;[6{  [48{ [6{  A Computer Tool for Use by Children with [48{ [6{ Learning Difficulties in Spelling [48{ [6{ [48{ [6{ [48{ [6{  Helen Pain [48{ [6{ [48{ [6{ [48{ [6{  PH.D. UNIVERSITY OF EDINBURGH 1985 [6{  [48{ [6{  If you want to look up the meaning of one of these words then type "lookup" after the w: w:lookup {lookup used by investigator to check if word in dictionary} Which word do you want to look up in the dictionary? w:fingers fingers = is not in the dictionary w:check What word do you want to check? w:eys Wait a minute while I check it It could be eyes yes easy eye If you want to look up the meaning of one of these words then type "lookup" after the w: w:check What word do you want to check? w:scelletn Wait a minute while I check it It could be skeleton called cellar collect If you want to look up the meaning of one of these words then type "lookup" after the w: w:check What word do you want to check? w:gostst Wait a minute while I check it It could be ghosts ghost gets guts If you want to look up the meaning of one of these words then type "lookup" after the w: w:check What word do you want to check? w:bodys Wait a minute while I check it It could be body bodies [6{  [48{ [6{  bodyless boy If you want to look up the meaning of one of these words then type "lookup" after the w: w:check What word do you want to check? w:tery Wait a minute while I check it It could be terry try they there If you want to look up the meaning of one of these words then type "lookup" after the w: w:check What word do you want to check? w:bloud Wait a minute while I check it It could be blood bloody blue bolted If you want to look up the meaning of one of these words then type "lookup" after the w: w:check What word do you want to check? w:francis Wait a minute while I check it It could be francis friends front finish If you want to look up the meaning of one of these words then type "lookup" after the w: w:check What word do you want to check? w:murderd Wait a minute while I check it It could be murder murderer murderous more If you want to look up the meaning of one of these words [6{  [48{ [6{  then type "lookup" after the w: w:rd:check Sorry, I cannot do that command I can check or look up a word w:check What word do you want to check? w:througt Wait a minute while I check it It could be through thought though that If you want to look up the meaning of one of these words then type "lookup" after the w: w:check What word do you want to check? w:throgt Wait a minute while I check it It could be through thought though that If you want to look up the meaning of one of these words then type "lookup" after the w: w:check What word do you want to check? w:throght Wait a minute while I check it It could be thought through though fright If you want to look up the meaning of one of these words then type "lookup" after the w: w:check What word do you want to check? w:sore Wait a minute while I check it It could be sure some so corner If you want to look up the meaning of one of these words [6{  [48{ [6{  then type "lookup" after the w: w:checkcheck Sorry, I cannot do that command I can check or look up a word w:check What word do you want to check? w:sour Wait a minute while I check it It could be sure so shout sound If you want to look up the meaning of one of these words then type "lookup" after the w: w:check What word do you want to check? w:souw Wait a minute while I check it It could be slow cow saw shout If you want to look up the meaning of one of these words then type "lookup" after the w: w:check, Sorry, I cannot do that command I can check or look up a word w:check What word do you want to check? w:opend Wait a minute while I check it It could be opened open opens opening If you want to look up the meaning of one of these words then type "lookup" after the w: w:goodbay Sorry, I cannot do that command I can check or look up a word w:goodbye Goodbye,francis % % [6{  [48{ [6{  Original [6{  [48{ [6{  Final Version [48{ [6{I  was  walking  along  the  road  looking  for  a  house  when  I  saw  lots  of [48{ [6{  fingers  and  eyes  looking  at  me.  I  began  to  run  but  then  I  saw  a [48{ [6{  skeleton  in  front  of  me.  I  screamed  and  then  I  fell.  Then  I  saw  lots  of [48{ [6{  ghosts around  me.  Then I  saw  a house  and  I rung  the  bell. Then  the  door [48{ [6{  opened. Then I  saw guts,  it was  very smelly.  I saw dead  bodies so I  called [48{ [6{  Terry . Terry came. He said he had found blood we went up to the room [48{ [6{  where  it  was  found.  I  touched  the  wall.  Suddenly  my  hand  went  through, [48{ [6{  then  we  heard  foot  steps.  Then  terry  fell.  He  was  murdered.  There  was [48{ [6{  blood  running  from  his  face.  So  I  ran  out  of  the  house,  up  the  street [48{ [6{  and called the police. [6{   APPENDIX B PHONCODE GRAMMAR AND EXAMPLES  In this appendix the following are presented:  (a) the grapheme-phoneme grammar used by the phoncode program;  (b) a sample of dictionary words, phonetically coded;  (c) example parses  of  words from  the  dictionary, according  to  the  grammar. [48{ [6{In  the  actual  program  the  phonemes  are  coded  as  integers.  In  this [48{ [6{  appendix  they  are  represented  with  their  character  codes  for  ease  of [48{ [6{  reading. [48{ [6{The  full  grapheme-phoneme  grammar  used  by  the  phoncode  program  is [48{ [6{  given  in  figure  B-1.  Tied  graphemes  are  indicated  by  a  "1"  preceding [48{ [6{  them  and  segmentable  graphemes  by  a  "0". All  'vc+e'  graphemes  are [48{ [6{  segmentable,  and  are  indicated  by  "*"  (for  a  further  explanation  see [48{ [6{  section 7.3.5). [48{ [6{A  sample  of  words  from  the  phonetically  coded  dictionary  is  given  in [48{ [6{  figure B-2. [48{ [6{Parses  of  four  words  from  the  sample  dictionary  are  illustrated  in [48{ [6{  figure  B-3.  These  are  parsed  according  to  the  phoncode  grammar.  The [48{ [6{  alternative representation is used, as described in section 7.3.8. [6{  [48{ [6{  0augh => o: a: 0air => eE 1eigh => eI aI 0aer => e: 0ough => o: aU u E EU 0are => eE 1igh => aI 0ar => a: r E 1eau => EU ju 0ear => a: e: IE eE 0tch => ch 0ere => IE 1cs => ks 0re => e: r E 0sc => s 0er => e: r E 1dj => dz 0ier => IE 1bb => b 0ir => e: E r 1cc => k ks s 0our => o: 1ck => k 0oor => o: 1dd => d 0ore => o: 1ff => f th tv 0or => o: e: r E 1gg => g 0ure => e: r 1ll => l 0ur => E e: r 1mm => m *au => EU eI O o: 1nn => n *eu => ju 1pp => p *ou => aU 1rr => r *ai => eI eE 0ssi => sh *ie => i aI I IE 1ss => s z zh sh *ee => i IE 1tt => t *ea => i IE eI eE e 1zz => z zh *oi => oI 1ch => k ch sh *ei => i I 1gh => f g 1ae => i eE E eI IE 1ph => f p 1aa => a: 1sh => sh s ch 1ai => eI eE E aI I e 1th => th tv 1au => EU aU o: a: O 1wh => h w 1ee => i IE eI e E 1rh => r 0eu => ju 0eou => E 1oa => EU o: O E aU 1qu => kw 1oo => u U ^ EU o: O aU 0gue => g 1ou => E EU u U ^ aU o: ju 0gu => g 1ay => eI eE aI e I i 0dge => dz 1ey => eI i aI I 0dg => dz 1uy => aI 0ge => dz g 0hoy => oI 0ce => s z 1oy => oI 0ci => s sh 1iy => aI I 0cq => kw 0ye => aI I 0ayor => eE 0yoo => ju 0oar => e: o: 0you => ju Figure B-1: Grapheme-Phoneme Correspondences: Grammar used in Phoncode Program [6{  [48{ [6{  0yo => ju 0ks => ks 0ao => O 0lf => f v 0ei => i IE aI I eE eI 0lm => m 0ea => a: i IE e e: eI eE E 0lk => k 0eo => IE i 0ld => d 0ia => aI eE 0an => n 0ie => i IE aI I eE u 0en => n 0iu => m ?? 0on => n 0oi => oI u 0se => s z 0oe => EU u ^ 0mb => m 0ua => O 0nm => m 0ui => u ju oI I 0ng => ng 0ue => u ju 0si => sh zh 0uo => ju EU aU 0sw => s 0aw => o: 0ti => ch sh zh 0ouw => o: 0ct => ch 0iew => ju 0wr => r 0ew => u ju EU 1a =>eI eE ae a: e e: E O o: ^ I 0ow => EU aU o: 1e => i IE e e: E I eI eE ae 0uw => u ju w 1i => e: E aI I y i e ^ *y => aI I 1o=>e: E EU o: u U ^ O I aU ju w *a => eI eE ae a: I E aI e 1u => e: E U ju ^ w u I e *e => i IE e e: eE E 1b => b *i => i aI I e E 1c => k s sh *o => EU o: O ^ u oI 1d => d dz t *u => u U ju ^ o: E ae 1f => f v th tv 0ps => s 1g => g zh dz k 0bt => t 1h => h 0ct => k 1l => l 0dt => d 1m => m 0al => o: 1n => n ng m 0el => l 1r => r e: E 0il => l 1s => s sh z zh 0ul => l 1t => t ch sh d th 0le => l 1p => p 0ed => t d 1q => kw k 0de => d 1j => dz 0es => z zh s 1k => k 0ve => v f 1v => v 0gn => n 1w => w 0gi => dz 1x => g k ks s z zh 0kn => n 1y => aI I y i ju 0kw => kw 1z => z zh s sh [48{ [6{Figure B-1, continued [6{  [48{ [6{  add ae d hello h e l EU adjust ae dz ^ s t help h e l p adrift E d r I f t helped h e l p d adventure ae d v e n ch E kind k aI n d adventure ae d v e n ch E r kingston k I ng s t E n after a: f t E r kitchen k I ch E n after a: f t E knee n i again E g eI n knees n i z against E g eI n s t knew n ju age eI dz knife n aI f ago E g EU knight n aI t ahead E h e d knock n O k aims eI m s knocked n O k d air eE r know n EU alan ae l E n night n aI t alex ae l e ks nightmares n aI t m eE z alight E l aI t nightmares n aI t m eE r z all o: l nights n aI t s allowed E l aU d nine n aI n he h i ninety n aI n t I head h e d theory th IE r I headed h e d I d there tv eE r header h e d E these tv i z header h e d E r they tv eI hear h IE thicknesses th I k n E s E z hear h IE r wheel w i l heard h e: d wheels w i l z heard h e: r d when w e n height h aI t where w eE r held h e l d which w I ch while w aI l  Figure B-2: Examples of the phonetically coded dictionary [6{  [48{ [6{  error=nee error=thair node = 1 node = 1 phon = /n/ , next = 2 phon = /th/, next = 3 phon = /ng/, next = 2 phon = /tv/, next = 3 node = 2 node = 2 phon = /eI/, next = 4 node = 3 phon = /i/ , next = 4 phon = /eI/, next = 5 phon = /IE/, next = 4 phon = /eE/, next = 5 node =3 phon = /eE/, next = 6 =knee phon = /e/ , next = 5 phon = /E/ , next = 5 error=nite phon = /aI/, next = 5 node =1 phon = /I/ , next = 5 phon = /n/ , next = 2 node =4 phon = /ng/, next = 2 phon = /e:/, next = 6 node =2 phon = /E/ , next = 6 phon = /i/ , next = 103 phon = /r/ , next = 6 phon = /i/ , next = 3 node =5 phon = /e/ , next = 3 phon = /e:/, next = 6 phon = /e:/, next = 3 phon = /E/ , next = 6 phon = /E/ , next = 3 phon = /r/ , next = 6 phon = /aI/, next = 3 =there phon = /aI/, next = 103 phon = /I/ , next = 3 error=aymz phon = /I/ , next = 103 node =1 phon = /y/ , next = 3 phon = /eI/, next = 3 node =3 phon = /eE/, next = 3 phon = /ch/, next = 4 phon = /e/ , next = 3 phon = /sh/, next = 4 phon = /aI/, next = 3 phon = /t/ , next = 4 phon = /I/ , next = 3 node =4 node =2 phon = /eI/, next = 5 node =3 phon = /eE/, next = 5 phon = /m/ , next = 4 phon = /ae/, next = 5 node =4 phon = /i/ , next = 5 phon = /s/ , next = 5 phon = /IE/, next = 5 phon = /sh/, next = 5 phon = /e/ , next = 5 phon = /z/ , next = 5 phon = /e:/, next = 5 phon = /zh/, next = 5 phon = /E/ , next = 5 =aims phon = /I/ , next = 5 =knight =night Figure B-3: Examples parses of words according to phoncode grammar: alternative representation [6{   APPENDIX C CORPUS OF ERRORS - BOTH PILOT STUDIES  PILOT GROUP 1 - ERRORS GARY shipwright shipright heard herd design desin scraping sraping rugby ruby scrape srap live livea scrape scape upon apone scratches scaratches miss mis scratches scaretches fifty fity panes pains ninety ninty JOHN hotel hotle money monye lovely lovey coming comeing jack jacke stair stare russell rusul mug mag portobello portobellw surprise supris wreck reck pulled pulld rock roack knife knif computer compuoter squeak squaek computer compouter scream skraem turtle turtul scream skream funny funy there thiar cover kuver turned ternd board bord curtain crtane type tipe wiggled wigule built bilt change cange killed kild went weat nightmares nightmars seen sean very verey blood blode always alwas came cam MARK won one witches whitchs mr mir witches whitghs scott scot witches witchs goals gouls were where left lifet spells spels john jonh needles nedils gary garry memories memorys stairs stears memories memries where wear threw through [6{  [48{ [6{  sheet shet a are numbers numders burned berned kept cept change gh kept kapt against agenst kept kepit diving biving artificial artifishal other athrer wrote nrote other ather wrote krote not knot goodbye gooddy goodbye goodby LEON takes takse quarry qorie fights fithse middleton midleton steals steels began bigan plates platse talking talkin does dose fool full bucket buket ghost gohst fights fihgts there thier turtle turtel wearing warin machine machein skirt skurt machine machien hey hay can cane about abuot memories memoris legion legon lonely lonly hullo hulo NICHOLAS fight fihgt turtle tertle paw po heard haerd paw pau department departmemt take taik sounds souns hurt hut stairs stares motorway mototorway when wen change caing nana nanana change chnge lost loast nicky nicy cousin coun department deppartment month munth and andt cousin cousen logo loggo fireplace fierplase artificial artifical nicholas nichoias we wer watson wautsan learnt lernt taking takeing about abowt photos photoso fishes fishs CHARLES commercial commrs goodbye goobay commercial commcil buttons buttns charles chales start sart street steet letters lettes called colde there ther called collde castle castl school shool that thet i iy haunted hoted guinea giney says ses busby busbes night nairt university ynusty haunt hont [6{  [48{ [6{  there ther you yo that thet hear her can came noises noss draw droy front frunt picture picher the whe push posh can came some sum train tran buttons butns going golng like lake through thro drop drot came cane board bord change chage charles chares blows bols recall tecall its is turtle turle horn hon change calde horn hone called calde ghost gost some somb hear haes some sume noise nose goodbye gooboy that ther goodbye goodbay ghost ghoet SUSAN easter eastr make msea road rood came come plays pays then the plays pilas get cet peach paech dinner dinnrer edinburgh ediburgh time the backgreen daccgreen memories memoies change chenge turtle turle new neea get cedt had hat change chage shot shat watching waching join john television tahgfring draw john tv talhfi make mosea turnover turofr horror horey PILOT GROUP 2 - ERRORS FR brown broun crowns crouns hair hera silver isilver hair hare looking loking clothes cloths saw sore eyes irs saw sour eyes ias saw souw eyes eys fingers finges head hard skeleton scelleten head herd skeleton scelletn head haid skeleton skelleten shoes shous front frount shoes shoues screamed scremd chipped chiped screamed screemed two to ghosts gosted [6{  [48{ [6{  two tow ghosts ghosted years yaers ghosts gostst trousers truusesrs house howse goodbye goodby opened opend goodbye goodbay bodies bodys goodbye goodbey terry tery island ilend said sead forest forist blood bloud field filed where warh mountains mountans where werh treasure tresher found fond treasure treasere touched tuched diamonds dimens touched tutched jewels jouls suddenly suddely bodies bodes treasure jouls blood blod through thow computer compter screamed screemed procedure prseeger touched tutched chemicals cemicls using uesing photo poto magazine magezean scored scord week weeke jewels treser pictures picters machine machien pictures pikters went wen ribbons ribons through troug programmed programed through trough procedure prseeger through throught commands comands through throgt piece pees through throght piece peces murdered murderd piece piese there ther piece peesc blood plood shapes shaps running runing there thier of fo chair chive done dun sofa sofer wembley wembly plans plandes players playes about ubout scottish scotish showed sods team teame showed shode macleish maleish showed shodes england ingling showed sodes england ingland took toke scored scord took tooke nicholas nicolas work worke write rite machine machne labour laber camera camer using yoosing picture picter does dus how howe magazine magzine photo foto magazine magzeen put pit magazine magazien develop divelit computers compyooter wyse wizes turtle turtel mine mini shell sell chemical cemilkol controls contrals chemical cemikle wheels weels [6{  [48{ [6{  DV years yerse want wont blue blie going gon eyes liss interview intovue eyes isse interview interuien brown bloum interview intervien brown broum interview intervie brown broun soldiers soildde brown brouum turtle tultlue brown blounm plastic plasdid hair hear plastic plastid hair haer plastic plastad wearing waring plastic plaskid jeans jen plastic plaiked bye bi wire wiure island illing does does island iland pictures picte of over pictures pieces of ove pictures pictce of ov help hlep of ovre stairs stared near neer stairs stare near mear down domne buried berayd down dome buried beray down dame ghost goss picture pictur house houes picture picte when wen picture pictee terry tery could cood darren darin could cold built bulut want wont cup cap gold good said sed working woking kenny cenay working wuking kenny kenne bit bid kenny kenye talk tock dalgleish dugle drill drule dalgleish duglesh more mor dalgleish dalglelsh david davd because becose francis farasis goals gois picture pichur should shood photo fot have uve photo fotot for of photo front goodbye boodbye white withe score scorre white wite scotland scoltand with whith magazine magssen francis franses magazine magsen knight night magazine magen thank thack years yeas ghost gol eyes eye house houes brown brom built buld hair hard little littie socks sock because becoes near her score scor [6{  [48{ [6{  treasure teresur should shod buried berde stairs star have hath plastic palsick lake lack want wont TE weight wait hops hop stone ston ?jrle jrle trousers troosers want wont tie tiy write right brown boron downing bownen brown bron downing downen brown broan magazine magasebn blue blule conservative kunsevrter colours clors conservative cunjnc goodbye goodbiy conservative sevter traps trips conservative konsevtatv near nerer thatcher thach near nere thatcher thacher shipwreck shipreg mrs missis gold golb use uoser gold goib use uose nearer nerer draw braw david daivd make maek put pot instructions instructins there ther instructions insrushn back dack turtle turtl watch woch plastic plasek line lifn are ar line lin these theser hotel honteb these theres hotel hote called colled put pot found foond through thro cashline caskline through thr cashline cashlin ghost gost bare bair ghost gosts of over came gam of off came come house hoses out ot house howes called golld house hos called cocled where were called colled work wrk called colld line lin david daved any eney david davet any eny come conn any ene come cone tools tols police polce tools toles police plec the ther were wer metal metel puzzled puzzel metal meetel seen cn were wer seen cen very vere head hoied tough thufh skeleton skeletn would wob [6{  [48{ [6{  francis franse if ifh motor mothir took toik motor moterdf dark barck motor moterd we wie bike dike had thad wheel weel making maken rock raock developed bvelupb drive brive back dack dangerously bandrie terminal termel dangerously bangersly terminal termer dangerously dangersly david davet ireland irlnd david daved ?cbigl cbigl just tust done doo walked workt bunny dunny took tike bunny bune our or bunny buny photo foto shoes shose police plesa shows shos put poot trousers trosers through thro brown broen motorbike motrbike hear her skid skib what whot bunny buney line lin dangerously bangriele ghost gost conservative gusertr skeleton skeletn turtle totel david davit plastic plastec come cume photo puot DR ten toen stadium stadeum birthday briday scotland scottland birthday brithday people peppla two to brazil bransl have haft brazil brasur have half ?par par trousers tothers ?gondchanken gondchankn black brack turtle turned shirt shurt turtle trener light lite turtle turend yellow yellew of off are ar make mark goodbye goodbiy with which then then with whith island inand instructions inchins island isand instructions incruns pond poond instructions chuns the then instructions intrunctons cross sross instructions instructons swamps swomps instructions instrutions water warer instructions inchuns around arond instructions instrunchins crown cwon instructions instruncton crown cwuon picture ping check pellrs picture picksher are ar picture pictshere [6{  [48{ [6{  packed park picture pishur packed parck picture picher packed par picture picter packed part robot romdt packed pakt robot rodert england enlland robot roder england aingland robot romdert won wun robot rodet won win kitchen kitshen strachan stacking cook ckook strachan cracking cook crook nicholas nickris dead beb nicholas nickis dead ded unlucky unluck has his unlucky unlunck door boor lucky luch hall hooll took toog dog bog stadium stamum ghost gost stadium stamun carpet kapit GR telephone telephon intelligence intelegent used yosed intelligence intellegence pictures pitures university univesty sharples shovples try trie teacher teatcher computer conputer teacher taecher there their teacher tatcher wires wiers university universta boxes boxs called could even eve kingston kinston who how were where uses yous centres centers language langue their there about aboat they the perq perk tutor tuter wire wier sum sume microchip mirchip goes gos used yoused by buy puck pirck screen scren pattern parteren pressing preason pattern pateren straight strat write wriet able abul alphabet alphapet answered answedd commands camands answered answerd quit quite machine machene a and artificial artfichel put pit any ena DI models modles controlled controled smaller smaler operate opperate their there by buy millimetres millimeteres typing typeing centimetres centimeeters check checkk centimetres centimeters stick stik [6{  [48{ [6{  needed neaded specifications spesifications instrument instramen specifications spec designed designned perq perk motors moters you yoy which whish terminal ternimal MA factories factuares putting puting factories factures wither ether suitable sutable easier easyer what wat moving moveing description discription which whitch spraying spairing kind kined spraying spaing appearance appaerance welding wealding been bean unpleasant unplesant instructions instrutions hoped hopped procedure proseador which whilch perq purk which whick perq pirck boring borring perq purq boring borning using useing receive resive pencil pensil receive receiv paddle padle receive resiev somewhere somewhare alternatives alteration thicknesses thiknesses alterations alternations picture pickture alterations alternion else els order oder making makeing ST does dose tune thune buggy bugy procedures prosegers buggy bugi procedures prgrame computer commputer build biuld mathematics mathamatics computer commputers technic tecnic you yo government goverment add asdd motors mottors spaces spaceses controlling conttrolling patterns pateerns peter peper patterns pattrens turtle tutle copy coppy using useing another anther commands comands three theree numeric numerical been beny angle angel coming comming draw drow here herar programmes progames here heer so sow possible posibale have huve possible posiblle instructions instruckshons possible possabile tune chun perq perc [6{  [48{ [6{  REFERENCES [48{ [6{  (Alberga, 1967)  Alberga, C.N. String Similarity and Misspellings. Communications of the ACM 10(5):302-313, May, 1967.  (Albrow, 1974)  Albrow, K. The Nature of the Writing System and its Relation to  Speech. In Wade, B. and Wedell, K. (editors), Spelling: Task and  Learner, . University of Birmingham, Birmingham, 1974.  (Allen, 1981)  Allen, J. Linguistic Based Algorithms Offer Practical Text-to-Speech  Systems. Speech Technology 1(1), fall, 1981.  (Atkinson, 1974) Atkinson, R.C. Teaching Children to Read Using a Computer. American Psychologist 29:169-178, 1974.  (Attisha and Yazdani, 1983) Attisha, M. and Yazdani, M. A Micro-Computer Based Tutor for Teaching Arithmetic  Skills. Instructional Science 12:333-342, 1983.  (Atwell, 1983)  Atwell, E. Constituent-likelihood Grammars. ICAME News: newsletter of the International Computer Ar-  chive of Modern English 7:34-67, May, 1983.  (Backhouse, 1979) Backhouse, R. The Syntax of Programming Languages: Theory and Practice. Prentice-Hall International, London, 1979.  (Baker, 1980)  Baker, R.G. Orthographic Awareness. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  3,pages 51-68. Academic Press, London, 1980.  (Baron, 1977)  Baron, J. Mechanisms for Pronouncing Printed Words: Use and Acquisi-  tion. In Laberge, D., Samuels, S.J. (editor), Basic processes in  reading. Perception and Comprehension, chapter 6,pages  175-216. Lawrence Erlbaum, Hillsdale, NJ., 1977.  (Barron, 1980)  Barron, R.W. Visual and Phonological Strategies in Reading and Spelling. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  9,pages 195-213. Academic Press, London, 1980. [6{  [48{ [6{  (Bennett, 1967) Bennett, D.M. New Methods and Materials in Spelling. Australian Council for Educational Research. Dominion Press,  Victoria, Australia, 1967.  (Blair, 1960)  Blair, C.R. A Program for Correcting Spelling Errors. Information and Control 3:60-67, 1960.  (Block, 1979)  Block, K.K. Cognitive Theory, CAI and Spelling Improvement. Journal of Computer-Based Instruction 5(4):86-95, May, 1979.  (Brown and VanLehn, 1980) Brown, J.S. and VanLehn, K. Repair Theory: A Generative Theory of Bugs in Procedural  Skills. Cognitive Science 4:379-426, 1980.  (Bruce and Rubin, 1984) Bruce, B. and Rubin, A. QUILL Project. In International Conference on Education and New Infor-  mation Technologies, . Center for Educational Research  and Innovation, Paris, 1984. Summary.  (Brueckner and Bond, 1955) Brueckner, L.J. and Bond, G.L. Diagnosis and Treatment of Spelling Difficulties. Appleton-Century-Crofts, Inc., New York, 1955, pages  346-380,chapter 11.  (Bryant and Bradley, 1980) Bryant, P.E. and Bradley, L. Why Children sometimes Write Words which they do not  Read. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  16,pages 355-370. Academic Press, London, 1980.  (Burton, 1982)  Burton, R.R. DEBUGGY: Diagnosis of Errors in Basic Mathematical Skills. In Sleeman, D. and Brown, J.S. (editors), Intelligent Tutoring  Systems, . Academic Press, London, 1982.  (Cahen et al, 1971) Cahen, L.S., Craun, M.J., and Johnson, S.K. Spelling Difficulty - a Survey of the Research. Review of Educational Research 41(4):281-301, 1971.  (Candy, 1982)  Candy, L. A Study in the Use of a Computer as an Aid to English  Teaching. International Journal of Man-Machine Studies 16:333-339,  1982. [6{  [48{ [6{  (Cassidy, 1984)  Cassidy, S. The Use of a Speech Synthesizer in the Teaching of Read-  ing. Master's thesis, Department of Artificial Intelligence, Sept.,  1984.  (Chomsky and Halle, 1968) Chomsky, N. and Halle, M. The Sound Pattern of English. Harper and Row, New York, 1968.  (Ciarcia, 1982)  Ciarcia, S. Build the Microvox Text-to-Speech Synthesizer. Part 2:  Software. BYTE :40-64, October, 1982.  (Clarke, 1982)  Clarke, M. Talk presented at U.K.R.A. conference, and personal com-  munication.  (Cohen, 1980)  Cohen, G. Reading and Searching for Spelling Errors. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  7,pages 135-155. Academic Press, London, 1980.  (Collins, 1982)  Collins, A. Teaching Reading and Writing with Personal Computers. 1982. Written under contract for the National Institute of  Educational Reading Synthesis Project.  (Cornew, 1968)  Cornew, R.W. A Statistical Method for Spelling Correction. Information and Control 12, 1968.  (Cumming et al, 1984) Cumming, G.D., Richards, T. and Woodhouse, D. Use of Computers in Teaching Beginning Reading. In International Conference on Education and New Infor-  mation Technologies, . Center for Educational Research  and Innovation, Paris, 1984. Summary.  (Damerau, 1964) Damerau, F. A Technique for Computer Detection and Correction of  Spelling Errors. Communications of the ACM 7(3):171-176, March, 1964.  (Davidson, 1962) Davidson, L. Retrieval of Misspelled Names in an Airlines Passenger Record  System. Communications of the ACM 5:169-171, March, 1962. [6{  [48{ [6{  (Desberg, 1980) Desberg, P., Elliott, D.E. and Marsh, G. American Black English and Spelling. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  4,pages 69-82. Academic Press, London, 1980.  (Durham et al, 1983) Durham, I., Lamb, D.A., Saxe, J.B. Spelling Correction in User Interfaces. Communications of the ACM 26(10):764-773, October, 1983.  (Ehri, 1980)  Ehri, L.C. The Development of Orthographic Images. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  14,pages 311-338. Academic Press, London, 1980.  (Ellis, 1981)  Ellis, N.C. Project Application. Personal communication.  (Ellis and Miles, 1977) Ellis, N.C., Miles, T.R. Dyslexia as a Limitation in the Ability to Process Infor-  mation. Bulletin of the Orton Society 27:72-81, 1977.  (Ellis and Miles, 1978a) Ellis, N.C., Miles, T.R. Visual Information Processing as a Determinant of Reading  Speed. Research in Reading 1(2):108-120, 1978.  (Ellis and Miles, 1978b) Ellis, N.G., Miles, T.R. Visual Information Processing in Dyslexic Children. In Gruneberg, Morris and Sykes (editor), Practical Aspects  of Memory, pages 561-569. Academic Press, 1978.  (Ellovitz et al, 1976) Ellovitz, H.S., Johnson, R.W., McHugh, A., Shore, J.E. Automatic Translation of English Text to Phonetics by Means  of Letter to Sound Rules. IEEE Transactions on Acoustics, Speech and Signal Processing  24:446, 1976.  (Farnham-Diggory and Simon, 1975) Farnham-Diggory, K. and Simon, H.A. Retention of Visually Presented Information in Children's  Spelling. Memory and Cognition 3(6):599-608, 1975.  (Fass, 1983)  Fass, D. C. The Design of a Spelling Corrector Using Context. Master's thesis, Dept. of Computer Science, University of  Essex, April, 1983. [6{  [48{ [6{  (Fass, 1984)  Fass, D. Personal communication:Ph.D. thesis in progress based on  M.Sc. work.  (Fass and Wilks, 1983) Fass, D., Wilks, Y. Preference Semantics, Ill-formedness, and Metaphor. American Journal of Computational Linguistics 9(3-4), July-  December, 1983.  (Fiddy, 1982)  Fiddy, P. Microcomputers: Allies to Infant Teachers. 1982. Unpublished Paper.  (Fremer and Anastasio, 1969) Fremer, J. and Anastasio, E.J. Computer Assisted Item Writing - I: Spelling Items. Journal of Educational Measurement 6(2):69-74, 1969.  (Frith, 1978) Frith, U. Spelling Difficulties. Journal of Child Psychology and Psychiatry 19(3):279-285,  July, 1978.  (Frith, 1980a)  Frith, U. (editor). Cognitive Processes in Spelling. Academic Press, London, 1980.  (Frith, 1980b)  Frith, U. Unexpected Spelling Problems. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  22,pages 495-515. Academic Press, London, 1980.  (Galli and Yamada, 1968) Galli, E.J., Yamada, H.M. Experimental Studies of Computer-Assisted Correction of  Orthographic Text. IEEE Transactions on Engineering Writing and Speech  11(2):75-84, 1968.  (Gentry, 1978)  Gentry, J.R. Early Spelling Strategies. The Elementary School Journal 79(2):88-92, November, 1978.  (Gibson, 1969)  Gibson, S.K. Computer Aided Construction of Categorised Spelling Tests. ERIC: ED 039 226. University of Washington, Bureau of Testing, Report June  1969. [6{  [48{ [6{  (Grocke, 1982)  Grocke, M.A. Interactive Development of Reading Skills in an Educational  Clinic. 1982. Paper Presented at 18th Nat. Conf. of Australian Group for  the Scientific Study of Mental Deficiency.  (Groff, 1977)  Groff, P. Phonics, How and Why. General Learning Press, New Jersey, U.S.A., 1977.  (Guthrie and Siefert, 1977) Guthrie, J.T., Siefert, M. Letter-Sound Complexity in Learning to Identify Words. Journal of Educational Psychology 69(6):686-696, 1977.  (Hammill, 1975)  Hammill, D.D., Noone, J. Improving Spelling Skills. In Hammill and Bartell (editor), Teaching Children with  Learning and Behaviour Problems, chapter 4. Allyn and  Bacon Inc., Boston, 1975.  (Hanna et al, 1966) Hanna, P.R., Hanna, J.S., Hodges, R.E., Rudorf, E.H. Phoneme-Grapheme Correspondences as Cues to Spelling  Improvement. US Office of Education, Washington, 1966.  (Harpin, 1976)  Harpin, W. The Second `R'. Unwin Educational Books, London, 1976.  (Hasselbring and Crossland, 1982) Hasselbring, T.S. and Crossland, C.L. Application of Microcomputer Technology and Spelling Assess-  ment of Learning Disabled Students. Learning Disability Quarterly 5(Winter):80-82, 1982.  (Henderson and Chard, 1980) Henderson, L. and Chard, J. The Reader's Implicit Knowledge of Orthographic Structure. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  5,pages 85-116. Academic Press, London, 1980.  (Hicks, 1980)  Hicks, C. Modality Preference and the Teaching of Reading and Spell-  ing to Dyslexic Children. British Educational Research Journal 6(2), 1980.  (Hildreth, 1955) Hildreth, G. Entry on Spelling. In Encyclopedia of Education, pages 387. MacMillan and Free  Press, 1955. [6{  [48{ [6{  (Horn, 1969)  Horn, E. Entry on Spelling. In American Educational Research Association (editor),  Encyclopedia of Educational Research, pages 1282-1293.  MacMillan Co., London, 1969.  (Hornsby and Shear, 1978) Hornsby, B. and Shear, F. Alpha to Omega: The A-Z of Teaching Reading, Writing and  Spelling. Heinemann Educational Books, London, 1978. Second Edition.  (Howe, 1979)  Howe, J.A.M. Some roles for the computer in special education. DAI Research Report 126, Department of Artificial Intel-  ligence, University of Edinburgh, 1979.  (Howe et al, 1978) Howe, J.A.M., Beattie, A., Cassels, F., Johnson, J. and Ander- son, A. Teaching Handicapped Children to Read in a Computer-Based  Learning Environment. DAI Research Report 57, Department of Artificial Intel-  ligence, University of Edinburgh, 1978.  (Hughes, 1973)  Hughes, J.M. Phonics and the Teaching of Reading. Evan Brothers Ltd., London, 1973.  (Jung, 1980)  Jung, U. Reading, Writing and Phonology in Modern Foreign-Language  Teaching. In Felix, S.W. (editor), Second Language Development. Trends  and Issues, pages 249-263. Tubingen, 1980.  (Leveux, 1977)  Leveux, S.A. Computer Assisted Spelling and Arithmetic. Computer Education 26:25, June, 1977.  (Lewis, 1980)  Lewis, M. Improving SOLO's User-Interface: an Empirical Study of User  Behaviour and a Proposal for Cost Effective  Enhancements. Technical Report, The Open University, Milton, Keynes, 1980. Unpublished draft.  (Macdonald, Frase et al., 1982) Macdonald, N.H., Frase, L.T., Gingrich, P.S., and Keenan, S.A. The Writers Workbench: Computer Aids for Text Analysis. IEEE Transactions on Communications , January, 1982. Special Issue on Communications in the Automated Office. [6{  [48{ [6{  (MacKay, Thompson and Schaub, 1978) MacKay, D. Thompson, B. and Schaub, P. Breakthrough to Literacy Teacher's Manual Illustrated edition, London, 1978.  (Malmquist, l973) Malmquist, E.J. Retardation. In Staiger,R.C. (editor), The Teaching of Reading, chapter 6.  Ginn & Co., Unesco, Paris, l973.  (Marsh et al., 1980) Marsh, G., Friedman, M., Welch, V. and Desberg, P. The Development of Strategies in Spelling. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  15,pages 339-353. Academic Press, London, 1980.  (Masters, 1927)  Masters, H.V. A Study of Spelling Errors. PhD thesis, University of Iowa, 1927. Unpublished.  (McMahon et al, 1978) Mcmahon, L.E., Cherry, L.L., Morris, R. Statistical Text Processing. Bell System Technical Journal 57(6):2137-2154, July-August,  1978.  (Miles and Wheeler, 1974) Miles, T.R., Wheeler, T.J. Towards a New Theory of Dyslexia. Dyslexia Review 10:9-11, 1974.  (Mitton, 1984a)  Mitton, R. Personal Communication.  (Mitton, 1984b) Mitton, R. A Corpus of Misspellings Analysed by Simple Error-Types and  by Soundex Codes. Research Report JRM/06/84, Dept. of Computer Science,  Birkbeck College, University of London, 1984.  (Mor and Fraenkel, 1982) Mor, M., Fraenkel, A.S. A Hash Code Method for Detecting and Correcting Spelling  Errors. Communications of the ACM 25(12):935-938, December, 1982.  (Morgan, 1970)  Morgan, H.L. Spelling Correction in Systems Programs. Communications of the ACM 13(2):90-94, 1970.  (Morris-Wilson, 1984) Morris-Wilson, I. English Phonemic Transcription. Basil Blackwell Ltd., Oxford, 1984. [6{  [48{ [6{  (Munnecke, 1980) Munnecke, T. Give your Computer an Ear for Names. BYTE :196-200, May, 1980.  (Naidoo, 1972) Naidoo, S. Specific Dyslexia - the Research Report of the Invalid  Children's Aid Association Word Blind Centre for Dyslexic  Children. Pitman Press, London, 1972.  (Nelson, 1980)  Nelson, H. Analysis of Spelling Errors in Normal and Dyslexic Children. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  21,pages 475-493. Academic Press, London, 1980.  (Nolen, 1980)  Nolen, P. Sound Reasoning in Spelling. The Reading Teacher 33(5):538-543, Feb., 1980.  (O'Shea and Young, 1978) O'Shea, T. and Young, R.M. A Production Rule Account of Error's in Children's Subtrac-  tion. In Proceedings of the AISB-78 Conference on Artificial In-  telligence, Hamburg, pages 229-237. The Society for the  Study of Artificial Intelligence and Simulation of Be-  haviour, 1978.  (Omond, 1977)  Omond, R.A. A Spelling Correction System (the Speller). Undergraduate Project Report, Department of Artificial  Itelligence, University of Edinburgh, 1977.  (Otto et al, 1973) Otto, W., McMenemy, R.A., Smith, D.J. Spelling. In Corrective and Remedial Spelling, chapter 10. Houghton  Mifflin, 1973.  (Pain, 1980)  Pain, H.G. Analysis of Errors in Spelling. DAI Working Paper 61, Department of Artificial Intelligence,  University of Edinburgh, 1980.  (Pavlidis, 1979)  Pavlidis, G.T. How can Dyslexia be Objectively Diagnosed? Reading 13(3):3-15, December, 1979.  (Peters, 1974)  Peters, M.L. The Significance of Spelling Miscues. In Wade, B. and Wedell, K. (editors), Spelling: Task and  Learner, pages 56-60. University of Birmingham, Birmin-  gham, 1974. [6{  [48{ [6{  (Peters, 1975)  Peters, M.L. Diagnostic and Remedial Spelling Manual London, 1975.  (Peterson, 1980a) Peterson, J.L. Computer Programs for Detecting and Correcting Spelling  Errors. Communications of the ACM 23(12):676-687, December, 1980.  (Peterson, 1980b) Peterson, J.L. Lecture Notes in Computer Science. Volume 96: Computer  Programs for Spelling Correction: an experiment in  program design. Springer Verlag, 1980.  (Pollock, 1982)  Pollock, J.J. Spelling Error Detection and Correction by Computer: some  notes and a bibliography. Journal of Documentation 38(4):282-291, December, 1982.  (Pollock and Zamora, 1984) Pollock, J.J., Zamora, A. Automatic Spelling Correction in Scientific and Scholarly  Text. Communications of the ACM 27(4):358-368, April, 1984.  (Prinz and Nelson, 1984) Prinz, P.M. and Nelson, K.E. Child-Adult-Teacher Interactive Method for Teaching Reading  and Writing to Young Deaf Children. In International Conference on Education and New Infor-  mation Technologies, . Center for Educational Research  and Innovation, Paris, 1984. Summary.  (Quinsaat, Levin and Gentner, 1980) Quinsaat, M.G., Levin, J.A. and Gentner, D. A Writer's Assistant: The Use of Personal Computers to  Teach Writing. 1980. Unpublished paper.  (Sharples, 1984) Sharples, M. Cognition, Computers and Creative Writing. PhD thesis, Department of Artificial Intelligence, 1984.  (Simon, 1976)  Simon D.P. Spelling. A Task Analysis. Institutional Science 5:277-302, July, 1976.  (Simon and Simon, 1973) Simon, D.P., Simon, H.A. Alternative Uses of Phonemic Information in Spelling. Review of Educational Research 43:115-137, 1973. [6{  [48{ [6{  (Skousen, 1982) Skousen, R. English Spelling and Phonemic Representation. Visible Language 16(1):28-38, 1982.  (Sloboda, 1980)  Sloboda, J.A. Visual Imagery and Individual Differences. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  11,pages 231-248. Academic Press, London, 1980.  (Smith, P.T., 1980) Smith, P.T. Linguistic Information in Spelling. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  2,pages 33-49. Academic Press, London, 1980.  (Solomon and MacNeill, 1967) Solomon, H. and MacNeill, I. Spelling Ability: A Comparison between Computer Output  based on a Phonemic-Graphemic Algorithm and Actual  Student Performance in Elementary Grades. Research in the Teaching of English 1:157-175, 1967.  (Spache, 1940)  Spache, G. A Critical Analysis of Various Methods of Classifying Spelling  Errors, I. Journal of Educational Psychology 31:111-134, 1940.  (Stevenson, 1984) Stevenson, H.W. Orthography and Reading Disabilities. Journal of Learning Disabilities 17(5), May, 1984.  (Teitelman, 1978) Teitelman, W. Interlisp reference manual Xerox, PARC, California USA., 1978. Chapter 17.  (Tenczar and Golden, 1962) Tenczar, P.J., Golden, W.W. Spelling, Word and Concept Recognition. Technical report CERL-X-35, University of Illinois, October,  1962.  (Tenney, 1980)  Tenney, Y.J. Visual Factors in Spelling. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  10,pages 215-229. Academic Press, London, 1980.  (Terrell, 1984)  Terell, C.D. Remedial Reading: CAL Programs and Speech Generation. 1984. Draft, Unpublished Paper. [6{  [48{ [6{  (Valtin, 1978)  Valtin, R. Dyslexia: Deficit in Reading or Deficit in Research. Reading Research Quarterly 19(2):201-221, 1978.  (Venezky, 1966) Venezky, R.L. Automatic Spelling to Sound Conversion. In Garvin, P.L. and Spolsky, B. (editors), Computation in  Linguistics, chapter 6. Indiana University Press, 1966.  (Venezky, 1967) Venezky, R.L. English Orthography: its Graphical Structure and its Relation  to Sound. Reading Research Quarterly X(3):75-105, 1967.  (Venezky, 1980) Venezky, R.L. From Webster to Rice to Roosevelt: the formative years  for spelling instruction and spelling reform in the U.S.A. In Frith, U. (editor), Cognitive Processes in Spelling, chapter  1,pages 9-30. Academic Press, London, 1980.  (Wade and Wedell, 1974) Wade, B. and Wedell, K. Educational Review Occasional Publications. Volume 5:  Spelling: Task and Learner. University of Birmingham, Birmingham, 1974.  (Wagner and Fisher, 1974) Wagner, R.A. and Fisher, M.J. The String-to-String Correction Problem. Journal of the ACM 21(1):168-173, January, 1974.  (Whiting and Jarrico, 1980) Whiting, S.A. and Jarrico, S. Spelling Patterns of Normal Readers. Journal of Learning Disabilities 13(1), Jan, 1980.  (Wight-Boycott, 1977) Wight-Boycott, V. Fun and First Aid for Weak Spellers. Remedial Education :100-103, 1977. Cambridge Reading Project.  (Wilby, 1980)  Wilby, J.F. Jack Straw Reading Project. Computer Education :15-17, 1980.  (Winograd, 1983) Winograd, T. Language as a Cognitive Process: Syntax. Addison-Wesley, 1983.  (Yannakoudakis and Fawthrop, 1983a) Yannakoudakis, E.J. and Fawthrop, D. The Rules of Spelling Errors. Information Processing and Management 19(2):87-99, 1983. [6{  [48{ [6{  (Yannakoudakis and Fawthrop, 1983b) Yannakoudakis, E.J. and Fawthrop, D. An Intelligent Spelling Error Corrector. Information Processing and Management 19(2):101-108, 1983.  (Zamora, Pollock and Zamora, 1981) Zamora, E.M., Pollock, J. and Zamora, A. The Use of Trigram Analysis for Spelling Error Detection. Information Processing and Management 17(6):305-316, 1981.  (Zinn, 1978)  Zinn, K.L. Speak and Spell Spelling B. Creative Computing :60-61, Sept/Oct, 1978. [6{  TABLE OF CONTENTS  1. Introduction  1 [48{ [6{  1.1. Children  with  learning  difficulties  in  spell- 1  ing: population and problem  1.2. Outline of the research 3  1.3. Questions addressed in this thesis 4  1.4. Plan of the thesis 5 [48{ [6{  2. Review of the Spelling Literature  8 [48{ [6{  2.1. Introduction 8  2.2. English Spelling 8  2.3. Cognitive  theories  of  spelling  and  spelling 15  disability 2.3.1. Reading and Spelling Difficulties 20  2.4. Spelling errors 27  2.4.1. Spelling  test  and  error  classification 28  schemes 2.5. The Teaching of Spelling 37  2.5.1. Remedial Methods 39  2.5.2. Using Computers in Teaching Spelling 41  2.6. Computers and Writing 45 [48{ [6{  3. Review of the Computing Literature 47 [48{ [6{  3.1. Introduction 47  3.2. Detection v. Correction 47  3.2.1. Applications 47  3.2.2. Modes of Use - Interactive Programs 48  3.2.3. Use of context: syntax and semantics 49  3.3. Error Detection 52  3.3.1. Digram and trigram frequencies 52  3.3.2. Dictionary look-up 52  3.3.3. Dictionary size 53  3.3.4. Representation and search 54  3.3.5. What is a word? 55  3.3.6. Dealing with affixes 57  3.4. Error Correction 58  3.4.1. Previous  errors  and  dictionaries  of  com- 58  mon misspellings 3.4.2. Matching substrings 59  3.4.3. Abbreviations 59  3.4.4. Measures of string similarity 60  3.4.5. Editing rules 62  3.4.6. Combined approaches 63  3.4.7. String to string repair 65  3.5. Summary 68 [6{  [48{ [6{  4. Educational and technical constraints of the correction programs  69 [48{ [6{  4.1. Introduction 69  4.2. Theory 69  4.3. Development  of  the  error  classification  scheme 72  and its relation to the correction programs  4.3.1. The children studied 72  4.3.2. The error classification scheme 73  4.3.3. Relating the spelling correction programs 77  to the classification scheme  4.4. Program Design Constraints: Educational 79  4.5. Program design constraints: technical 81  4.6. A summary of the overall requirements 84  4.7. Failure  of  existing  programs  to  satisfy  the 85  requirements [48{ [6{  5. Design and use of a computer program to incorporate the editcost  91  and phoncode correctors [48{ [6{5.1. Introduction 91  5.2. Example of a session 92  5.3. Dictionaries 101  5.3.1. Size and content 101  5.3.2. Dictionary structure 102  5.4. Definition of 'a word' and affixes 102  5.5. Error Detection 104  5.6. Error Correction 104  5.6.1. Syntax 104  5.6.2. Semantics 106  5.7. The editcost program 106  5.8. The phoncode program 107  5.9. Other facilities 108  5.9.1. The lookup facility 108  5.9.2. The addword facility 109  5.10. Relating the design to the requirements 109 [48{ [6{  6. Testing assumptions about the use of the program  111 [48{ [6{  6.1. Introduction 111  6.2. Pilot Study 1 112  6.2.1. Introduction 112  6.2.2. Method 113  6.2.3. Results 116  6.2.4. Discussion 118  6.3. Pilot Study 2 119  6.3.1. Introduction 119  6.3.2. Method 120  6.3.3. Results 123  6.3.4. Discussion 128  6.4. Summary of results from the two pilot studies 130 [48{ [6{  7. Detail of the editcost and phoncode programs  131 [48{ [6{  7.1. Introduction 131  7.2. Calculating  the  minimum  cost  repair:  the  edit- 131  cost program 7.2.1. General overview 131  7.2.2. Shortlisting candidates from the diction- 132  ary: 'shortlist' [6{  [48{ [6{  7.2.3. The editcost algorithm 134  7.2.4. Relation of the children's errors 139  7.2.5. Detail of the editcost program 142  7.3. Phonemic coding of words: the phoncode program 149  7.3.1. General overview 149  7.3.2. Related work 149  7.3.3. Design of the phoncode program 150  7.3.4. Defining the set of phonemes 151  7.3.5. Phoneme-grapheme correspondences 153  7.3.6. Phonemic coding of the dictionary 158  7.3.7. Detail of the phoncode program 160  7.3.8. Segmenting the word 160  7.3.9. Representing the dictionary 165  7.3.10. Matching the word and dictionary 167 [48{ [6{  8. Performance 169 [48{ [6{  8.1. Introduction 169  8.2. Performance of the editcost program 171  8.2.1. Testing editcost in use - Pilot Study 2 171  8.2.2. Testing  on  the  corpus  containing  Pilot 175  Study 1 and Pilot Study 2 errors  8.2.3. Errors  which  the  editcost  program  failed 176  to correct  8.3. Performance of the phoncode program 185  8.3.1. Testing  on  Pilot  Study  1  and  Pilot  Study 185  2 errors 8.3.2. Errors  which  the  phoncode  program  failed 187  to correct  8.4. Results for combined programs 194  8.5. Results for individual children 197  8.6. Testing the programs on independent data 202  8.7. Summary 206 [48{ [6{  9. Conclusions  208 [48{ [6{  9.1. Introduction 208  9.2. Theoretical Questions 208  9.3. Practical Questions 209  9.4. Additional Questions 211  9.5. Criticisms 213  9.6. Proposals for further research 215  9.7. Summary of conclusions 216 [48{ [6{  Appendix A. Editing commands, stories and notes on the children  217 [48{ [6{  Appendix B. Phoncode grammar and examples  239 [48{ [6{  Appendix C. Corpus of errors - both pilot studies  244 [6{  LIST OF FIGURES  Figure 1-1: Samples of children's writing 2  Figure 1-2: Notation for vowel phonemes 6  Figure 1-3: Notation for consonant phonemes 7  Figure 4-1: Sample of population: chronological 74  ages, spelling ages, and reading ages  Figure 4-2: General classes of characters 75  Figure 5-1: Example sections from the dictionary 103  Figure 6-1: Words checked using the correction 126  program  Figure 6-2: Words  selected  when  offered  by  the 127  correction program  Figure 6-3: Child realises the correct word is not 128  presented  Figure 7-1: First character alternatives for 133  shortlisting  Figure 7-2: Graph  representing  edit  operation 136  transformations  Figure 7-3: Costgraph showing the node labelling 137  Figure 7-4: Example  of  the  spelling  corrector  in 140  use Figure 7-5: Pilot group 1: frequency of error 142  types Figure 7-6: Pilot  group  1:  frequency  of  types  of 143  spelling errors  Figure 7-7: Example  of  candidates  and  mininum 144  editcost  Figure 7-8: Representation of 'special cases' 145  Figure 7-9: Weightings assigned to edit functions 146  Figure 7-10: Graph showing example weightings 148  Figure 7-11: Examples  of  use  of  the  phoncode 150  program  Figure 7-12: Representation of vowel phonemes 152  Figure 7-13: Representation of consonant phonemes 153  Figure 7-14: Finite  State  Grammar  representation 161  of 'caught'  Figure 7-15: Alternative representation of 162  'caught'  Figure 7-16: Finite  state  grammar  representation 164  of 'rime': v, c+e  Figure 7-17: Finite  state  grammar  representation 164  of 'rime': v, c, e  Figure 7-18: Representation of 'vc + e' graphemes 165  Figure 7-19: Tree  representation  of  part  of  the 166  phoncode dictionary  Figure 8-1: Editcost in use: outcomes of checking 172 [6{  [48{ [6{  Figure 8-2: Editcost  in  use:  individual  results 173  Correction offered  Figure 8-3: Editcost  in  use:  individual  results 173  Correction not offered  Figure 8-4: Editcost  tested  on  Pilot  Study  1  er- 176  rors Figure 8-5: Editcost  tested  on  Pilot  Study  2  er- 177  rors Figure 8-6: Using  editcost  -  Pilot  Study  2  Errors 178  for which correction not offered  Figure 8-7: Testing  editcost  -  Pilot  Study  1  Er- 178  rors for which correction not offered  Figure 8-8: Testing editcost - Pilot Study 2, 179  group  1  Errors  for  which  correction  not offered  Figure 8-9: Testing editcost - Pilot Study 2, 180  group  2  Errors  for  which  correction  not offered  Figure 8-10: Comparison  of  judge's  corrections 182  with intended corrections - summary  Figure 8-11: Comparison  of  judge's  corrections 183  with intended corrections - Pilot  Study 1  Figure 8-12: Comparison  of  judge's  corrections 183  with intended corrections - Pilot  Study 2  Figure 8-13: Phoncode  tested  on  pilot  study  1  er- 185  rors Figure 8-14: Phoncode  tested  on  pilot  study  2  er- 186  rors Figure 8-15: Comparison of errors corrected by the 188  Phoncode program with those judged to  be 'phonetic' - Pilot Study 1  Figure 8-16: Comparison of errors corrected by the 189  Phoncode program with those judged to  be 'phonetic' - Pilot Study 2  Figure 8-17: Errors judged to be phonetic, but not 191  corrected: PS1 and PS2  Figure 8-18: Comparison of errors corrected by 194  Editcost  and  by  Phoncode  programs  -  Pilot Study 1  Figure 8-19: Comparison of errors corrected by 195  Editcost  and  by  Phoncode  programs  -  Pilot Study 2  Figure 8-20: Testing  of  the  editcost  and  phoncode 203  programs  on  independent  data  -  ex-  cluding repeats  Figure 8-21: Testing  of  the  editcost  and  phoncode 204  programs  on  independent  data  -  in-  cluding repeats  Figure A-1: Summary of Walter commands 218  Figure B-1: Grapheme-Phoneme Correspondences: 240  Grammar used in Phoncode Program  Figure B-2: Examples of the phonetically coded 242  dictionary  Figure B-3: Examples  parses  of  words  according  to 243 [6{  [48{ [6{  phoncode  grammar:  alternative  representation