International audienceGeovisualization applications typically organize data into layers. These layers hold different types of geographical features, describe different characteristics of the same features, or represent those features at different points in time. Layers can be composited in various ways, most often employing a juxtaposition or superimposition strategy, to produce maps that users can explore interactively. From an HCI perspective, one of the main challenges is to design interactive compositions that optimize the legibility of the resulting map and that ease layer comparison. We characterize five representative techniques, and empirically evaluate them using a set of real-world maps in which we purposefully introduce six types of differences amenable to inter-layer visual comparison. We discuss the merits of these techniques in terms of visual interference, user attention and scanning strategy. Our results can help inform the design of map-based visualizations for supporting geo-analysis tasks in many application areas

This study develops a single elicitation method to test the acquisition of third-person pronominal objects in 5-year-olds for 16 languages. This methodology allows us to compare the acquisition of pronominals in languages that lack object clitics ("pronoun languages") with languages that employ clitics in the relevant context ("clitic languages"), thus establishing a robust cross-linguistic baseline in the domain of clitic and pronoun production for 5-year-olds. High rates of pronominal production are found in our results, indicating that children have the relevant pragmatic knowledge required to select a pronominal in the discourse setting involved in the experiment as well as the relevant morphosyntactic knowledge involved in the production of pronominals. It is legitimate to conclude from our data that a child who at age 5 is not able to produce any or few pronominals is a child at risk for language impairment. In this way, pronominal production can be taken as a developmental marker, provided that one takes into account certain crosslinguistic differences discussed in the article. ARTICLE HISTORY

No abstract

Previous studies have established a correlation beween early clitic omission and the existence of past participle agreement, explainable with a maturational constraint -the UCC. Since Portuguese doesn't show past participle agreement, it is expected that portuguese children will produce clitics early on. I order to find out whether this correlation holds for Portuguese, an experimental study was conducted reproducing Schaeffer's 1997 and adapting it to particular properties of Portuguese -the availability of null objects and variability of clitic position. The results of this study suggest that Portuguese children do omit clitics, apparently contradicting previous studies. Since clitic omission lasts until later than in other languages, we hypothesize that the explanation may rely on complexity factors.

Ce document est protégé par la loi sur le droit d'auteur. L'utilisation des services d'Érudit (y compris la reproduction) est assujettie à sa politique d'utilisation que vous pouvez consulter en ligne.https://apropos.erudit.org/fr/usagers/politique-dutilisation/ Cet article est diffusé et préservé par Érudit.Érudit est un consortium interuniversitaire sans but lucratif composé de

In this paper, we argue that clitic omission in European Portuguese speaking children cannot be due to a late acquisition of pragmatics. Based on experimental data from an elicited production task and a truth-value judgement task, we show that children acquiring European Portuguese as a first language know the appropriate pragmatic conditions for producing clitics and null objects and interpret clitics and null objects in the appropriate pragmatic context. However, their knowledge of some syntactic constraints on null objects, which are grammatical only in certain contexts in the adult grammar, is not fully mastered yet. The results obtained provide additional evidence in support of the idea that some aspects of pragmatics are acquired early and that some aspects of syntactic knowledge are acquired late.

This paper investigates how European Portuguese children interpret null and overt subject pronouns of adverbial clauses when there are two potential antecedents in the main clause, in order to find out how early the preferred readings are acquired in European Portuguese for each type of pronoun. Our results show that the control group of adults behaves as expected, choosing more often subject antecedents for null subjects and non-subject antecedents for subject pronouns, but children are predominantly at chance. The preferred interpretation for null subjects is acquired earlier than the one for overt pronouns and anaphoric contexts are acquired earlier than cataphoric ones. We attribute this developmental pattern to the fact that null pronouns are morphosyntactically more deficient and less dependent on semantic, discourse and prosodic factors, and to processing constraints related to the linear position of the antecedent.

Please cite this article in press as: Costa, J., et al. AbstractThis paper reports a study on the acquisition of clitic placement by European Portuguese children aged 5, 6 and 7, using an elicitation task. Contrarily to what has been found for other languages, where children correctly place clitic pronouns from a very early age, our results show that European Portuguese children still misplace clitics at age 7, although there is a developmental effect from 5 to 7: they overuse enclisis in proclisis contexts, but not the other way round. This confirms previous studies based on spontaneous production. Our study shows, however, that: i) the rates of clitic misplacement are not identical in all proclisis contexts; ii) proclisis is acquired earlier in some contexts; iii) the contexts that are harder to acquire are the ones where we find more variability in the adult control group, and where diachronic data are not so categorical. We argue that, since clitic placement in European Portuguese is not linked to the finite/non finite distinction, there is a slower developmental path, reflecting the complexity of the input and the specific properties of lexical items and syntactic contexts.