e xpe rime nts de sig n a nd ana lysis
play

E xpe rime nts De sig n a nd Ana lysis F o tis E . Pso mo po ulo - PowerPoint PPT Presentation

E xpe rime nts De sig n a nd Ana lysis F o tis E . Pso mo po ulo s CODAT A-RDA Advanc e d Bio info rmatic s Wo rksho p, 20-24 Aug ust 2018, T rie ste , I taly A sho rt intro to me 2 Bio info rma tic s a nd Da ta Mining


  1. E xpe rime nts De sig n a nd Ana lysis F o tis E . Pso mo po ulo s CODAT A-RDA Advanc e d Bio info rmatic s Wo rksho p, 20-24 Aug ust 2018, T rie ste , I taly

  2. A sho rt intro … to me  2  Bio info rma tic s a nd Da ta Mining  to o ls a nd pipe line s to a ddre ss do ma in-spe c ific q ue stio ns  g e no me -a wa re me tho ds Bio info rma tic s  Bio info rma tic s a nd Clo ud Co mputing  wo rkflo ws a nd pipe line s o n c lo ud infra struc ture s Clo ud Da ta  sta nda rdiza tio n a nd re usa b ility Co mputing Mining E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  3. Bio a na lytic s Gro up @ I NAB|CE RT H 3 Re se a rc h  NGS Wo rkflo ws  Omic s Da ta I nte g ra tio n  Da ta Mining T ra ining Pe o ple NGS Da ta Ana lysis using 1 st So ftwa re Ca rpe ntry  Ma ria K o to uza , PhD Stud e nt Clo ud Co mputing (Oc t 2015) Wo rksho p (Oc t 2016)  Ma ria T sa yo po ulo u, PhD Stud e nt  Atha na ssio s K intsa kis, PhD Stud e nt E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018 CE RT H Main Building

  4. Why do we pe rfo rm e xpe rime nts? 4 Go to www.me nti.c om and use the c ode 45 89 48 E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  5. Wha t is a n e xpe rime nt? 5 An e xpe rime nt is c ha ra c te rize d b y the tr e atme nts a nd ime ntal units to b e use d, the wa y tre a tme nts a re e xpe r assigne d to units, a nd the r e sponse s tha t a re me a sure d. 1. E xpe rime nts a llo w us to se t up a dire c t c o mpa riso n b e twe e n the tre a tme nts o f inte re st. 2. We c a n de sig n e xpe rime nts to minimize a ny b ia s in the c o mpa riso n. 3. We c a n de sig n e xpe rime nts so tha t the e rro r in the c o mpa riso n is sma ll. 4. Mo st impo rta nt, we a re in c o ntro l o f e xpe rime nts, a nd ha ving tha t c o ntro l a llo ws us to ma ke stro ng e r infe re nc e s a b o ut the na ture o f diffe re nc e s tha t we se e in the e xpe rime nt. Spe c ific a lly, we ma y ma ke infe re nc e s a b o ut c a usa tio n. E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  6. Co mpo ne nts o f a n E xpe rime nt 6 T re a tme nts, units, a nd a ssig nme nt me tho d spe c ify the e xpe rime nta l de sig n  An a lte rna tive de finitio n is:  “tre a tme nt de sig n” is the se le c tio n o f tre a tme nts to b e use d  “e xpe rime nt de sig n” is the se le c tio n o f units a nd a ssig nme nt o f tre a tme nts  No te tha t the re is no me ntio n o f a me tho d fo r a na lyzing the re sults.  a na lysis is not pa rt o f the de sig n  Ho we ve r: it is o fte n use ful to c o nside r the a na lysis whe n pla nning a n e xpe rime nt. E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  7. Why T hink Ab o ut E xpe rime nta l De sig n? 7 E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  8. Crisis in Re pro duc ib le Re se a rc h 8 E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018 http://ne ilfws.g ithub .io /Pub Me d/pmre trac t/pmre trac t.html

  9. Co nse q ue nc e s o f Po o r E xpe rime nta l 9 De sig n…  Cost o f e xpe rime nta tio n. We ha ve a re spo nsib ility to do no rs!  L e c ious ma te ria l imite d & Pr e sp. c linic a l sa mple s.  Immor talization o f da ta se ts in pub lic da ta b a se s a nd me tho ds in the lite ra ture . Our b a d sc ie nc e b e g e ts mo re b a d sc ie nc e .  E ns o f e xpe rime nta tio n: a nima ls a nd c linic a l sa mple s. thic al c onc e r Slide s adapte d fro m “De sig ning F unc tio nal Ge no mic s E xpe rime nts fo r Suc c e ssful Analysis”, b y Ro ry Stark, 18/09/2017, CRUK-CI E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  10. So , wha t is a g o o d e xpe rime nta l de sig n? 10 Go to www.me nti.c om and use the c ode 45 89 48 E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  11. A g o o d e xpe rime nt de sig n 11  No t a ll e xpe rime nta l de sig ns a re c re a te d e q ua l!  A g o o d e xpe rime nta l de sig n must 1. Avo id syste ma tic e rro r 2. Be pre c ise 3. Allo w e stima tio n o f e rro r 4. Ha ve b ro a d va lidity  L e t’ s se e the se a spe c ts o ne a t a time ! Slide s adapte d fro m Gary W. Oe hle rt, “A F irst Co urse in De sig n and Analysis o f E xpe rime nts”, 2010 - I SBN 0-7167-3510-5 E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  12. 1. De sig n to a vo id syste ma tic e rro r 12  Co mpa ra tive e xpe rime nts e stima te diffe re nc e s in re spo nse b e twe e n tre a tme nts.  I f a n e xpe rime nt ha s syste ma tic e rro r, the n the c o mpa riso ns will b e b ia se d, no ma tte r ho w pre c ise o ur me a sure me nts a re o r ho w ma ny e xpe rime nta l units we use . I f re spo nse s fo r units re c e iving tr e atme nt one a re me a sure d with instr ume nt A a nd re spo nse s fo r tr e atme nt two a re me a sure d with instr ume nt B , the n we do n’ t kno w if a ny o b se rve d diffe re nc e s a re due to tre a tme nt e ffe c ts o r instrume nt misc a lib ra tio ns. E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  13. 2. De sig n to inc re a se pre c isio n 13  E ve n witho ut syste ma tic e rro r, the re will b e ra ndo m e rro r in the re spo nse s, a nd this will le a d to ra ndo m e rro r in the tre a tme nt c o mpa riso ns.  E xpe rime nts a re pre c ise whe n this ra ndo m e rro r in tre a tme nt c o mpa riso ns is sma ll.  Pre c isio n de pe nds o n the size o f the ra ndo m e rro rs in the re spo nse s, the numb e r o f units use d, a nd the e xpe rime nta l de sig n use d. E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  14. 3. De sig n to e stima te e rro r 14  E xpe rime nts must b e de sig ne d so tha t we ha ve a n e stima te o f the size o f ra ndo m e rro r. We will se e those in pra c tic e la te r.  T his pe rmits sta tistic a l infe re nc e :  fo r e xa mple , c o nfide nc e inte rva ls o r te sts o f sig nific a nc e .  We c annot do infe r ! Sa dly, e xpe rime nts e nc e without an e stimate of e r r or tha t c a nno t e stima te e rro r c o ntinue to b e run. E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  15. 4. De sig n to wide n va lidity 15  T he c o nc lusio ns we dra w fro m a n e xpe rime nt a re a pplic a b le to the e xpe rime nta l units we use d in the e xpe rime nt.  I f the units a re a c tua lly a sta tistic a l sa mple fro m so me po pula tio n o f units, the n the c o nc lusio ns a re a lso va lid fo r the po pula tio n.  Be yo nd this, we a re e xtra po la ting , a nd the e xtra po la tio n mig ht o r mig ht no t b e suc c e ssful. We c o mpa re two diffe re nt drug s fo r tre a ting a tte ntio n de fic it diso rde r a nd o ur sub je c ts a re pr e - adole sc e nt boys fro m our c linic . We mig ht ha ve a fa ir c a se tha t o ur re sults wo uld ho ld fo r pre -a do le sc e nt b o ys e lse whe re , • b ut e ve n tha t mig ht no t b e true if o ur c linic ’ s po pula tio n o f sub je c ts is unusua l in so me wa y. T he re sults a re e ve n le ss c o mpe lling fo r o lde r b o ys o r fo r g irls. • E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  16. K e e ping a c o mmo n vo c a b ula ry 16 1. T re a tme nts 2. E xpe rime nta l units 3. Re spo nse s 4. Me a sure me nt units 5. Ra ndo miza tio n 6. Co ntro l 7. F a c to rs 8. Co nfo unding 9. E xpe rime nta l E rro r 10.Blinding E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  17. T e rms a nd c o nc e pts (1/ 5) 17 e atme nts a re the diffe re nt pro c e dure s we wa nt to c o mpa re . 1. T r  diffe re nt kinds o r a mo unts o f fe rtilize r in a g ro no my  diffe re nt lo ng dista nc e ra te struc ture s in ma rke ting  diffe re nt te mpe ra ture s in a re a c to r ve sse l in c he mic a l e ng ine e ring ime ntal units a re the thing s to whic h we a pply the tre a tme nts. 2. E xpe r  plo ts o f la nd re c e iving fe rtilize r  g ro ups o f c usto me rs re c e iving diffe re nt ra te struc ture s  b a tc he s o f fe e dsto c k pro c e ssing a t diffe re nt te mpe ra ture s E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

  18. T e rms a nd c o nc e pts (2/ 5) 18 Re sponse s a re o utc o me s tha t we o b se rve a fte r a pplying a tre a tme nt to a n 3. e xpe rime nta l unit (a me a sure o f wha t ha ppe ne d in the e xpe rime nt; we o fte n ha ve mo re tha n o ne re spo nse )  nitro g e n c o nte nt o r b io ma ss o f c o rn pla nts  pro fit b y c usto me r g ro up  yie ld a nd q ua lity o f the pro d uc t pe r to n o f ra w ma te ria l e me nt units (o r re spo nse units) a re the a c tua l o b je c ts o n whic h the 4. Me a sur re spo nse is me a sure d. T he se ma y diffe r fro m the e xpe rime nta l units.  (e .g . in d iffe re nt fe rtilize rs o n the nitro g e n c o nte nt o f c o rn pla nts) Diffe re nt fie ld plo ts a re the e xpe rime nta l units, b ut the me a sure me nt units mig ht b e a sub se t o f the c o rn pla nts o n the fie ld plo t, o r a sa mple o f le a ve s, sta lks, a nd ro o ts fro m the fie ld plo t. E xpe rime nt De sig n a nd Ana lysis Mo nda y, Aug ust 20th 2018

Download Presentation
Download Policy: The content available on the website is offered to you 'AS IS' for your personal information and use only. It cannot be commercialized, licensed, or distributed on other websites without prior consent from the author. To download a presentation, simply click this link. If you encounter any difficulties during the download process, it's possible that the publisher has removed the file from their server.

Recommend


More recommend