David Bell

Bio: David Bell is an academic researcher from University of Leeds. The author has contributed to research in topics: Tourism & Queer. The author has an hindex of 52, co-authored 214 publications receiving 14873 citations. Previous affiliations of David Bell include University of California, Los Angeles & Staffordshire University.

Recovering SKU-level Preferences and Response Sensitivities from Market Share Models Estimated on Item Aggregates

Abstract: We propose an alternative approach to obtaining SKU-level preferences and response sensitivities. An attribute-level model in which the unit of analysis is the market share for an alternative created by aggregation e.g., Colgate toothpaste) is distinguished from a truly disaggregate SKU-level model and develop an analytical relationship between parameters obtained from these two models is established. We show that the researcher can recover SKU-level parameters via calculation from estimated attribute-level parameters, circumventing the need for direct estimation of the more complex true SKU-level model. Our market share model is calibrated using 98 weeks of data for 10 brands and 168 SKUs in the toothpaste category. We show that instead of estimating 168 preference parameters (when we have an outside alternative in addition to the 168 inside ones), one need only estimate 10 brand preference parameters from which the 168 parameters can be computed as long as share and marketing mix data are available at the SKU level. Marketing mix response parameters can be recovered in a similar fashion. Estimation on holdout samples demonstrates superior predictive performance compared with other available methods. Implications for the derivation of SKU-level elasticities and forecasts of market share and response sensitivity for new items introduced to the category are discussed.

Neighborhood Social Capital and Social Learning for Experience Attributes of Products

Abstract: Social learning can occur when information is transferred from existing customers to potential customers. It is especially important when the information that is conveyed pertains to experience attributes, i.e., attributes of products that cannot be fully verified prior to the first purchase. Experience attributes are prevalent and salient when consumers shop through catalogs, on home shopping networks, and over the Internet. Firms therefore employ creative and sometimes costly methods to help consumers resolve uncertainty; we argue that uncertainty can be partially resolved through social learning processes that occur naturally and emanate from local neighborhood characteristics. Using data from Bonobos, a leading U.S. online fashion retailer, we find not only that local social learning facilitates customer trial but also that the effect is economically important because about half of all trials were partially attributable to it. Merging data from the Social Capital Community Benchmark Survey, we find that neighborhood social capital, i.e., the propensity for neighbors to trust each other and communicate with each other, enhances the social learning process and makes it more efficient. Social capital does not operate on trials directly; rather, it improves the learning process and therefore indirectly drives sales when what is communicated is favorable.

Cost-Effectiveness of Single Versus Multifraction SABR for Pulmonary Oligometastases: The SAFRON II Trial.

Abstract: The use of stereotactic ablative body radiation therapy (SABR) in advanced cancer care is increasing, yet the cost-effectiveness of single-fraction (SF) versus multifraction (MF) SABR in pulmonary oligometastases is unknown.A prespecified cost-effectiveness analysis was conducted of the Trans Tasman Radiation Oncology Group 13.01 - SAFRON II - randomized trial comparing SF with MF SABR in 87 patients with 133 pulmonary oligometastases. A partitioned survival model assessed costs and quality-adjusted life-years (QALY) over the within-trial period (4 years) and longer-term (10 years). Costs reflected a societal perspective, expressed in Australian dollars (A$) using 2020 prices and were estimated using patient level data on health care utilization for radiation therapy (including patient time), post-radiation systemic therapy and treatment of adverse effects. Quality of life was assessed using the EuroQoL EQ-5D-5L. The incremental cost-effectiveness ratio (ICER) was expressed as the cost per QALY gained for SF versus MF SABR, with uncertainty assessed using deterministic and probabilistic sensitivity analyses.SF cost less than MF for initial therapy (difference of A$1194/patient). Mean time to initiation of systemic drug therapy did not differ between arms (P = .94). Numerical differences in survival favoring SF resulted in greater overall health care use for the within-trial period. The within-trial ICER was A$15,821/QALY and A$23,265/QALY over the longer term. Results were most sensitive to the cost of postprogression therapies and utility values. The sensitivity analysis indicated that SF SABR has a 97% probability of being cost-effective at a willingness-to-pay of A$50,000/QALY.SF has lower initial costs and is highly likely to be cost-effective. Time to initiation of systemic therapy associated with disease progression is highly patient relevant and is a major driver of cost-effectiveness. Comparisons for SF SABR with nonradiation therapy approaches to the treatment of pulmonary oligometastases warrant further investigation.

Bowling alone: The collapse and revival of American community

Abstract: The present historical moment may seem a particularly inopportune time to review Bowling Alone, Robert Putnam's latest exploration of civic decline in America. After all, the outpouring of volunteerism, solidarity, patriotism, and self-sacrifice displayed by Americans in the wake of the September 11 terrorist attacks appears to fly in the face of Putnam's central argument: that \"social capital\" -defined as \"social networks and the norms of reciprocity and trustworthiness that arise from them\" (p. 19)'has declined to dangerously low levels in America over the last three decades. However, Putnam is not fazed in the least by the recent effusion of solidarity. Quite the contrary, he sees in it the potential to \"reverse what has been a 30to 40-year steady decline in most measures of connectedness or community.\"' As an example of how the current \"war on terrorism\" could generate a durable civic renewal, Putnam points to the burst in civic practices that occurred during and after World War II, which he says \"permanently marked\" the generation that lived through it and had a \"terrific effect on American public life over the last half-century.\" 3 If Americans can follow this example and channel their current civic

Economics of Information

Abstract: The author systematically examines one of the important issues of information — establishing the market price. He introduces the concept of «search» — where a buyer wanting to get a better price, is forced to question sellers. The article deals with various aspects of finding the necessary information.

Boundary-Work and the Demarcation of Science from Non-Science: Strains and Interests in Professional Ideologies of Scientists

Abstract: The demarcation of science from other intellectual activities-long an analytic problem for philosophers and sociologists-is here examined as a practical problem for scientists. Construction of a boundary between science and varieties of non-science is useful for scientists' pursuit of professional goals: acquisition of intellectual authority and career opportunities; denial of these resources to "pseudoscientists"; and protection of the autonomy of scientific research from political interference. "Boundary-work" describes an ideological style found in scientists' attempts to create a public image for science by contrasting it favorably to non-scientific intellectual or technical activities. Alternative sets of characteristics available for ideological attribution to science reflect ambivalences or strains within the institution: science can be made to look empirical or theoretical, pure or applied. However, selection of one or another description depends on which characteristics best achieve the demarcation in a way that justifies scientists' claims to authority or resources. Thus, "science" is no single thing: its boundaries are drawn and redrawn inflexible, historically changing and sometimes ambiguous ways.