European Journal of Psychology of Education1991, Vol. VI, n? 3, 291-301© 1991, I.S.P.A.

Progress to Conservation:Conflict or Correct Answer?

Jan BijstraSandy JacksonPaul van GeertState University of Groningen, Groningen, The Netherlands

One of the fundamental problems in socio-cognitive conflict theoryconcerns what it is that leads to cognitive growth. Is it conflict perse, i.e. the fact that two contradictory opinions are brought together,or is it the presence of the correct answer which is essential for growth.In this experiment, dyads, functioning on the same cognitive level, wereformed and asked to solve a conservation-of-lengtn task. Theclassification of the children in the pre-test was not done accordingto Piagetian norms, but according to Flavell's appearance-reality (AR)model: AR non-conservers (AR-NC), AR intermediates (AR-I) and ARconservers (AR-C). Many children who would have been scored as non­conservers in a standard Piagetian task, showed an underlyingconservation competence and were classified as AR-I. The results ofthe interactionsuggest that conflict does not lead to appropriatechangein AR-NC dyads or AR-I dyads. Furthermore, the results suggest thatthe most effective method for AR-I to become conservers, is to makethem think about a problem and then, to createconsensusby confrontingthe children with others who have also reached the correct solution.

Introduction

Since the 19708, socio-cognitive conflict theorists (e.g. Doise & Mugny, 1975; Doise,Mugny, & Perret-Clermont, 1976; Perret-Clermont, 1980; Doise & Mugny, 1984) havesystematically studied the relationship between cognitive development and children's socialinteractional experiences. According to these authors, confrontation with others can be avery powerful stimulant to the restructuring of cognitions. While Piaget considered cognitivedevelopment as an intra-individual process, socio-cognitive theorists stressed the importanceof inter-individual processes for further development.

Theorists have provided different explanations for the relationship betweenan interactionalexperience and cognitive restructuring. Daise and his colleagues have argued that the conflictitself is important, i.e. the fact that two contradictory opinions are brought together. Thishypothesis. implies that progress need not be restricted to interactions between children at

292 J. BIJSTRA, S. JACKSON & P. VAN GEERT

different cognitive levels (cognitive unequals), it may also occur between children who areat the same level (cognitive equals). Russell (l982a, 1982b, 1984) takes a different position.He emphasises that the presence of the correct answer is essential for cognitive growth, i.e,that children need to hear the correct answer from another. According to Russell (l982a),children will never attempt to coordinate their perspectives, any more than adults ever reallytry to reach agreement that a film was enjoyable. A corollary of Russell's hypothesis is thatchildren at the same cognitive level will not benefit from interactions, unless the correctanswer is put forward.

Much of the research on socio-cognitive conflict has focussed attention on the effectof interaction on children's conservation-knowledge. Most experiments with dyads and triadsof conservers and non-conservers (i.e. cognitive unequals) have shown a significant amountof cognitive progress for the less advanced children (e.g. Murray, 1972; Silverman & Stone,1972; Silverman & Geiringer, 1973; Perret-Clermont, 1980; Russell, 1982a; Doise & Mugny,1984). These results, however, do not shed any light on the conflict/correct answer discussion,because they can be readily explained by one or other of the two hypotheses. One mightanticipate that experiments with cognitiveequals should be able to resolve the debate: 'progress'argues for the conflict hypothesis and 'no progress' for the correct answer hypothesis.Unfortunately, experimental results were rather inconsistent. Doise, Mugny and Perret-Clermont(1976), Doise, Rijsman, Van Meel, Bressers and Pinxten (1981, experiment 1) and Ames andMurray (1982) found that children were able to benefit from interactions with cognitive equals,but Rijsman, Zoetebier, Ginther and Doise (1980), Doise,Rijsman, Van Meel, Bressers andPinxten (1981, experiment 2) and Russell (1982a, 1982b) failed to find any progress on thepart of their subjects (see also Taal, 1984, for a review). Of course, this inconsistency canpartly be explained by the fact that cognitive equal opinions do not necessarily need to becontradictory opinions: children can simply agree that pencil A is longer than pencil B. Inthose cases, there is no reason to expect progress.

The above studies concerning interaction-effects on conservation-knowledge, are allcharacterised by the fact that cognitive progress is viewed within the classical Piagetianclassification. Thus, in pre- and post-test situations, children are classified as non-conservers,intermediates or conservers according to Piaget's criteria (Piaget & Szeminska, 1952). Inthe last two decades, however, several investigators (e.g. Rose & Blank, 1974; McGarrigle& Donaldson, 1974; Schiff, 1983; Moore & Frye, 1986) have criticised Piaget's conservationconcept and advanced new interpretations, These experimenters have all focussed on theperformance-competence question and, in particular, on the idea that the classical Piagetianconservation approach may, for one reason or another, under-estimate the cognitive levelof a substantial group of children, Starting from this idea, Bijstra, Van Geert and Jackson(1989) gave 5-, 6- and 7-year-old children a newly constructed conservation-task in whichthe conservation-questions were alternately 'standard' or posed in terms of appearance andreality, i.e. the question 'how is it really' was preceded by 'how does it look' (see also Russell,1982a, 1982b; Russell & Mitchell, 1985). They found that significantly more children gavecorrect conserving answers to the 'how is it (reallyj-question when it was preceded by the'Iooks-question, than when the latter question was missing (i.e, the 'standard' situation).

On the basis of these results, Flavell's appearance-reality (AR) model (Flavell, Flavell,& Green, 1983; Thylor & Flavell, 1984; Flavell, Green, & Flavell, 1986) was proposed as abetter alternative for describing the development of children's conservation knowledge thanthe classical Piagetian model. While first-level children (in terms of Bijstra et al: appearance­reality non-conservers or AR-NC) make phenomenism errors, i.e, emphasise the appearanceaspect of the situation, regardless of whether the question refers to the appearance- or thereality-aspect, second-level children (AR-intermediates or AR-I) generally give conservinganswers to the reality-questionbecause, what is expectedof them is made clear by the differencebetween the two questions. In the Piagetian standard procedure, however, both AR-NC (first­level children) and AR-I (second-level children) answer in terms of how things are, but theevidence clearly suggests that AR-NC really think that they are as they look, while AR-I

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actually know better. Thus, although there is a difference between AR-NC and AR-I, thestandard procedure does not often differentiate between the two.

Bijstra et al's findings could have important implications for the conflict vs correctanswer discussion. The fact that the standard procedure does not often differentiate betweenAR-NC and AR-I could mean that experimentersassumed that they were working with equal­level dyads, when they were, in fact, using mixed dyads, i.e, AR-NC with AR-1. As pointedout above, mixed dyads of this composition are not really equal-level. Where dyads weremixed in this way, progress could be ascribed either to conflict within the dyad or to thepresence of the correct answer (of course, it was also possible that experimenters were workingwith AR-I1AR-I dyads; in that case, the dyads were equal-level but the correct answer wasimplicitly present by both children). Thus, the above experiments with cognitive equals stilllead to no resolution of the conflict vs correct answer discussion, because the standardprocedure is not always capable of controlling how the dyads are composed: AR-NC/AR­NC, AR-I1AR.-I or AR-NC/AR-I.

The present experimentaims to clarify the conflictvs correct answerdiscussionby buildingupon the findings of Bijstra et al. (1989). Instead of using the Piagetian classification, thethree levelAR-classification is used as the criterion for determining children's cognitive levelin the pre-test" By pairing AR-NC with AR-NC and AR-I with AR-I in the interaction phase,dyads are formed which are really equal-level. If neither AR-NC nor AR-I benefit from theinteraction, this will lend support to the correct answer hypothesis: as long as the correctanswer is not explicitly present in the sense that one child hears it from the other, they donot benefit from the interaction. If both AR-NC and AR-I show progress after interaction,the conflict hypothesis is confirmed: exposure to the correct answer is no necessary pre­requisite for children to spontaneously produce it after interaction. If only the AR-I benefitfrom the interaction, again conflict has had an effect. This effect, however, should not beunderstood in terms of establishing cognitive restructuring - as is the case when AR-NCalso benefit from the interaction - but rather, in terms of bringing to the fore the underlying,correct answer, If this modified conflict hypothesis is true, the contradictory results withdyads of the same cognitive level can be clarified by the suggestion that the 'progress­experiments probably worked with non-conservers who were actually AR-I, while the 'no­progress-experiments probably used children who would have been classified as AR-Ne.

Method

Subjects

A total sample of 164 children was confronted with the standard conservation-of-lengthtask. Following the AR conservation-of-length task, 124 of these children were identifiedas either AR·NC or AR-1. These children were assigned to the following conditions:

1. AR-NC/interaction: n = 22, range 5:1 - 7:9, mean age 6:2.2. AR-I1interaction: n = 24, range 5:0 - 7:9, mean age 6:7.3. AR-NC/no-interactionl2 (i.e, 2 measurements, see procedure): n 20, range 5:3

- 7:4, mean age 6:3.4. AR-I/no-interactionl2: n = 22, range 5:0 - 7:9, mean age 6:7.5. AR-NC/no-interaction/3 (3 measurements, see procedure): n = 13, range 5:0 ­

7:10, mean age 6:2.6. AR-I1no-interaction/3: n = 23, range 5:0 - 7:10, mean age 6:4.

Material ana' procedure

L Pre-test. All 164children were given a standard conservation-of-Iength task (using two

294 J. BIJSTRA, S. JACKSON & P. VAN GEERT

unsharpened pencils of equal length). If the children gave a conserving answer and a correctjustification to the post-transformation question and did not change this after a counter­suggestion, they were classified as conservers and excluded from the experiment (n = 38).Children were classified as standard non-conservers (stand-NC) if they answered both questions(i.e. before and after the counter-suggestion) incorrectly and as standard-intermediates (stand­I) if they changed their answer from correct to incorrect or vice versa. The latter two groupsof children were then exposed to the so-called AR conservation task. This task consistedof six pairs of two statements with which the children could agree or disagree. The first,third and fifth pair consisted of 'standardtstatements, i.e, conser vation-statements withoutreference to the AR-distinction. Pairs 2, 4 and 6 consisted of an appearance-statement incombination with a reality-statement (AR-statements), so that the effect of the appearance­statement on the reality-statement could be studied (see Table 1).

Thble 1Statement-pairs used in the AR task (if children judged pencil A longer in pair 1, theexperimenter took A as longer for the other statements as well)

Pair 1

Pair 2

Pair 3

Pair 4

Pair 5

Pair 6

a. Pencil A is longer.b. Pencil B is longer.

a. Pencil ..... is really longer.b. It looks as if pencil ..... is longer.

a. Both pencils are the same length.b. Pencil ..... is longer.

a. It looks as if pencil ..... is longer.b. Pencil ..... is really longer.

a. Pencil A is longer.b. Pencil B is longer.

a. Pencil ..... is really longer.b. It looks as if pencil ..... is longer.

The experimenter read out both statements in the first pair twice and then read outstatement la again. Children were then asked to judge if it was correct or incorrect. Theexperimenter then read out statement lb and it was judged by the children. This procedureoffered children the opportunity to compare the different meanings of two statements withina pair, but still judge them independently. The other pairs of statements were systematicallydealt with, in the same way. Children were first offered pairs of practice-statements so asto ensure that they understood the judgment task. No child was excluded because of failureto understand the procedure. Children were classified as AR-NC if no more than oneconservation-statement was answered correctly, as AR-I if answers to two, three, four orfive conservation-statements were correct and as AR-C if all conservation-statements wereanswered correctly. As with those 38 children initially identified as standard conservers, AR­C (n = 2) were also excluded from the experiment which leaves 124 children for the interactionphase.

/I. Interaction phase. The interaction phase took place about one week after the pre­test. For the two interaction conditions, AR-NC/AR.-NC dyads and AR-IIAR-I dyads wereformed. As far as possible, dyads were of the same sex and from the same class. Beforethe interaction started, one child was asked the standard conservation question (the so-called'pre-interaction-test'), while the other child waited outside the testing-room. The second child

PROGRESS 10 CONSERVATION 295

was then admitted, invited to sit opposite the first child and then he/she was also askedthe standard question. In order to create conflict, the experimental situation was such thatpencil A pointed in the direction of one child while pencil B pointed in the opposite directiontowards the other child (see Russell, 1982a). If the two children had contradictory opinions,their attention was called to this and they were asked to come to one common answer, the'post-interaction-decision'. The experimenter's task was to stimulate discussion and toemphasise that only one answer was required.

The control conditions AR-NC/no-interactionl2 and AR-I/no-interactionl2 were onlypre- and post-tested (the '2' refers to two measurements: pre- and post-test). The controlconditions AR-NC/no-interaction/3 and AR-I/no-interaction/3 were introduced to controlfor a repeated measurement effect. As in the introductory part of the interaction conditions,these children were again confronted with the conservation-of-length task, one week afterthe pre-test. Instead of creating an interaction situation, however, the session was endedimmediately after the children had answered the question ('3' refers to three measurements:pre-test, a measure one week after pre-test and post- test). For clarity's sake, the secondmeasure was also called 'pre-interaction-test', although the term is not correct, of course,since the children did not in,teract.

IlL Post-test. About a week after the interaction phase, the 124children who had takenpart in the interaction phase, wereconfronted with the AR conservation task, described aboveand the Piagetian standard task. The results were examined in the light of both post-tests.Note that the appearance-reality problem was only mentioned to the children in the AR­pre-test and in the AR- post-test but not in the interaction phase (see figure 1 for the completedesign).

x X+lweek

Interaction

x + 2 weeks

Interaction Pre-test Pre-interaction-test Post-interaction-decision Post-test

No-Interactionl2 Pre-test Post-test

No-Interaction/3 Pre-test Pre-inter-action-test Post-test

Figure 1. Experimental design

Results

Pre-test

The standard conservation task led to 92 children being classified as standard non­conservers (stand-NC), 34 as standard intermediates (stand-I) and 38 as standard conservers

296 J. BIJSTRA, S. JACKSON & P. VAN GEERT

(as noted, the conservers were excluded from further experimentation). Following the ARtask, the stand-NC and stand-I were divided as follows: 55 AR-NC, 69 AR-I and 2 AR-C(the AR-C were also excluded from the experiment).

Comparison of the total AR-NC score with the total AR-I score

Table 2 shows the post-test results of the three conditions for the AR-I and the AR-NC.Both AR post-test results and standard post-test results are presented. When the total AR­NC score (i.e, the AR-NC/interaction condition and both AR-NC/no-interaction conditionstaken together) was compared with the total AR-I score (i.e, the AR-I1interaction conditionand both AR-I/no-interaction conditions taken together), it appeared that there was a clearsignificant difference between these two scores on both post-test measures: AR post-test,X2(l , n= 119) :: 68.90, p < .001; standard post-test, X2

(1, n= 120) = 22.15, P < .001. Thisresult strongly supports Bijstra et ai's (1989) conclusions that AR-NC and AR-I are twoclearly distinguishable groups.

Table 2AR post-test results and standard post-test results of the three conditions for the AR-NCand AR-I

AR post-test Standard post-test

Condition AR-NC AR-I AR-C NC C

AR-NC/interaction 16 5 0 17 2 2AR-NC/no-interactionl2 15 5 0 13 5 2AR-NC/no-interactionl3 11 I I 10 0 3Total AR-NC score 42 11 1 40 7 7

AR-I/interaction 1 8 13 2 5 15AR-I/no-interactionl2 0 16 4 8 6 7AR-I1no-interaction/3 4 13 6 11 4 8Total AR-I score 5 37 23 21 15 30

Comparison of the interaction conditions with the no-interaction conditions

The next step was to compare the interaction conditions with the no-interaction conditionsin order to study whether interaction effects could be found. With regard to the AR-NC,the interacting children did not show better performance than the children in both AR­Ne/no-interaction conditions. Comparison of the interaction condition with the AR-NC/no­interactionl2 condition yielded the following results: AR post-test, X2(1, n= 41) :: 0, NS;standard post-test, X2(l , n= 41) :: 1.80, NS. When the interaction condition was comparedwith the AR-NC/no-interaction/3 condition, the following results were found: AR post-test,X2(l , n= 34) :: 2.87, NS; standard post-test, X2(1, n= 34) :: 2.26, NS.

The interacting AR-I, on the other hand, showed significantly better performance thanthe children in both AR-I1no-interaction conditions. Comparison of the interaction conditionwith the AR-I/no-interactionl2 revealed the following results: AR post-test, X\t, n= 43)::8.36, p < .015; standard post-test, X2(1, n= 43) :: 6.58, p < .037. As table 2 clearly shows,there were considerably more conservers in the interaction condition than in the AR-IIno­interactionl2 condition on both post-test measures. Furthermore, there also was a significantdifference between the AR-I in the interaction condition and those in the AR-I/no-interactionl3

PROGRESS 10 CONSERVATION 297

condition on the standard post-test: X2(1, n= 45) = 8.45, P < .014. On the AR post-test,however, significance did not reach the .05 level, although it came close to it: X2(1, n= 45)= 5.55, p < .062. Table 2 shows again that there were many more conservers in the interactioncondition than in the AR-I/no-interaction/3 condition on both post-test measures.

The interactions

The interaction situations were further examined in detail in order to see if they couldshed more light on the post-test results. Table 3 shows the pre-interaction-test results (children'sanswers to the standard conservation question which was posed immediately before theinteraction), children's post-interaction decisions and the AR and standard post-test results.Note that only two AR-NC/AR-NC dyads had no conflict since they immediately agreedabout the NC-answer which they had individually given. Apparently, for most dyads theexperimental situation was strong enough to induce conflict.

Inspection of Table 3 reveals that many AR-I, despite their classification in the pre-testas AR-I, started the interaction as conservers: 6 dyads of children had become conserversin the pre-interaction-test while in 5 other pairs, one of the two children had become aconserver. In other words, most post-test conservers were already conservers before theinteraction situations had even begun. Apparently, the AR task in itself was so effectivethat it led AR-I to become conservers. The results in the AR-I/no-interaction/3 conditionconfirm this suggestion: half of the children in this condition gave conserving answers inthe pre-interaction-test. Because the children were randomly assigned to the different

Table 3Children's pre-interaction-test results and their post-interactions decisions

Post-test resultsPre-interaction-test

Post-interaction decisions AR Standard

NC I C NC C

7 pairs of 2 NC-answers2 could not reach agreement 3 1 0 3 1 02 judged both NC-answers being correct 4 0 0 4 0 01 chose I NC-answer as the correct one 2 0 0 2 0 02 had 110 conflict; they agreed about the

same individually given NC-allswer 2 2 0 3 0

3 pairs of 1 C-answer/l NC-answer2 could not reach agreement 2 1 0 3 0 01 chose C-answer as the correct one 2 0 0 1 1 0

1 pair of 2 C-answersjudged two NC-answers being correct 0 0

6 pairs of :;: C-answersagreed about C-answers 0 3 8 0 2 9

5 pairs of I C-answer/l NC-answer3 chose C-answer as the correct one 0 4 0 1 41 chose NC-answer as the correct one 1 0 1 0 1I could not reach agreement 0 I 0 1 1

1 pair of 2 NC-answersjudged both NC-answers being correct 0 2 0 0

298 J. BIJSTRA, S. JACKSON & P. VAN GEERT

conditions, it can reasonably be assumed that many of the children in the AR-I1no­interactionl2 condition (thus, the children who were only pre- and post-tested) would alsohave given conserving answers, if they had been given the pre-interaction-test.

Thus, the fact that so many of the children had become conservers before the interactionmeans that the interaction-effect found in the post-test, cannot be attributed to a conflict'between two interacting partners at the same cognitive level. The consequence of the ARpre-test was that many children, viz. the six pairs who started the interaction with two correctanswers, did not have a conflict. Nevertheless, there were significant differences betweenthe AR-I1interaction condition and the two no-interaction conditions, so that the interactiondid have an effect. Table 3 shows that the six conserver/conserver dyads are, to a very greatextent, responsible for this effect.

The interactions within these dyads - although 'interaction' is a hardly appropriateexpression when two children immediately agree about a certain problem - apparently gavechildren the opportunity to affirm and consolidate their not so definitely established, butnevertheless correct answer. Children who did not have this opportunity (as was the casein the two no-interaction conditions) mostly remained Piagetian non-conservers orintermediates on the standard task and AR-I on the AR task. Thus, interactions did notfunction as correct information providing situations, but rather as consensus creating situations(see also Bijstra, 1989).

One of the most interesting findings about dyads which started with two non-conservinganswers, was that some of them tried to avoid conflict by concluding that both non-conservinganswers were in fact correct. This was the case with the non-conserver/non-conserver dyadin the AR-I1interaction condition and with two non-conserver/non-conserver dyads in theAR-NC/interaction condition. Furthermore, one dyad in the AR-NC/interaction conditionwho started the interaction with two conserving answers, changed these answers during theinteraction to two non-conserving answers and also came to the final conclusion that bothnon-conserving answers were correct. All of these dyads characteristically agreed that onepencil was longer for one partner, while the other pencil was longer for the other partner.Furthermore, the dyads held the opinion that if each partner simply changed seats withthe other, they would also change their judgment as to which pencil was longer. Apparently,for these children, one pencil is not longer than the other in an absolute sense. It dependson how you look at it: «This one's longer for me and that one's longer for you, but if wechange seats, that one will be longer for me and this one will be longer for you.»

Discussion

The main goal of the present experiment was to examine whether the contradictoryfindings from socio-cognitive conflict investigations with NC/NC dyads could be clarifiedwith the help of Flavell's appearance-reality model (Flavell, Green, & Flavell, 1986). Insteadof using the standard Piagetian classification based on Piaget and Szeminska (1952), childrenwere classified as AR-NC (first-level children) or AR-I (second-level children) on the basisof a conservation AR task developed by Bijstra, Van Geert and Jackson (1989). Three possiblehypotheses were suggested:

the correct answer hypothesis,the conflict hypothesis,the modified conflict hypothesis.

The correct answer hypothesis assumes that the explicit presence of the correct answeris a necessary pre-requisite for further development. The conflict hypothesis suggests thatconfrontation between two contradictory, but incorrect opinions may be sufficient for cognitivegrowth. The modified conflict hypothesis is based on the idea that while conflict per se

PROGRESS TO CONSERVATION 299

may be effective, it should not be understood as establishing cognitive restructuring, butas bringing the underlying, correct answer to the fore.

The results show that the AR-NC did not benefit from the interaction. The childrenwho were exposed to an interaction situation, did not perform any better than those in thetwo no-interaction conditions. The conflict hypothesis cannot therefore be confirmed.Furthermore, the fact that the interacting AR-I obtained better results than the non-interactingAR-I, also seems to disconfirm the correct answer hypothesis. If the explicit presence ofthe correct answer is a necessary pre-requisite for further development, neither AR-NC norAR-I should show progress. At first sight, the results seem to lend support to the modifiedconflict hypothesis which suggests that the effect of interaction should not be understoodin terms of establishingcognitive restructuring, but rather in terms of bringing the underlying,correct answer to the fore.

The results also reveal, however, that the interaction situation did not function as asituation in which two non-conserving opinions were changed to conserving answers. Theresults show clearly that the pre-test AR task and not the interaction situation, brought aboutmost children's correct answers. The AR task in itself led to so much progress that somedyads did not have a conflict (both members started the interaction with conserving answers)and other dyads were not at the same cognitive level (conserving answers were paired withnon-conserving answers). In other words, the fact that almost no AR-I/AR-I dyads startedthe interaction with two contradictory non-conserving opinions means that the modifiedconflict hypothesis cannot be completely confirmed or denied. However, the behaviour ofchildren during the interaction situations which did start with two non-conserving answers,does not point in the direction of the modified conflict hypothesis. A basic condition foreither of the conflict hypotheses to be true, ·is that children do indeed consider twocontradictory, incorrect opinions as conflicting. However, some dyads simply avoided conflictby concluding that both non-conserving opinions were correct: «this one's longer for meand that one's longer for you, so we are both right» (cf, Russell's observations, I982a, p.83). It seems evident that children are unlikely ever to learn from interactions of this sort.

Despite the fact that the AR task and not the interaction, brought about the correctanswer in the interaction condition, the results nevertheless showed some sort of interactioneffect. Apparently, the. interaction - in so far as 'interaction' is the correct word when twochildren immediately agree about a particular task - gave children the opportunity to affirmand consolidate each other 's underlying, correct answer. Where this possibility was absent,the results of the no-interaction conditions show that for most children, the pre-test hadceased to be effectivewhen they were post-tested. Thus, although the post-test results treatedin isolation seem to disconfirm the correct answer hypothesis, analysis of the post-test resultsin combination with the interactions show that the latter can be explained in terms of thenecessary presence of the correct answer.

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Key words: Conservation, Contradictory opinions, Correct answer, Socio-cognitive conflict.

Received: March 1990

Revision received: September 1990

Jan Bijstra. Psychologisch Instituut Heymans, Grote Kruisstraat 2-1, 9712 1"8 Groningen, The Netherlands.

Current theme of research'

Psycho social functioning of children after a Iivertransplantation, Adolescent's identity development and the effectsof social skills training.

Most relevant publications in the field of Educational Psychology:

Bijstra, J. 0., Van Geert, P, & Jackson, A. E. (1989). Conservation and the appearance-reality distinction: what dochildren really know and what do they answer. British Journal of Developmental Psychology. 7, 43-53.

Bijstra, J. 0. (1989). 1b be or to look, that's the question. A comparative study on cognitive and social-cognitivedevelopment. Unpublished dissertation: University of Groningen.

Sandy Jackson. Psychologisch Instituut Heymans, Grote Kruisstraat 2-1, 9712 TS Groningen, The Netherlands.

PROGRESS TO CONSERVATION

Current theme of research:

Social development - especially in adolescence, Social skills - especially in adolescence.

Most relevant publications in the field of Educational Psychology:

301

Jackson, A. E. (1987). Perceptions of a new acquaintance in adolescence. Unpublished dissertation: University ofGroningen,

Jackson, A. E. (191\9). Caide aux jeunes en difficulti: Ie role possible de l'ecole. L'Orientation Scolaireet Professionelle;4, 337-350.

Bosma, H. A., & Jackson, A. E. (1990). Coping and self concept in adolescence. Heidelberg: Springer Verlag

Paul van Geert. Psychologisch Instituut Heymans, Grote Kruisstraat 2-1, 9712 TS Groningen, The Netherlands.

Current theme of research:

Dynamic systems of cognitive development.