The Market for Television Advertising: Model and Evidence

We provide a model of television advertising based on an explicit characterization of an advertisement's contribution to an advertiser's profits that suggests that each program faces a downward sloping demand for its ad time. Hence Fournier and Martin's (1983) "law of one price" does not hold in our model. We study these contrasting arguments about television advertising by examining the pricing of broadcast network advertising. In conducting this empirical examination we encounter and solve a severe multicollinearity problem. We conclude that the evidence supports the advertising model presented in this paper and demonstrates segmentation between cable and broadcast viewers in the national television advertising market.broadcast, cable, market segmentation, multicollinearity,

Intervention In Kosovo: Legal? Effective?

A retrospective look at the 1999 war in Kosovo is in orde

The Multitude of Molecular Hydrogen Knots in the Helix Nebula

We present HST/NICMOS imaging of the H_2 2.12 \mu m emission in 5 fields in the Helix Nebula ranging in radial distance from 250-450" from the central star. The images reveal arcuate structures with their apexes pointing towards the central star. Comparison of these images with comparable resolution ground based images reveals that the molecular gas is more highly clumped than the ionized gas line tracers. From our images, we determine an average number density of knots in the molecular gas ranging from 162 knots/arcmin^2 in the denser regions to 18 knots/arcmin^2 in the lower density outer regions. Using this new number density, we estimate that the total number of knots in the Helix to be ~23,000 which is a factor of 6.5 larger than previous estimates. The total neutral gas mass in the Helix is 0.35 M_\odot assuming a mass of \~1.5x10^{-5} M_\odot for the individual knots. The H_2 intensity, 5-9x10^{-5} erg s^{-1} cm^{-2} sr^{-1}, remains relatively constant with projected distance from the central star suggesting a heating mechanism for the molecular gas that is distributed almost uniformly in the knots throughout the nebula. The temperature and H_2 2.12 \mu m intensity of the knots can be approximately explained by photodissociation regions (PDRs) in the individual knots; however, theoretical PDR models of PN under-predict the intensities of some knots by a factor of 10.Comment: 26 pages, 3 tables, 10 figures; AJ accepte

Technology and Textile Mill Architecture in Canada

Textile mills evolved as a distinct architectural type in the late eighteenth and early nineteenth centuries. To a large extent their long, narrow, high form was determined by the needs to distribute power by mechanical means from a central source and to provide good lighting for spinning and weaving. Mills were susceptible to fire. To reduce the risk of fire British mill engineers developed the fireproof mill design in which flammable materials were replaced with cast iron and brick wherever possible. American engineers developed the slow-burning mill design in which heavy-timber construction, isolation of potential fires and efficient fire-fighting systems were designed to slow the spread of fire and allow effective fire fighting. When Canada's textile industry began to expand in the 1870s it adopted the slow-burning method of construction. By the early twentieth century changes in power transmission systems and lighting systems had made the old mill form obsolete. New building materials had made both slow-burning and fireproof mill construction obsolete. However, economic conditions limited new building programs and many of the old mills remained in use until the second half of the twentieth century. Résumé Les filatures ont donné naissance à un type d'architecture distinct à la fin du XVIIIe et au début du XIXe siècle. La forme de ces hauts bâtiments étroits et longs était déterminée par la nécessité d'y distribuer la force motrice par des moyens mécaniques à partir d'une source centrale et d'assurer un bon éclairage pour le filage et le tissage. Les risques d'incendie qui menaçaient constamment les filatures britanniques ame-nèrent les ingénieurs chargés d'en concevoir les plans à développer un modèle de filature à l'épreuve du feu, en remplaçant les matériaux inflammables par de la fonte et de la brique partout où cela était possible. Dans le même esprit, les ingénieurs américains mirent au point un modèle de filature aux matériaux peu combustibles à propos duquel l'ossature en gros madriers, l'isolation des sources possibles d'incendies et des systèmes efficaces pour les combattre concouraient à ralentir la propagation du feu et à faciliter le travail des pompiers. Quand l'industrie textile prit son essor au Canada dans les années 1870, on adopta la méthode des matériaux peu combustibles pour la construction des filatures. Au début du XXe siècle, avec l'évolution des systèmes d'éclairage et de transmission de l'énergie, l'ancienne architecture des filatures n'avait plus sa raison d'être. L'utilisation de nouveaux matériaux de construction rendait le modèle de filature à l'épreuve du feu et le modèle aux matériaux peu combustibles complètement dépassés. Mais la situation économique ne se prêtait guère à l'érection de nouveaux bâtiments et beaucoup des an-ciennes filatures sont restées en service jusqu 'à la seconde moitié du XXe siècle

“Este diablo de vieja”: Revealing the Conversa Voice in Celestina

Due to the extraordinary socio-religious situation of the Inquisition’s aggressive attempt at unification looming over late Medieval Spain, the existence of a converso influence in Fernando de Rojas’ masterpiece, Celestina, is rarely up for debate. However, the way in which this influence manifests itself in Rojas’ only known work remains open for discussion among scholars of the work. Despite critics who struggle to view Celestina as an expression of converso literature, arguments have been made to establish the likelihood of converso status for Pleberio, Calisto, and Melibea, but have yet to look profoundly to Celestina’s own origins. Thanks to her perceived magical abilities, the famous go-between operates within the parody of religion and its relation to courtly love. Parody and irony function as instruments that create a space for the traditionally marginalized voices rendered by the Spanish sentimental romance to be heard, notably due to gender and cultural Christian values. Interpreting Celestina as both a conversa who deviates from the proper Christian way of life and as a deviant from established gender roles further expands the realm of ironic possibilities offered by the sentimental romance genre and furthers the humoristic nature of the religious parody throughout the work. Furthermore, the transgressive nature of converso literature challenges Spanish conventional values related to blood purity and serves as social criticism rather than as condemnations of deviant behavior. This reconsideration of Celestina as a conversa voice expands the possibilities of understanding Rojas’ contribution to the sentimental romance genre