Limit Theorems for Estimating the Parameters of Differentiated Product Demand Systems

We provide an asymptotic distribution theory for a class of Generalized Method of Moments estimators that arise in the study of differentiated product markets when the number of observations is associated with the number of products within a given market. We allow for three sources of error: the sampling error in estimating market shares, the simulation error in approximating the shares predicted by the model, and the underlying model error. The limiting distribution of the parameter estgimator is normal provided the size of the consumer sample and the number of simulation draws grow at a large enough rate relative to the number of products. The required rates differ for two frequently used demand models, and a small Monte Carlo study shows that the difference in asymptotic properties of the two models are reflected in the models' small sample properties. The differences impact directly on the computational burden of the two models.Choice models, Method of Moments, Multinominal, Random Coefficients, Vertical Model

Limit Theorems for Estimating the Parameters of Differentiated Product Demand Systems

We provide an asymptotic distribution theory for a class of Generalized Method of Moments estimators that arise in the study of differentiated product markets when the number of observations is associated with the number of products within a given market. We allow for three sources of error: the sampling error in estimating market shares, the simulation error in approximating the shares predicted by the model, and the underlying model error. The limiting distribution of the parameter estimator is normal provided the size of the consumer sample and the number of simulation draws grow at a large enough rate relative to the number of products. We specialise our distribution theory to the Berry, Levinsohn, and Pakes (1995) random coefficient logit model and a pure characteristic model. The required rates differ for these two frequently used demand models. A small Monte Carlo study shows that the difference in asymptotic properties of the two models are reflected in the models' small sample properties. These differences impact directly on the computational burden of the two models.Choice models, Method of moments, Random coefficients, Product differentiation

Limit Theorems for Estimating the Parameters of Differentiated Product Demand Systems

We provide an asymptotic distribution theory for a class of Generalized Method of Moments estimators that arise in the study of differentiated product markets when the number of observations is associated with the number of products within a given market. We allow for three sources of error: the sampling error in estimating market shares, the simulation error in approximating the shares predicted by the model, and the underlying model error. The limiting distribution of the parameter estimator is normal provided the size of the consumer sample and the number of simulation draws grow at a large enough rate relative to the number of products. We specialise our distribution theory to the Berry, Levinsohn, and Pakes (1995) random coefficient logit model and a pure characteristic model. The required rates differ for these two frequently used demand models. A small Monte Carlo study shows that the difference in asymptotic properties of the two models are reflected in the models’ small sample properties. These differences impact directly on the computational burden of the two models

The changing of representation for Female Professional Wrestlers in WWE (1980s-2010s)

This thesis aims to explore the representation of female wrestlers in WWE across a set period of time. The study aims to answer several research questions related to female wrestlers’ representation and how it changes. This is done by following two viewing methods inspired by Stuart Hall’s Theories of Representation. By analysing a specific match from a particular decade, the thesis aims to explore what changes for female wrestlers’ representation can be constructed from what is shown. By watching the same match again, but listening to the commentary, the thesis hopes to explore how the intentional representation from what the commentators are saying affects what has previously been seen. Both of these viewing methods also raise the question of whether any external influences affect female wrestlers representation. The aim of this thesis is to provide insight by comparing the analyses collected. The thesis hopes to demonstrate changes in specific areas such as costume, characterisation, dialogue, profession wrestling moves and the overall presentation of matches involving female wrestlers. The purpose is to help provide more insight into women’s professional wrestling in WWE, whilst also demonstrating how different viewing techniques of performance may affect how we interpret them

Attitudes to lesbian, gay, bisexual and transgender parents seeking health care for their children in two early parenting services in Australia

Aim: to examine the attitudes to and knowledge and beliefs about homosexuality, of nurses and allied professionals in two early parenting services in Australia. Background: Early parenting services employ nurses and allied professionals. Access and inclusion policies are important in community health and early childhood service settings. However, little is known about the perceptions of professionals who work within early parenting services in relation to lesbian, gay, bisexual and transgender families. Design: This is the final in a series of studies and was undertaken in two early parenting services in two states in Australia using a cross-sectional design with quantitative and qualitative approaches. Methods: Validated questionnaires were completed by 51 nurses and allied professionals and tested with Chi-squared test of independence (or Fisher’s exact test), Mann–Whitney U-test, Kruskal–Wallis one-way analysis of variance, or Spearman’s rank correlation. Thematic analysis examined qualitative data collected in a box for free comments. Results: Of the constructs measured by the questionnaires, no significant relationships were found in knowledge, attitude and gay affirmative practice scores by sociodemographic variables or professional group. However, attitude to lesbians and to gay men scores were significantly negatively affected by conservative political affiliation (p=0.038), held religious beliefs (p=0.011), and frequency of praying (p=0.018). Six overall themes were found: respect, parenting role, implications for the child, management, disclosure, resources and training. Conclusions: The study provided an in-depth analysis of the attitudes, knowledge and beliefs of professionals in two early parenting services, showing that work is needed to promote acceptance of diversity and the inclusion of LGBT families in planning, developing, evaluating and accessing early parenting services. Relevance to clinical practice: Access and inclusion plans for lesbian, gay, bisexual and transgender families are crucial in early parenting services in Australia and should be included in professional development programs

A study investigating a season\u27s baseball performance while wearing SportSight soft contact lenses

Background: The use of spectacles with colored lenses in sports is well known. Athletes have worn such colored lenses in an attempt to enhance their performance for a number of years with promising results. The integration of wavelength specific filters into contact lenses may provide significant performance enhancement as well as the visual advantages usually afforded by contact lenses relative to spectacles. Methods: A small group (N=5) of collegiate baseball players were fitted with SportSight soft contact lenses and were asked to wear them during practices and games for half of a season. The players\u27 batting and fielding statistics from the first and second halves of the season were compared to each other and to those of non-participating team members. All of the subjects were existing soft contact lens wearers. Results: The test group demonstrated dramatic improvements in batting statistics while wearing the SportSight lenses. Their percentage of statistical improvement in each category far surpassed that of non-participating team members. Conclusion: The results of this pilot study imply that wearing SportSight soft contact lenses yields marked performance enhancement for baseball players. Future studies involving larger subject pools are warranted to thoroughly evaluate the possible statistical significance of these findings

Comparative study of visual performance with tinted soft contact lenses vs. clear soft contact lenses and tinted spectacles under bright outdoor conditions; Phase II

Background: Research has clearly shown the advantages of performance tinted CL wear with regard to various measures of objective and subjective responses under various lighting conditions. The current study expanded upon these results. Methods: Subjects were 38 non-presbyopic emmetropes or slight ametropes with distance Snellen acuity of 20/20 or better while wearing -0.50 D spherical Acuvue 2 CLs. Measurements of 6m tachistoscopic stereoacuity and variable distance timed and tachistoscopic texture gradient recognition were obtained with subjects wearing clear CLs, tinted spectacles, and SportSight CLs. Lens modality and test sequence were randomized. Results: Stereoacuity results showed no statistically significant difference in stereolocalization when subjects were wearing clear CLs, SportSight CLs, or tinted spectacles. Texture gradient results using timed and tachistoscopic presentations demonstrated that it was more difficult for subjects to correctly identify the seam orientation at farther distances than nearer distances, and that subjects took more time to try to identify distant target orientation versus near target orientation. In addition, tachistoscopic presentations were not found to be significant with regard to correctness of responses at any distance with any lens modality. Subjective data indicated more physical comfort with either CL modality instead of tinted spectacles. SportSight CLs were also found to be the most visually comfortable modality, followed by tinted spectacles and then clear CLs. Furthermore, a general trend indicated that subjects felt they were able to perform best while wearing the SportSight CLs. This may partially be due to the fact that subjects noted fewer perceptions of stray light with SportSight CLs than with the other modalities. Likewise, subjects reported an equal number of perceived reflections while wearing SportSight CLs and clear CLs but significantly more while wearing tinted spectacles. Conclusion: Objective findings demonstrated that SportSight CLs provide similar performance with regard to distance depth perception and texture gradient recognition to tinted spectacles. Subjective data indicate that visual comfort of the SportSight CLs was superior to tinted spectacles and clear CLs. Additionally, a trend in subjective data demonstrated that the subjects perceived improved performance on the tests while wearing the SportSight CLs