefore if we call the expression in (5.A) as K( then a point-wise confidence band of the ROC curve can be constructed inverting the above relations. This is given in the following equation

tndrd nrl prntl th r t th rht l t α 2.

Note that the empirical ROC curve ( R ) mentioned above is computed from the raw data just like the empirical distribution is computed. The empirical ROC of the example of the double-blind drugs introduced in chapter 2 is given in the following 62 r 5 h hrzntl x rprnt th dr A nd th vrtl x rprnt th dr

EprEl OC rv nd Cnfdn nd

r .4 Eprl OC rv nd 95% nfdn bnd

d n th thd drbd n th bnnn f th hptr ( r 5

n tt f th r ndr th prl OC rv ptd h vl f th prbblt rrpndn t th ptl pnt f prtn vn b 779A th nttn fr th pnt p *. h rrpndn OC rv vl Rap *) vn b

99A55 hrfr th ttd r ndr th OC rv vn b

prn f th tt fr dffrnt thd h xpl f th dbl- blnd dr d n th fft z rnt d n th thd dnt tt (S Chptr d n ptl pnt f prtn (S rlr th hptr t d n nrl nn-Stltj ntrtn ° d n Eprl dtrbtn fntn

iema iegaio dl th fndn th r ndr rv ( n bndd

ntrvl [a ] hr th ntrvl dvdd nt fnt nbr f bntrvl e

h th r ptd b th n f rtnl

A r nrl f th nn ntrtn th iema-Siees iegaio ( Aptl A99 h nvlv t fntn In th prnt dn th t fntn r (c nd ( (c rptvl h ld dl th th

f th fr Σ (t Δp (ll tht th rnl vrbl c th thrhld vl nt k= rprntd n th OC rv t n tt f th ES th n f th ppr

nd th lr f th ntrl ptd n nrl nn-Stltj

ntrl

5.5 Numerical Results

h nfdn ntrvl f th OC rv bd n th xprn vn n th tn

(5 vn bl (bl 5 h rprtd vl f nd ( r th prl vl ptd fr th dt t vn n tbl A h nfdn ntrvl th SS bd rlt plfd fr th nrl rlt fr GSS Ght nd r (7 64 h Cnfdn ntrvl f th prl OC rv rnbl hrp t tht t tll pnt nfdn bnd bd n th tndrd dvtn f th

OC rv vltd t rd f pnt n th lt 5

bl .2 Cnfdn Intrvl f OC Crv

h ttn lrth fr th ptl thrhld ppld t th bntn f nrl vrbl ld th flln rlt Spl f z hr dnt r

r drn fr th Y nd dnt nd C pnt r ttd fr th fttd dnt ( tn 53 n th rrnt hptr prtd vl r th dn

tt btnd fr rpltn f th pr Gvn n prnth r th 6 dn blt dvtn f th tt

bl . Ettd Optl hrhld l

h ntrth brvtn hr tht th tt r rnbl tbl vn

hn dnt r ttd n fr nbr f dt pnt lthh th n

rd rrr r rltvl hhr fr th ll pl z CHAPTER 6

CONCLUSIONS AND FUTURE STUDIES

h jr fndn f th td th ft tht nfrtn fr dtt th hv dpndn n b xtrtd th th f tl prvdd Al dnt ttn

thd nd prtlrl rnl thn n b d n ff rnt h

ttd dnt h th n rtd ntn nd ld llr MISS prd t th dnt tt ptd fr ndpndnt dt th hv th fr f th b fntn

Cnfdn ntrvl bd n bttrp nd dbl bttrp thd r t

fftv n th ntxt f fnt r nfnt dnnl prbl l dnt ttn

Gvn tht n th rl rld n h t r th llr dtt hh r ftn

prft nd dpndnt th td n xpl hr hv ptn n rtnl

vr f th hrtn n n fftv Eff rnt prbl tht ntntl ndr f n lnl td In th rrnt f dvnd

ptn bth th prbl nd th pprh trd t ltn n b ddrd thrh dvlpn ffnt lrth nd prr

hr r n pbl th rrnt td n b xtndd n dffrnt drtn

(1 hrtl nd nr plnttn nd dvlpnt f dbl bttrp n dpndnt dt

( t fnd thrtl tt f th dnt hn th dt th th

vrn vrn trx = I O P + (J — I O Ρ thr nn r tbl

(3 dpndnt dnt ttn n b tlzd n nn-prtń rrn (thn thd n dpndnt t p

66 67

( Gnrlz ltn td t nld nrl xtr dnt

(5 Appl th nnprtr n thd t tt th OC rv n Ixtr f rht Ar (MM prr h n b dn b prdn n Ernl t l (

( S ptt rlt n th nrl fr f th rnl vrnt r xpl f th ndrln dtrbtn nrl ld fr xprn n b btnd fr th vrn ftr th ppltn f th rnl fntn Slrl n nn ntn dtrbtn f th ndrln dnt ld v prn f th rlt APPENDIX

SOURCE CODES

Some selected source codes written in R are included in this section. R is the free version of the S/Splus software (Ihaka and Gentleman, A996 ). The R packages along with relevant packages are available for download for free from the comprehensive R network, http://cran.r-project.org/.

The R version 2.3.A is used for the present study along with the editor Tinn-R version

A.A7.2.4, available for download from the following website http://www.sciviews.org/Tinn-Ri.

Each of these codes is linked with one or more chapters. There are several lines of comments included in each code to clearly explain the objective.

The following program is used to compute the UMVU estimator in the exponential case. See Chapter 3 for the related derivations. 69

} rtrn (b

} END OF PROGRAM 1

h flln d d t d th Mnt Crl ltn f th ttr b rptdl lln th bv rtn h tpt r rrdd n fl nd vd fr pt prn h flln prr llt th bttrp dnt ttr fr th dtt

ntrdd n Chptr nd d rptdl t lltrt n f th thd tht dvlpd n th rrnt td 71 = esiy( w="c" kee="eaeciko" om=-o = =1; = om(y$ mea=1 s=sg( og = ASE

a=seg(11y=; o([a]ce=751y=ye=""a=""ya="esiy" a=" aues"maiaesiy esimaes comae wi e ea esiy" yim=c( co="ue" c=w=

ci(ay$[a] ais (1 a=c (1 1 3 39 9 aes=c (- -5 - 1 7 as= ois($y[a] coae" c=15 ce=751y= yea"w= ois(y$y[a] caae" c= ce=751y=3 ye""w= eg=c("ea esiy" "es-es ie" "es-es ee"; ege(3 eg co = c("ack" "e" "ue" c=c(15y=c(13 w=c(

ea e oigia aa =eacs("/couses/eseac/ciica/aa_ρ_a_cs " eae=UE Cacuae e ieece = i([1]ρ[] Β = 5 ss=;

= maoec(51(Β+1 ecae e ace oig aiae i e as coum wi e aues [(+1]=esiy( w=""kee="eaeciko" =51om=- o =$χ

ow sa e oosa esemig

o (i i 1

{ = same eace= = esiy wa"kee="eaeciko" =51om=-o = esiy as ee eauae a e ie aues [i]=ss$y Sae us e y }

= seg(-y=5 = a o ec (17 o(i i 1 { [i]=ay(asaay(1yC[+][i]} I = ay(asaay(mea SS = ay(asaay(1a ISE = ay ((-I 1 mea e oaiiies o e aues gie wi e MMSEs ci( ou(1-Iigis=5 ou(MSEigis=

oosa 95 CI o e esimae oaiiies ay(asaay(quaie ρo=c(5975

E O OGAM 72 The following program is self explanatory. The ultimate goal of this program is to utilize the density estimate and find the efficacy measure following the methods described in Chapter 4. ie = ase("/AA/yC/OOesiy_ "1"" see=" ome ie = ase{"C/AA/ΒΟΟΤesiy_ "Β"" see=" I

o (i i 1

= same(y eace= Y = esiy( wac" keeaeaeciko"om=owy o=iy= Y=ci($$y Sae us e a yes wieae(Y ie=ie[i] Use wie ae o wie i e ies }

EA I OW a= maοec(51 ecae e ace oig aiae

o (i i 1

{ = eaae(ie[i] ea e aes i is em a [i]=$ Sae oy e eauae esiy }

m( ow us eee a eai a

is is ou esiy i wou ae e aues meia aues/ 5 a 975 aues &a; 5 coums

ou_e = maoec(515 ou_e [ 1 ] = Y [ 1 ] ou_e] = ay(a meia; ou_e] = ay(a; ou_e[c(5] = ci(ay(a meia ay a o (i i 151

{ ou_e[i3] = guaie(a[i ] oe= 5; ou_e[i] = guaie([i]o=975;

}

a(ce=7 ceais=1 cea=1 cemai= o(ou_e{] c=e+e yim=c(35 ois (ou_e [ 3] coae" ca" ois(ou_e[] co=ue" ca"

ois(ou_e[]+ou_e[5] co=gey" c="" yea" ρois(ou_e[]-ou_e[5] coakaki" ca" yea" CC = seq(- y=5 yC (CC [ 1 3 ] ou_e [ 1] a[ 1 ] say((CCyC = ou_e[1]=a[1] myu - ucio(y {y[wicmi(as( -y]} ay(asaay( myu y = ou_e [ I] m(Yieaou_e

E O OGAM 4 74 h flln prr ll b d t pt th vrn rnl f th

Gn pr ndr pf pnt h rlvnt thr n b fnd n Chptr 5

t tht th thr tp trntn n fr GRASSERS to SRS, thn fr th

hft fntn t th OC thn bth th vltn pnt fr th rnl tn t b th

In thr rd KRSRS(p, q) tn t b KR,sRS (P, p). S tn 5 n

Chptr 5 fr r nfrtn # END OF PROGRAM 5 #

h flln fntn ll pt th pnt nfdn ntrvl fr th

prl OC rv bd n th vrn rnl xplnd bv hn th

vr prbblt nl th vl f th ntz fntn fr th tndrd nrl dtrbtn nd t b hnd h rlt jt l th rlt d n th bv prr r vn n tn 5 f Chptr 5 6 REFERENCES

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