Two-Method Planned Missing Designs for Longitudinal Research

We examine longitudinal extensions of the two-method measurement design, which uses planned missingness to optimize cost-efficiency and validity of hard-to-measure constructs. These designs use a combination of two measures: a “gold standard” that is highly valid but expensive to administer, and an inexpensive (e.g., survey-based) measure that contains systematic measurement bias (e.g., response bias). Using simulated data on four measurement occasions, we compared the cost-efficiency and validity of longitudinal designs where the gold standard is measured at one or more measurement occasions. We manipulated the nature of the response bias over time (constant, increasing, fluctuating), the factorial structure of the response bias over time, and the constraints placed on the latent variable model. Our results showed that parameter bias is lowest when the gold standard is measured on at least two occasions. When a multifactorial structure was used to model response bias over time, it is necessary to have the “gold standard” measures included at every time point, in which case most of the parameters showed low bias. Almost all parameters in all conditions displayed high relative efficiency, suggesting that the 2-method design is an effective way to reduce costs and improve both power and accuracy in longitudinal research

Starfish: Maria Irene Fornes and the Feminist Rewriting of Melodrama

Desde sus comienzos Fornes ha mostrado un interés por reescribir y parodiar las convenciones del melodrama romántico, en concreto la interrelación de fuerzas implícitas en el triángulo amoroso donde la heroína es siempre objeto del deseo masculino y adhesivo moral de la familia. The Successful Life of 3, Molly’s Dream, Sarita, The Conduct of Life y Mud subvierten, en mayor o menor medida y desde diferentes contrafórmulas teatrales, la dinámica de los géneros. En Mud Fornes consigue crear un «contradiscurso» (Foucault, 1978) en el que se cuestiona el rol femenino mediante la reapropiación de la imagen surrealista de la estrella de mar del cortometraje L’étoile de mer (1928) de Man Ray. El objetivo implícito en la epistemología fornesiana es romper la visión masculina de la mujer como objeto de deseo fetichista y diosa castradora (vagina dentata). Mae, la protagonista, no solo contradice las señas de identidad y el código de actuación que los dos hombres esperan de ella: madre, hermana y mujer a un tiempo. Su deseo final de abandonar el hogar plantea la posibilidad de un mundo sin hombres, donde la búsqueda del conocimiento se convierte en la nueva meta.Since her debut as a playwright in the 1960s, Fornes has always shown an interest in rewriting and parodying the conventions of romance melodrama, mostly the clash of forces found in the love triangle, and the role of the heroine as the object of masculine desire and the moral adhesive of the family. The Successful Life of 3, Molly’s Dream, Sarita, The Conduct of Life, and Mud subvert the status quo of gender relations by using a plethora of popular theatrical formulas. Mud can be analyzed as a «reverse discourse» (Foucault, 1978) insofar as it makes use of the old melodrama tropes and images. The reappropriation of Man Ray’s surrealist image of the starfish as used in L’étoile de mer (1928) is a clear example of Fornes’ feminist epistemology: by representing Mae’s identity in the negative male vocabulary, the playwright is producing a new narrative of the female self which is at odds with the patriarchal model of femininity. Far from embodying the vagina dentata (the castrating femme fatale), Mae stops being and doing what Lloyd and Henry expect from her. Her final desire to abandon the house raises the possibility of building up a new world where the quest for knowledge becomes the new guide to womanhood

Chern-Simons action for inhomogeneous Virasoro group as an extension of three dimensional flat gravity

We initiate the study of a Chern-Simons action associated to the semi-direct sum of the Virasoro algebra with its coadjoint representation. This model extends the standard Chern-Simons formulation of three dimensional flat gravity and is similar to the higher-spin extension of three dimensional anti-de Sitter or flat gravity. The extension can also be constructed for the exotic but not for the cosmological constant deformation of flat gravity.Comment: 15 pages. Version to appear in J. of Math. Phy