Shared task proposal: Instruction giving in virtual worlds

This paper reports on the results of the working group “Virtual Environ-ments ” at the Workshop on Shared Tasks and Comparative Evaluation for NLG. This working group discussed the use of virtual environments as a platform for NLG evaluation, and more specifically of the generation of in

Generating Instructions in Virtual Environments (GIVE): A Challenge and an Evaluation Testbed for NLG

Would it be helpful or detrimental for the field of NLG to have a generally accepted competition? Competitions have definitely advanced the state of the art in some fields of NLP, but the benefits sometimes come at the price of over-competitiveness, and there is a danger of overfitting systems to the concrete evaluation metrics. Moreover, it has been argued that there are intrinsic difficulties in NLG that make it harder to evaluate than other NLP tasks (Scott and Moore, 2006)

Noun phrase generation for situated dialogs

We report on a study examining the generation of noun phrases within a spoken dialog agent for a navigation domain. The task is to provide real-time instructions that direct the user to move between a series of destinations within a large interior space. A subtask within sentence planning is determining what form to choose for noun phrases. This choice is driven by both the discourse history and spatial context features derived from the directionfollower’s position, e.g. his view angle, distance from the target referent and the number of similar items in view. The algorithm was developed as a decision tree and its output was evaluated by a group of human judges who rated 62.6 % of the expressions generated by the system to be as good as or better than the language originally produced by human dialog partners.

SCARE: A Situated Corpus with Annotated Referring Expressions

In this paper we report on the release of a corpus of English spontaneous instruction giving situated dialogs. The corpus was collected using the Quake environment, a first-person virtual reality game, and consists of pairs of participants completing a direction giver-direction follower scenario. The corpus contains the collected audio and video, as well as word-aligned transcriptions and the positional/gaze information of the player. Referring expressions in the corpus are annotated with the IDs of their virtual world referents. 1

Natural Noun Phrase Variation for Interactive Characters

Interactive characters that cohabit a shared space with human partners need to generate and interpret references to elements of the virtual world. Natural language allows for a wide range of phrasings for referring to any particular object, and this variation is thought to reflect not only spatial but also cognitive and linguistic factors. Our study attempts to account for the variability in referring forms found in a set of dialogs of two human partners performing a treasure-hunt task in a virtual world. A decision tree classifier was built that predicts the form of 51% of the referring expressions, compared to a baseline of 39% achieved by a heuristic classifier. The classification algorithm can be used by conversational characters to generate referring expressions of the appropriate form

Natural noun phrase variation for interactive characters

Interactive characters that cohabit a shared space with human partners need to generate and interpret references to elements of the virtual world. Natural language allows for a wide range of phrasings for referring to any particular object, and this variation is thought to reflect not only spatial but also cognitive and linguistic factors. Our study attempts to account for the variability in referring forms found in a set of dialogs of two human partners performing a treasure-hunt task in a virtual world. A decision tree classifier was built that predicts the form of 51 % of the referring expressions, compared to a baseline of 39 % achieved by a heuristic classifier. The classification algorithm can be used by conversational characters to generate referring expressions of the appropriate form

COMPARISON OF THE FRACTURE RESISTANCE OF ENDODONTICALLY TREATED TEETH RESTORED WITH DIRECT COMPOSITE RESTORATIONS VERSUS ENDOCROWNS- AN IN VITRO STUDY

Aim of the study The aim of the present study was to evaluate the compression resistance of endodontically treated teeth (ETT) restored by using two methods, direct composite restorations and indirect CAD/CAM endocrowns. Material and methods Endodontic treatment were performed on 10 extracted human teeth. After its completion, 5 teeth (Group 1) were restored with Tetric Ceram (Ivoclar Vivadent) composite direct restorations, and 5 with digitally scanned, designed, and milled TetricCAD (Ivoclar Vivadent) composite endocrowns (Group 2) adhesively cemented. Teeth were mechanically tested at compression with the help of a testing machine with an increasing force applied until samples’ fracture. The value of the force was registered for each sample, the means were calculated for each group and a statistical comparison analysis between groups was made. Results The fracture force applied on endocrowns was almost double than the one necessitated for the fracture of teeth restored with direct composite. Conclusions Endocrowns could be recommended as a solution for the restoration of ETT with significant loss of tooth structure due to their increased mechanical resistance

Incidence of severe critical events in paediatric anaesthesia (APRICOT): a prospective multicentre observational study in 261 hospitals in Europe

Background Little is known about the incidence of severe critical events in children undergoing general anaesthesia in Europe. We aimed to identify the incidence, nature, and outcome of severe critical events in children undergoing anaesthesia, and the associated potential risk factors. Methods The APRICOT study was a prospective observational multicentre cohort study of children from birth to 15 years of age undergoing elective or urgent anaesthesia for diagnostic or surgical procedures. Children were eligible for inclusion during a 2-week period determined prospectively by each centre. There were 261 participating centres across 33 European countries. The primary endpoint was the occurence of perioperative severe critical events requiring immediate intervention. A severe critical event was defined as the occurrence of respiratory, cardiac, allergic, or neurological complications requiring immediate intervention and that led (or could have led) to major disability or death. This study is registered with ClinicalTrials.gov, number NCT01878760. Findings Between April 1, 2014, and Jan 31, 2015, 31 127 anaesthetic procedures in 30 874 children with a mean age of 6.35 years (SD 4.50) were included. The incidence of perioperative severe critical events was 5.2% (95% CI 5.0-5.5) with an incidence of respiratory critical events of 3.1% (2.9-3.3). Cardiovascular instability occurred in 1.9% (1.7-2.1), with an immediate poor outcome in 5.4% (3.7-7.5) of these cases. The all-cause 30-day in-hospital mortality rate was 10 in 10 000. This was independent of type of anaesthesia. Age (relative risk 0.88, 95% CI 0.86-0.90; p<0.0001), medical history, and physical condition (1.60, 1.40-1.82; p<0.0001) were the major risk factors for a serious critical event. Multivariate analysis revealed evidence for the beneficial effect of years of experience of the most senior anaesthesia team member (0.99, 0.981-0.997; p<0.0048 for respiratory critical events, and 0.98, 0.97-0.99; p=0.0039 for cardiovascular critical events), rather than the type of health institution or providers. Interpretation This study highlights a relatively high rate of severe critical events during the anaesthesia management of children for surgical or diagnostic procedures in Europe, and a large variability in the practice of paediatric anaesthesia. These findings are substantial enough to warrant attention from national, regional, and specialist societies to target education of anaesthesiologists and their teams and implement strategies for quality improvement in paediatric anaesthesia