Implicit alternatives to a stimulus, difficulty of encoding, and schema-plus-correction representation*

Transcription

1 Memry & Cgnitin 97, Vl., N.,60-66 Implicit alternatives t a stimulus, difficulty f encding, and schema-plus-crrectin representatin* GORDONBEAR University fwiscnsin, Madisn, Wiscnsin 706 Garner has hypthesized that a S expsed t a stimulus infers alternatives t it. Data are reviewed which establish a else crretin between the number f implicit alternatives t astimulus and the difficulty f encding that stimulus. This crretin prvides a datum t be expined and suggests that the identificatin f specific implicit alternatives may prvide elues t the encding prcess. Fr dt patterns f a certain kind, it has been suggested that the rtatins and reflectins f a stimulus are its nly alternatives, but a else examinatin f certain data indicates that, fr many f these patterns, the alternatives als inelude ne r rnre ther patterns which differ frm the stimulus nly in the psitin f a single dt and which lcate that dt in a psitin where it is mre predictable frm the ther dts. It is suggested that the ne-dt-different alternatives represent schemas used in schema-plus-crrectin encding. Wende Garner (, Chapter 6, 6) has argued that a S expsed t a stimulus f sme given kind will understand it t be ne f a subset f the stimuli f that kind. The ther members f the subset, accrding t Garner's hypthesis, are implicit alternatives t the stimulus-ther stimuli which the S understands culd have ccurred but did nt. The present paper reprts a review f the data n implicit alternatives, with special attentin t a set f dt patterns which Garner and his assciates have studied intensively. A variety f measures taken n the dt patterns and certain thers prvide evidence fr a else crretin between the number f implicit alternatives t astimulus and the difficulty f encding that stimulus, and attentin is directed t this crretin as an imprtant datum t be expined. The crretin als suggests that an effrt t identify actual alternatives t particur stimuli may prvide sme elues t the encding prcess, and fr the dt patterns in this regard, it has been suggested that the rtatins and reflectins f a pattern are its nly alternatives. A detailed examinatin f certain data indicates, hwever, that the alternatives fr many f the dt patterns inelude ne r mre ther patterns which differ frm the stimulus nly in the psitin f a single dt and which lcate that dt in a psitin where it is mre predictable frm the ther elements f the stimulus. This finding suggests a type f encding generally verlked in current discussins f the prcess-encding as a schema plus a crrectin. NUMBER OF IMPLICIT ALTERNATIVES AND DIFFICULTY OF ENCODING The Dt Patterns The stimuli which Garner and his assciates have studied s intensively are dt patterns f the kind shwn *The authr wishes t thank lhn Flwers fr a helpful critique f an earlier draft f this paper. in Fig. (the numbers within the dts have nt appeared in the stimuli presented t the Ss, f curse). S many data have nw been cllected n these patterns that they cnstitute a virtuay unique cectin f "case histries" in experimental psychlgy and prvide an exceent set f stimuli fr further investigatin f perceptual and cgnitive prcesses. The patterns cnsist f five dts distributed ver the cells f a by matrix. There are 6 patterns f this kind (9Cs), but certain f them are rtatins r reflectins f each ther. Gruping rtatins and reflectins tgether partitins the 6 patterns int mutuay exelusive equivalence sets (prkhvnik, 99), each set cmpsed f thse patterns which are identical t each ther if rtated in ne r mre 90-deg turns, if reflected abut the vertical r the hrizntal axis, r if bth rtated and reflected. Figure dispys a representative pattern frm each equivalence set. The numeral,, r in a set's bel indicates the size f the set, while the letter in the bel distinguishes the set amng the several sets f that size. As the figure indicates, there are sets f Size, sets f Size, and 0 sets f Size. Number fimplicit Alternatives! The number f implicit alternatives fr a given dt pattern has been measured in three ways. Garner and Clement (), first f a, wrked with figures cking the by matrix and thus emplyed nly thse 90 patterns with at least ne dt in each rw and clumn, s that the bundaries f the figures were suggested t the Ss. The researchers reasned that the patterns Ss judge t be simir t a stimulus wuld be representative f thse in its subset f implicit alternatives, and they asked their Ss t srt the 90 patterns int apprximately eight grups f simir figures. The mean size f the grups int which a figure was pced then served t index the number f its implicit alternatives. Handel and Garner (6) ter wrked with figures drawn t inelude the matrix and used a 6 f the 60

2 0.09(I).66(} ) r-- 06 (S). (). () 9.6 () d q h.0 (6). (7) ). (9). (I(» 0. (). (6). ) ). (7) 07.6 <ls) d ) ) - --r--.0(6) 0.99 Cl6) h ) '-_.. (D 0.6 (). () 0. (l Sc.90 (IS) 09. () ie ). () 0. () IMPLICIT ALTERNATIVES TO A STIMULUS 6 a c..- (.0 () 77. (). (7).9 () i.9 (). (9). (). () f ).J.9(9) 0776 (7).) ).6 () 0. (0) b f.99 () 7.76 ().6 () 0.7 (0).7 () 0.6 () c (.9 () 0. () ).6 (0) 06.0 (9) Fig.. Data n five-dt patterns, T the left f each pattern, the bel fr its equivalence set. Belw each pattern n the first line, the mean "gdness" rating f the patterns in its set, as deterrnined by Handel and Garner (6)- = a "gd" pattern, 7 = a "pr" pattern-and the rank f this mean rating, On the secnd line, the rnean f the mean predictability scres fr the patterns in the set and the rank f the rnean, Within each dt, the mean predictability scre fr that dt, cmputed as described in the text, (Frm Bear, 97). patterns. They reasned that the patterns which Ss assciate with astimulus wuld be representative f thse in its subset f implicit alternatives, and fr each f the figures they asked their Ss t draw anther ne "suggested by" it. Garner and Clement's Ss had been frced t partitin the patterns int mutually exclusive subsets, but Handel and Garner btained a matrix f stimuli and assciates which suggested that Ss cnceive the patterns t be gruped int aseries f nested subsets. The implicit alternatives t a stimulus, thse figures that belng t its subset, thus may als belng t ne f the smaller grups nested within the subset, it

3 6 BEAR appears, but the figures lcated utside the subset in any rger grup which includes the subset d nt cnstitute alternatives t the stimulus. Handel and Garner develped tw measures f the number f implicit alternatives fr a pattern: the psitin f the pattern's subset in the nesting hierarchy (a lw-numbered psitin indicates a small inner subset) and the number f times the pattern was used as an assciate t ther patterns (a greater frequency f use indicates a small inner subset). The crretin between the tw measures was -.6, and they were clsely linearly reted t Garner and Clement's m easure, crreting.90 and -.7 with it. [These cefficients and the thers reprted belw are values fr Pearsn's r cmputed by Bear (970)]. The strng crretins between the measures frm the tw studies indicate that the inclusin r missin f the nine-cell matrix makes little difference t the Ss, it might be nted. Difficulty fencding Difficulty in encding the dt patterns has been measured in fur different ways. Clement asked Ss t. generate a ne-wrd name fr 0 f the patterns in ne study () and t learn t assciate a tw-digit number with 7 f the patterns in anther study (7). As indices f a pattern's encdability, he cmputed the median tency and the uncertainty (r variability) f the distributin f names which the Ss supplied fr the pattern in the naming task and the mean trials t criterin as a stimulus term and as a respnse term in the paired-assciates task. Crretins amng the measures ranged frm.7 t.9, with a median value f.6. Thus the patterns fr which Ss were slw in generating a name tended t be thse fr which they generally disagreed n the name and thse which required many trials t learn as a stimulus term and as a respnse term. Crretin Between Number f Alternatives and Difficulty fencding patterns. A variety f ther patterns studied by Handel and Buffardi () mayais prvide evidence fr the crretin. Ryer and Garner generated sequences f tnes by repeating a basic pattern f eight elements, each element ne f tw sunds; Handel and Buffardi used eight f these auditry sequences plus "transtins" f them int eight ther mdes f presentatin. In a visual versin, the elements f the patterns were tw lights dispyed sequentially rather than tw tnes, and in a tactile versin the elements were vibratins applied t the left r the right hand. In three ther versins, a basic eight-element pattern was presented first in ne mdality (auditry, visual, r tactile) and then in a secnd, and the alternatins were cntinued every eight elements; the three versins here were the three pssible pairs f mdalities. In anther three versins, the elements were a stimulus frm ne mdality (a tne, light, r vibratin) and a stimulus frm anther mdality, and again the three versins were all three pssible pairs. Handel and Buffardi determined the median number f elements in a sequence that the Ss bserved befre identifying a pattern, and this scre prvides a difficulty-f-encding measure. The rank rder f the eight sequences n this measure was little affected by the mde f presentatin, by the rate f presentatin, and by the pint in the basic pattern at which the sequence began, and Handel and Buffardi reprted nly an verall rank rder fr difficulty f encding. This rder crretes highly with the ranking f the patterns f the number-f-alternatives measure which Ryer and Garner btained fr the stimuli in their auditry versin (rh =.79; data frm Ryer and Garner's Table and Handel and Buffardi's Table ). In sum, data n a variety f stimuli indieate that a pattern with retively many implicit alternatives is a pattern which is retively diffieult t encde. This crretin prvides a datum which must be expined by any thery f the encding prcess. COMPETITORS AS IMPLICIT ALTERNATIVES The patterns which were difficult t encde in Clement's studies prve t be thse with many implicit alternatives. The fur measures f encding difficulty and the three measures f number f implicit alternatives yield a matrix f crretins, all in the "right" directin and ranging in abslute value frm.6 t.9, with a median f.0. Other Stimuli Mre evidence fr a strng crretin between number f implicit alternatives and difficulty f encding is avaible in data n ther stimuli. Gnzer, Taub, and Murphy () have reprted the crretin fr dt patterns f a different kind (their data were nt cmpletely cnsistent, hwever), and Ryer and Garner (6) have reprted the crretin fr auditry The crretin between number f implicit alternatives and difficulty f encding als suggests that the identificatin f specific alternatives t specific stimuli may prvide eiues t the encding prcess. Fr the dt patterns in this regard, Clement, fllwing an argument advanced in the Carner-Clement () paper, has asserted that the rtatins and reflectins f a pattern (the members f its equivalence set) are inferred as alternatives t it (Clement, Guenther, & Sistrunk, 97; Clement & Sistrunk, 97; Clement, Sistrunk, & Guenther, 970; Clement & Weiman, 970). There is evidence in the data n number f alternatives that in fact they are. In Garner and Clement's study, which tk the patterns judged simir t a stimulus t be representative f its implicit alternatives, the rtatins and reflectins f a stimulus were generally judged simir t it. In Handel and Garner's study, which tk

4 IMPLICIT ALTERNATIVES TO A STIMULUS 6 the patterns suggested bya stimulus t be representative f its implicit alternatives, the rtatins and reflectins f a stimulus were generally suggested t the Ss by the stimulus and were used as assciates in 9.% f the cases-abut 0 times as ften as wuld be expected if each pattern had the same chance fbeing assciated t each ther pattern. Clement implies, hwever, that rtatins and reflectins are the nly implicit alternatives fr the dt patterns, and there is evidence t the cntrary in Handel and Garner's data.' Their matrix f stimuli and assciates indicates that the implicit alternatives fr many f the patterns include ne r mre cmpetitrs f the pattern-ne r mre patterns which differ frm the stimulus nly in the psitin f a single dt and in a sense cmpete with the stimulus fr that dt (fr example, as an alternative t i and a as an alternative t d). In a majrity f the cases, it appears, the cmpetitr lcates the nncmmn dt in a psitin where it is mre predictable frm the ther fur. Stimuli and Assciatins Each f Handel and Garner's Ss respnded t each f the 6 patterns, and the researchers thus btained a matrix f 6 stimuli by 6 pssible respnses in which each cell entry indicated the number f Ss wh made the given respnse t the given stimulus. Because the fur r eight members f an equivalence set generay behaved the same way and ften elicited ne anther as assciates, as nted abve, the researchers averaged the frequency-f-assciatin scres ver the patterns within each equivalence set fr bth stimuli and respnses. This device reduced the data t a by matrix listing the mean frequency with which each f the fundamentally different stimuli elicited each f the fundamentally different respnses. "Duplicate" assciatins invlving rtatins and reflectins f the stimulus r f the respnse were averaged tgether in this matrix. Of the fundamentally different cases in which a stimulus elicited a respnse frm the same equivalence set (the cases n the diagnal in the matrix), all ccurred with a mean frequency greater than unity, the value fr a unifrm distributin in which each pattern was used as an assciate equally ften t each ther pattern. Of the 06 fundamentally different cases in which a stimulus elicited a respnse frm a different equivalence set (thse ff the diagnal), 7 ccurred with a mean frequency greater than unity. Of these 7 stimulus-respnse pairs, 6, r almst exactly half, are interpretable as assciatins which mved ne dt in the stimulus. Because Handel and Garner reprted data nly fr the reduced matrix, ne cannt rule ut the pssibility that sme f these assciatins als included a rtatin r reflectin f the stimulus, but it seems unlikely that many f them did. Seven f the 6 cases invlve Pattern and I b, which are nt altered by rtatin r reflectin, and there is n ambiguity abut the ne-dt change in these cases. Table I lists these 6 cases alng with the lwer bund f the average frequency with which each ccurred. Thus the number "" fr the first line f the table indicates that the eight patterns in Equivalence Set j elicited as an assciatin ne f the fur patterns f Set a with a mean frequency between nd ver the by cells invlved. The number "" in the third line, simirly, indicates a mean frequency between and fr the by assciatins, in which a pattern frm Set j was the stimulus and a pattern frm Set g was the respnse. The 6 cases in Table represent between 6.7% and.% f the,79 assciatins which Handel and Garner btained. (The uncertainty abut the percentage here and belw is the result f their reprting nly the lwer bunds fr the average frequencies.) Predictabilities f the Dts The ther data in Table I cncern the predictabilities f the figural elements. They were btained by the present authr (Bear, 97) frm Ss wh were shwn a pssible fur-dt subpatterns and asked t add t each a fifth dt "implied r suggested by thse already present." The percentage f Ss wh pced their dt in a given psitin in respnse t a given cnfiguratin f fur dts was taken as an index f the predictability f that dt in the ttal five-dt pattern. The predictability scres thus btained are reprted in Fig. I within the dts f the patterns. The scres there have been averaged ver tw factrs which accunted fr nly a small prprtin f the variance in the scres: patterns within equivalence sets and, in the case f sets f Size, structurally equivalent lcatins (lcatins switched by rtatins and reflectins which leave the remainder f the pattern unchanged, such as the tw crner dts in the figures f Sets a and c). As Table indicates, many f the assciatins interpretable as ne-dt changes are cases in which the respnse lcated the dt in a mre predictable psitin, thus creating what might be called astrnger cmpetitr f the stimulus-a pattern that is superir in cmpeting with the stimulus fr the nncmmn dt. The change was t a mre predictable psitin in f the 6 cases (thse with a psitive number in the final clumn f Table ). These accunt fr 7.% t 79.7% f the ne-dt changes and.% t.% f all assciatins. All 0 f the equivalence sets f Size have at least tw strnger cmpetitrs, and 6 f the sets f Size have at least ne. The increase in the predictability f the nncmmn dt between the stimulus and the respnse is retively trivial, less than 0 percentage pints in 7 f the cases but 0 pints r mre in 7 f the cases, which is ver half f them. In all but ne f these cases (the exceptin is i t Sd), it shuld be nted, the respnse pattern has nt just a higher predictability fr the nncmmn dt but a higher mean predictability fr its five elements, and

5 6 BEAR Table Assciatins Obtained by Handel and Garner' (6) are Interpeetable as One-Dt Changes Predictability f Diffe- Nncmmn Dt rence in Stim- Fee- in in Prediculus Respnse quency* Stimulus Respnse tability j i h g f e d c a k j i h g f e a h g a a f d h d d b h e j g b e d a d g a a b a a d f a h b e h b c g a b d c a d 0 9. r It r t 6 r t r r r r r that d c b a a f g j e f g i Table (Cntinued) Nte-Patterns are beled as in the Handel and Garner study and as in Fig.. "Lwer bund f avetage frequency with which the stimulusrespnse pair ccurred. Average was taken ver all members f the equivalence set f stimuli and ver all members f the equivalence set f respnses. Value wuld be unity if each pattern were used equally ften as an assciatin t each ther pattern. TMving either f tw dts in the stimulus pattern cnverts it t a respnse pattern in the indicated equivalence set. mean predictability f elements (which is indicated in Fig. n the bttm line belw each pattern) is clsely reted t number f implicit alternatives and t difficulty f encding. The crretins are -.9, -.7, and. with the number-f-alternatives measures and -.79, -., -.7, and -.7 with the difficulty-fencding measures; all values are in the "right" directin. Thus the trend tward a strnger cmpetitr in which the nncmmn dt is mre predictable frm the remaining elements is als a trend tward a pattern whse ther elements are mre predictable ne frm the thers and a trend tward a pattern which has fewer implicit alternatives and is mre easily encded. This trend accrds with the Gestaltists' w f Prägnanz, which asserts a tendency fr psychlgical prcesses t mve tward cnfiguratins f elements which are figurally "gd," i.e., simple, r easy t encde, and weil rganized, r cmpsed f predictable elements. Ss' judgments f "pattern gdness" fr the dt figures, in fact, crrete highly in the required directins with each f the ther measures described abve. Judgments cllected by Garner and Clement, by Handel and Garner, and by Clement () are clsely reted t each ther (r =.9-.99) and yield a set f cefficients far the ther measures that range in abslute value frm.6 t.9, with a median f.9. There are sme exceptins, f curse, t the trend tward astrnger crnpetitr with an increase in the predictability f the nncmmn dt. As Table shws, an increase failed t ccur in f the 6 cases f a ne-dt change, and in f these cases there was a decline f 0 percentage pints r mre. Same f the exceptinal cases, thugh, may be artifacts f Handel and Garner's prcedure. Their Ss may have made sme "unnatural" respnses because they were nt permitted t use a pattern as its wn assciatin r because they were bred with the task. 97

6 IMPLICIT ALTERNATIVES TO A STIMULUS 6 SCHEMA-PLUS-CORRECTION ENCODING The data frm which Table was derived were nt specifically cllected t prvide infrmatin n the encding f the dt patterns, and the nly firm cncusin which Table warrants isjust what it shws: The subset f alternatives which a S (n Garner's hypthesis) infers when presented with a dt pattern incudes nt just the rtatins and reflectins f the pattern but in many cases ne r mre ther patterns which differ frm the stimulus in the psitin f a single dt and that generally lcate that dt in a psitin where it is mre predictable frm the ther fur. Table des suggest, thugh, that certain f the patterns are encded as a "schema plus crrectin," at least at sme stage f the prcessing f the pattern in at least sme tasks, and abrief discussin f this matter may have sme heuristic value. The pssibility f schema-plus-crrectin encding was suggested sme years ag (Wdwrth, 9, Chapter ), but it seems t have been generally ignred in recent treatments f encding. The theries f the prcessing f sequential elements reviewed by Simn (97), fr example [Payne's (6) is anther such thery], and Vitz and Tdd's (97) mdel fr the perceptin f gemetric figures d nt permit this means f representing a pattern. The ne-dt changes which may cnstitute perhaps a fifth f Handel and Garner's assciatins, thugh, are pusibly interpreted as cases in which the S drpped the crrectin t a stimulus pattern encded as a schema plus crrectin, thereby revealing the schema in the pattern which he drew as a respnse. On this interpretatin, the patterns which ccur as respnses in Table represent nt just implicit alternatives t the stimuli listed in the table but als schemas which the Ss used in encding the stimuli. The equivalence sets t which the respnses belng are a, b, a thrugh j, and a,, and d. Mst f the schemas thus seem t be simple, well rganized "gd" figures, "natural prttypes" perhaps (Rsch, 97), easily encded themselves when they appear as stimuli and cmpsed f dts which are mre r less predictable ne frm the thers, as shwn in Fig.. The dt whse psitin differs between the stimulus and the schema, In particur, is generally lcated in a mre predictable psitin in the schema, and the schema is thus generally mre "pusible" than the stimulus, given the fur dts they have in cmmn (cf. Bruner, 97). The cncept f schema-plus-crrectin encding raises a number f questins which may be wrth pursuing, Fr example, hw is the schema selected? The generally greater predictability f the nncmmn dt in Handel and Garner's ne-dt-different assciatins suggests the pssibility that the selectin is made by extrapting the schema frm a sampie f the stimulus, and if this is s, the prblem then arises f hw the sampie is selected. A reted questin is hw different frm the stimulus the schema can be. Assciatins such as a t a and e t i suggest that nt nly ne-element but als tw-element differences are pssible fr the dt patterns. A third questin is why a stimulus such as h, which is apparently susceptible t several different schema-plus-crrectin encdings, shuld be mre difficult t encde than astimulus susceptible nly t ne r t nne at all, in keeping with the crretin between number f implicit alternatives and difficulty f encding. The mst basic questin, f curse, is whether the implicit alternatives pyacausal rle in the encding prcess r whether they are just a by-prduct, as Lappin has argued (97; Lappin, Snyder, & Bckburn, 97). REFERENCES Bear, G. Redundancy, predictability f figural elements, and figural gdness. (Dctral dissertatin, Yale University) Ann Arbr, Mich: University Micrfilms, 970. N. 70-, 6. Bear, G. Figural gdness and the predictability f figural elements. Perceptin & Psychphysics, 97,,-0. Bruner, J. S. On perceptual readiness. Psychlgical Review, 97,6,-. Clement, D. E. Uncertainty and tency f verbal naming respnses as crretes f pattern gdness. Jurnal f Verbal Learning & Verbal Behavir,,,0-7. Clernent, D. E. Paired-assciate learning as a crrete f pattern gdness. Jurnal f Verbal Learning & Verbal Behavir, 7,6,-6. Clement, D. E., Guenther, Z. c.,& Sistrunk, F. Incertidumbre y percepcin de patrnes: Reseiia y perspectiva. Revista Latinamericana de Psiclgia, 97,,77-. Clement, D. E., & Sistrunk, F. Judgments f pattern gdness and pattern preference as functins f age and pattern uncertainty. Develpmental Psychlgy, 97,,9-9. Clement, D. E., Sistrunk, F., & Guenther, Z. C. Pattern perceptin amng Brazilians as a functin f pattern uncertainty and age. Jurnal f Crss-Cultural Psychlgy, 970,,0-. Clement, D. E., & Weiman, C. F. R. Instructins, strategies, and pattern uncertainty in a visual discriminatin task. Perceptin & Psychphysics, 970, 7, -6. Garner, W. R. Uncertainty and structure as psychlgical cncepts. New Yrk: Wiley,. Garner, W. R. T perceive is t knw. American Psychlgist, 6,,-9. Garner, W. R., & Clement, D. E. Gdness f pattern and pattern uncertainty. Jurnal f Verbal Learning & Verbal Behavir,,,6-. Gnzer, M., Taub, T., & Murphy, R. An evaluatin f three theries f figural rganizatin. American Jurnal f Psychlgy,,,-66. Handel, S., & Buffardi,. Pattern perceptin: Integrating infrmatin presented in tw mdalities. Science,,6, Handel, S., & Garner, W. R. The structure f visual pattern assciates and pattern gdness. Perceptin & Psychphysics, 6,,-. Lappin, J. S. Transfrmatin-invariant cues in the recgnitin f simple visual patterns. Perceptin & Psychphysics, 97, 0, Lappin, J. S., Snyder, C. R., & Bckburn, C. The encding f perceptual infrmatin in the rganizatin f individual stimulus patterns. Perceptin & Psychphysics, 97, 0, -.

7 66 BEAR Payne, B. The retinship between a measure f rganizatin fr visual patterns and their judged cmplexity. Jurnal f Verbal Learning & Verbal Behavir, 6,, -. Prkhvnik, S. J. Pattern variants n a square field. Psychmetrika, 99,,9-. Rsch, E. H. Natural categries. Cgnitive Psychlgy, 97,, -0. Ryer, F.., & Garner, W. R. Respnse uncertainty and perceptual difficulty f auditry tempral patterns. Perceptin & Psychphysics, 6, I, -7. Simn, H. A. Cmplexity and the representatin f patterned sequences f symbls. Psychlgical Review, 97, 79, 69-. Vitz, P. C., & Tdd, T. C. A mdel f the perceptin f simple gemetrie figures. Psychlgical Review, 97,7,07-. Wdwrth, R. S. Experimental psychlgy. New Yrk: Hlt, 9. NOTES. Garner has referred t the stimuli in the subset which he hypthesizes the S t infer as "equivalents" t the stimulus as well as "alternatives" t it. The wrd "alternatives" is used here t avid cnfusin f the hypthetical subjective subset with the bjectively defined equivalence set f rtatins and reflectins. Anther term emplyed in reference t the inferred stimuli is the "uncertainty" f the presented stimulus.. Garner and Clement reprted nthing abut which particur patterns were judged simir t which ther s, except that "mst f the Ss kept the reflectin and rtatin equivalence grups intact [p. ]." Their study thus des nt speak t the present issue.. The judgments f pattern gdness were btained t test Garner's () hypthesis that a gd figure has retively few implicit alternatives. As the present review indicates, the hyp thesis has been strngly cnfirmed. (Received fr publicatin Octber, 97; accepted Octber,97.)