Generating collective spatial references

Generation of Referring Expressions is concerned with distinguishing descriptions for target referents in a knowledge base. Plural reference introduces novel problems, one of which is the collective/distributive distinction. This paper presents an empirical study of the production of collective spatial references, and an algorithm that determines content for such expressions from spatial data.peer-reviewe

Structuring knowledge for reference generation : a clustering algorithm

This paper discusses two problems that arise in the Generation of Referring Expressions: (a) numeric-valued attributes, such as size or location; (b) perspective-taking in reference. Both problems, it is argued, can be resolved if some structure is imposed on the available knowledge prior to content determination. We describe a clustering algorithm which is sufficiently general to be applied to these diverse problems, discuss its application, and evaluate its performance.peer-reviewe

ZeroCO2 buildings – how low can we go : a case study of a small hotel in Gozo

This study has shown that a new typical hotel building in Malta can reduce its CO2 emissions by more than 75 % over a chosen reference scenario with a relatively reasonable payback period of approximately 8 years. Such a reduction in CO2 emissions is possible by tackling the main energy consumer for hotels i.e. energy consumption for hot water. Various Energy efficiency and renewable energy combination of measures were considered in this study, however air to water heat pumps combined with roof and facade mounted photovoltaic's produced the lowest CO2 emissions. Policy to achieve near zero energy/CO2 emissions hotels should therefore focus on implementing renewable energy solutions for generating hot water and facilitating the transition of integrating renewable energy with the facade.peer-reviewe

Girls studying physics at post-secondary level in Malta

All secondary level students in Malta study, at least, one science subject (Physics, Chemistry and/or Biology) up to school-leaving level. This is due to a pass in one science subject being compulsory for entry into general post-secondary education. On the other hand, Physics, rather than Chemistry or Biology, is compulsory in State Schools. This ensures that a large percentage of girls, in Malta, study Physics. Analysis of Physics exam results at school-leaving level, the Secondary Education Certificate (SEC), shows that there is little difference, if any, in performance between boys and girls in the overall grade. A specific study has shown that the only consistent difference obtained was in coursework, this favouring girls with a moderate effect size of 0.35 and 0.57 for two consecutive years. When one considers the number of students opting to study Physics at Advanced Level in post-secondary education, however, the number of boys is significantly larger than girls, even though more girls than boys follow general post-secondary education. It is argued that the image of careers requiring Physics at advanced level (Engineering and Architecture) are male-oriented and girls tend to opt for other career paths, even within the sciences. Possible influences regarding the choice of science subjects are looked into in order to try to understand better why, even though officially there is the same possible access for girls into Physics courses, this is not taken up. There is, therefore, a need to promote these courses with girls.peer-reviewe

Beyond DICE : measuring the quality of a referring expression

This paper discusses ways in which the similarity between the contents of two referring expressions can be measured. Simi- larity metrics of this kind are essential when expressions gen- erated by an algoritm are compared against the ones produced by human speakers, for example as part of an experiment in which referring expressions are elicitated. We discuss argu- ments for and against different metrics, taking our departure from the well-known Dice metric.peer-reviewe

Generating plural NPs in discourse : evidence from the GNOME corpus

Research on the automatic generation of referring expressions has extended algorithms for the generation of full definite NPs to deal with anaphoric references. However, there has been relatively little work on the specific problems raised by plural anaphora. In particular, since plurals involve a reference to a set rather than an individual, one of the interesting questions concerns the extent to which elements of the set introduced by a plurality are salient, as compared to the plurality itself. This paper offers a preliminary exploration of these questions through a study of a small, richly annotated corpus. We discuss the implications of some of the findings for automatic referring expression generation, and also identify some fruitful avenues for future work.peer-reviewe

Attribute preference and priming in reference production : experimental evidence and computational modeling

Referring expressions (such as the red chair facing right) often show evidence of preferences (Pechmann, 1989; Belke & Meyer, 2002), with some attributes (e.g. colour) being more frequent and more often included when they are not required, leading to overspecified references. This observation underlies many computational models of Referring Expression Generation, especially those influenced by Dale & Reiter’s (1995) Incremental Algorithm. However, more recent work has shown that in interactive settings, priming can alter preferences. This paper provides further experimental evidence for these phenomena, and proposes a new computational model that incorporates both attribute preferences and priming effects. We show that the model provides an excellent match to human experimental data.peer-reviewe

Need I say more? On factors causing referential overspecification

We present the results of an elicitation experiment conducted to investigate which factors cause speakers to overspecify their referential expressions, where we hypothesized properties of the target and properties of the communicative setting to play a role. The results of this experiment show that speakers tend to provide more information when referring to a target in a more complex domain and when referring to plural targets. Moreover, written and spoken referring expressions do not differ in terms of redundancy, but do differ in terms of the number of words that they contain: speakers need more words to provide the same information as people who type their expressions.peer-reviewe

Intrinsic vs. extrinsic evaluation measures for referring expression generation

In this paper we present research in which we apply (i) the kind of intrinsic evaluation metrics that are characteristic of current comparative HLT evaluation, and (ii) extrinsic, human task-performance evaluations more in keeping with NLG traditions, to 15 systems implementing a language generation task. We analyse the evaluation results and find that there are no significant correlations between intrinsic and extrinsic evaluation measures for this task.peer-reviewe

Multimodal reference in dialogue : towards a balanced corpus

Generation of Referring Expressions (GRE), e.g., Dale and Reiter (1995), is one of the core tasks of Natural Language Generation (NLG) systems. Usually it is formulated as an identification problem: given a domain representing entities and their properties, construct a referring expression for a target referent or set of target referents which singles it out from its distractors. Recently, researchers in this area have turned their attention to multimodal referring acts, in particular, the interaction between the two modalities of pointing and describing – e.g., Kranstedt et al. (2006), Piwek (2007), and Van der Sluis and Krahmer (2007). Additionally, psycholinguistic work is increasingly investigating the conditions governing the use of pointing gestures as part of referring acts in dialogue, opposed to monologue. Here, we present the design of an experiment on multimodal reference in two-party dialogue. The purpose of the experiment is to create a corpus that can inform the development of multimodal GRE algorithms.peer-reviewe