The Use of One-, Two-, and Three-Parameter and Nominal Item Response Scoring in Place of Number-Right Scoring in the Presence of Test-Wiseness

Ability estimates yielded by the one- (1PL), two- (2PL), and three-parameter (3PL) models and the nominal response model (NRM) were compared with the number-right (NR) scoring model using items not susceptible to test-wiseness (NTW) and items susceptible to the ID1 test-wiseness strategy. These items were contained in grade 12 diploma examinations for social studies and chemistry. The results were compared for high-, middle-, and low-ability examinees. Differences were found between pairs of ability estimates obtained when 2PL, 3PL, and NRM scores were used in place of NR scores. The differences tended to be greater for chemistry than for social studies, and with the exception of high-ability students in social studies, for the subtest containing items with absurd options than for the subtest containing nonsusceptible test-wise items. It appears at least for the two subject areas considered in the present study, that the scoring models cannot be used interchangeably to obtain estimates of examinees’ abilities, particularly when a test contains test-wise susceptible items.En nous appuyant à la fois sur des items qui ne sont pas susceptibles d’être influencés par des paramètres de discrimination et de pseudo-chance, et à des items qui le sont, nous avons comparé les estimations de niveau d’habileté découlant de modèles à un (1PL), deux (2PL) et trois (3PL) paramètres ainsi que du modèle à réponses nominales (NRM) à celles provenant du modèle basé sur le nombre de bonnes réponses (NR). Ces items étaient présents dans les examens du ministère en études sociales et en chimie pour la 12e année. Nous avons comparé les résultats des élèves de différents niveaux d’habileté (bas, moyen et élevé). Des écarts se sont manifestés entre des paires d’estimations d’habileté quand nous avons analysé des scores reposant sur les modèles 2PL, 3PL et NRM plutôt que les scores NR. De façon générale, les différences étaient plus importantes: (a) en chimie qu’en études sociales et, (b) à l’exception des élèves à capacité élevée en études sociales, dans le sous-test comprenant des réponses absurdes que dans celui avec des items qui ne sont pas susceptibles d’être influencés par des paramètres de discrimination et de pseudo-chance. Du moins pour les deux domaines à l’étude, il semblerait que les modèles de pointage ne sont pas interchangeables dans l’évaluation des capacités des élèves, surtout lorsqu’un examen contient des items susceptibles d’être influencés par des paramètres de discrimination et de pseudo-chance

Pataphysical Networking: Virtuality, Potentiality and the Experimental Works of the Collège de 'Pataphysique, the Oulipo, and the Mouvement Panique

My dissertation investigates the Collège de Pataphysique, a little-known mid-20th century French artistic movement, and two related groups, the Oulipo (Workshop of Potential Literature) and the Mouvement Panique. The imaginary science of pataphysics was invented in 1893 by Alfred Jarry who argued that existing scientific laws only offered a limited number of possible explanations for worldly phenomena. The notion of pataphysics was picked up by the Collège in 1948, and its practitioners advocated the exploration of alternative approaches to reality through artistic and experimental means. Scholars have tended to ignore the Collège’s influence on 20th century French art and culture, preferring instead to treat its most famous practitioners, such as Raymond Queneau and Boris Vian, in isolation rather than as members of the pataphysical network. My dissertation contests dismissals of the Collège’s importance by reconstructing its long-occluded artistic genealogy and tracking its connections and ongoing cultural activities. Such an examination shows why pataphysical methods and modes of work might be relevant in contemporary intellectual and artistic contexts. My first chapter traces the history of the Collège de Pataphysique. I examine the Collège’s founding documents and literary texts by pataphysicians, Raymond Queneau, Boris Vian and René Clair, demonstrating how they implement pataphysical philosophy in the process of creation. The second chapter focuses on the Oulipo and three of its writers, Georges Perec, Italo Calvino and Marcel Bénabou, who use literature to experiment with potentiality and virtuality. The third chapter describes the case of the Mouvement Panique, and through films of its founders, Fernando Arrabal and Alejandro Jodorowsky, demonstrates that the cultivation of pataphysics is not limited to literature and can be realized in cinema. In the final chapter I look at the Collège’s contemporary publications and activities in order to draw conclusions about the growth of the pataphysical network and its importance for today’s arts and sciences

CD248 expression on mesenchymal stromal cells is required for post-natal and infection-dependent thymus remodelling and regeneration

The role of mesenchymal stromal cells (MSCs) in regulating immune responses in the thymus is currently unclear. Here we report the existence and role of a MSC population in the thymus that expresses the pericyte and MSC marker CD248 (endosialin). We show using a CD248-deficient mouse model, that CD248 expression on these cells is required for full post-natal thymus development and regeneration post-Salmonella infection. In CD248 -/- mice the thymus is hypocellular and regeneration is poorer, with significant loss of all thymocyte populations. This identifies the requirement of CD248 to maintain optimal thymic cellularity post-partum and infection