We study the long-run evolution of brand preferences, using new data on consumers' life histories and purchases of consumer packaged goods. Variation in where consumers have lived in the past allows ...us to isolate the causal effect of past experiences on current purchases, holding constant contemporaneous supply-side factors. We show that brand preferences form endogenously, are highly persistent, and explain 40 percent of geographic variation in market shares. Counterfactuals suggest that brand preferences create large entry barriers and durable advantages for incumbent firms and can explain the persistence of early-mover advantage over long periods.
This paper develops a framework for measuring "tipping"-the increase in a firm's market share dominance caused by indirect network effects. Our measure compares the expected concentration in a market ...to the hypothetical expected concentration that would arise in the absence of indirect network effects. In practice, this measure requires a model that can predict the counterfactual market concentration under different parameter values capturing the strength of indirect network effects. We build such a model for the case of dynamic standards competition in a market characterized by the classic hardware/software paradigm. To demonstrate its applicability, we calibrate it using demand estimates and other data from the 32/64-bit generation of video game consoles, a canonical example of standards competition with indirect network effects. In our example, we find that indirect network effects can lead to a strong, economically significant increase in market concentration. We also find important roles for beliefs on both the demand side, as consumers tend to pick the product they expect to win the standards war, and on the supply side, as firms engage in penetration pricing to invest in growing their networks.
We document evidence of a persistent “early entry” advantage for brands in 34 consumer packaged goods industries across the 50 largest U.S. cities. Current market shares are higher in markets closest ...to a brand’s historic city of origin than in those farthest. For six industries, we know the order of entry among the top brands in each of the markets. We find an early entry effect on a brand’s current market share and perceived quality across U.S. cities. The magnitude of this effect typically drives the rank order of market shares and perceived quality levels across cities.
We describe the industrial market structure of CPG categories. The analysis uses a unique database spanning 31 consumer package goods (CPG) categories, 39 months, and the 50 largest US metropolitan ...markets. We organize our description of market structure around the notion that firms can improve brand perceptions through advertising investments, as in Sutton’s endogenous sunk cost theory. The richness of our data allow us to go beyond Sutton’s bounds test and to study the underlying forces bounding concentration away from zero. Observed advertising levels escalate in larger US markets. At the same time, the number of advertised brands in an industry appears to be invariant to market size. Therefore, the size-distribution of brands across markets is characterized by bigger (i.e. more heavily advertised) as opposed to more brands in larger markets. Correspondingly, observed concentration levels in advertising-intensive industries are bounded away from zero irrespective of market size.
Evidence suggests a role for excessive inflammation in COVID-19 complications. Colchicine is an oral anti-inflammatory medication beneficial in gout, pericarditis, and coronary disease. We aimed to ...investigate the effect of colchicine on the composite of COVID-19-related death or hospital admission.
The present study is a phase 3, randomised, double-blind, adaptive, placebo-controlled, multicentre trial. The study was done in Brazil, Canada, Greece, South Africa, Spain, and the USA, and was led by the Montreal Heart Institute. Patients with COVID-19 diagnosed by PCR testing or clinical criteria who were not being treated in hospital were eligible if they were at least 40 years old and had at least one high-risk characteristic. The randomisation list was computer-generated by an unmasked biostatistician, and masked randomisation was centralised and done electronically through an automated interactive web-response system. The allocation sequence was unstratified and used a 1:1 ratio with a blocking schema and block sizes of six. Patients were randomly assigned to receive orally administered colchicine (0·5 mg twice per day for 3 days and then once per day for 27 days thereafter) or matching placebo. The primary efficacy endpoint was the composite of death or hospital admission for COVID-19. Vital status at the end of the study was available for 97·9% of patients. The analyses were done according to the intention-to-treat principle. The COLCORONA trial is registered with ClinicalTrials.gov (NCT04322682) and is now closed to new participants.
Trial enrolment began in March 23, 2020, and was completed in Dec 22, 2020. A total of 4488 patients (53·9% women; median age 54·0 years, IQR 47·0–61·0) were enrolled and 2235 patients were randomly assigned to colchicine and 2253 to placebo. The primary endpoint occurred in 104 (4·7%) of 2235 patients in the colchicine group and 131 (5·8%) of 2253 patients in the placebo group (odds ratio OR 0·79, 95·1% CI 0·61–1·03; p=0·081). Among the 4159 patients with PCR-confirmed COVID-19, the primary endpoint occurred in 96 (4·6%) of 2075 patients in the colchicine group and 126 (6·0%) of 2084 patients in the placebo group (OR 0·75, 0·57–0·99; p=0·042). Serious adverse events were reported in 108 (4·9%) of 2195 patients in the colchicine group and 139 (6·3%) of 2217 patients in the placebo group (p=0·051); pneumonia occurred in 63 (2·9%) of 2195 patients in the colchicine group and 92 (4·1%) of 2217 patients in the placebo group (p=0·021). Diarrhoea was reported in 300 (13·7%) of 2195 patients in the colchicine group and 161 (7·3%) of 2217 patients in the placebo group (p<0·0001).
In community-treated patients including those without a mandatory diagnostic test, the effect of colchicine on COVID-19-related clinical events was not statistically significant. Among patients with PCR-confirmed COVID-19, colchicine led to a lower rate of the composite of death or hospital admission than placebo. Given the absence of orally administered therapies to prevent COVID-19 complications in community-treated patients and the benefit of colchicine in patients with PCR-proven COVID-19, this safe and inexpensive anti-inflammatory agent could be considered for use in those at risk of complications. Notwithstanding these considerations, replication in other studies of PCR-positive community-treated patients is recommended.
The Government of Quebec, the Bill & Melinda Gates Foundation, the National Heart, Lung, and Blood Institute of the US National Institutes of Health, the Montreal Heart Institute Foundation, the NYU Grossman School of Medicine, the Rudin Family Foundation, and philanthropist Sophie Desmarais.
Working Paper No. 25215 A long literature has developed econometric methods for estimating individual-consumer-level demand systems that accommodate corner solutions. The increasing access to ...transaction-level customer purchase histories across a wide array of markets and industries vastly expands the prospect for improved customer insight, more targeted marketing policies and individualized welfare analysis. A descriptive analysis of a broad, CPG database indicates that most consumer brand categories offer a wide variety of differentiated offerings for consumers. However, consumers typically purchase only a limited scope of the available variety, leading to a very high incidence of corner solutions which poses computational challenges for demand modeling. Historically, these computational challenges have limited the applicability of microeconometric models of demand in practice, except for the special case of pure discrete choice (e.g., logit and probit). Recent advances in computing power along with methods for numerical and simulation-based integration have been instrumental in facilitating the broader use of these models in practice. We survey herein the extant literature on the neoclassical derivation of microeconometric demand models that allow for corner solutions and differentiated products. We summarize the key developments in the literature, including the role of consumers’ price expectations, and point towards opportunities for future research.
Abstract
Aims
Inflammation plays an important role in cardiovascular disease (CVD) development. The NOD-like receptor protein-3 (NLRP3) inflammasome contributes to the development of atherosclerosis ...in animal models. Components of the NLRP3 inflammasome pathway such as interleukin-1β can therapeutically be targeted. Associations of genetically determined inflammasome-mediated systemic inflammation with CVD and mortality in humans are unknown.
Methods and results
We explored the association of genetic NLRP3 variants with prevalent CVD and cardiovascular mortality in 538 167 subjects on the individual participant level in an explorative gene-centric approach without performing multiple testing. Functional relevance of single-nucleotide polymorphisms on NLRP3 inflammasome activation has been evaluated in monocyte-enriched peripheral blood mononuclear cells (PBMCs). Genetic analyses identified the highly prevalent (minor allele frequency 39.9%) intronic NLRP3 variant rs10754555 to affect NLRP3 gene expression. rs10754555 carriers showed significantly higher C-reactive protein and serum amyloid A plasma levels. Carriers of the G allele showed higher NLRP3 inflammasome activation in isolated human PBMCs. In carriers of the rs10754555 variant, the prevalence of coronary artery disease was significantly higher as compared to non-carriers with a significant interaction between rs10754555 and age. Importantly, rs10754555 carriers had significantly higher risk for cardiovascular mortality during follow-up. Inflammasome inducers (e.g. urate, triglycerides, apolipoprotein C3) modulated the association between rs10754555 and mortality.
Conclusion
The NLRP3 intronic variant rs10754555 is associated with increased systemic inflammation, inflammasome activation, prevalent coronary artery disease, and mortality. This study provides evidence for a substantial role of genetically driven systemic inflammation in CVD and highlights the NLRP3 inflammasome as a therapeutic target.
Graphical Abstract
rs10754555 associates with higher NLRP3 mRNA expression and NLRP3 inflammasome activation, which induces the release of IL-1β and IL-18. This leads to systemic inflammation, higher risk for coronary artery disease, and cardiovascular mortality.
A long literature has developed econometric methods for estimating individual-consumer-level demand systems that accommodate corner solutions. The increasing access to transaction-level customer ...purchase histories across a wide array of markets and industries vastly expands the prospect for improved customer insight, more targeted marketing policies and individualized welfare analysis. A descriptive analysis of a broad, CPG database indicates that most consumer brand categories offer a wide variety of differentiated offerings for consumers. However, consumers typically purchase only a limited scope of the available variety, leading to a very high incidence of corner solutions which poses computational challenges for demand modeling. Historically, these computational challenges have limited the applicability of microeconometric models of demand in practice, except for the special case of pure discrete choice (e.g., logit and probit). Recent advances in computing power along with methods for numerical and simulation-based integration have been instrumental in facilitating the broader use of these models in practice. We survey herein the extant literature on the neoclassical derivation of microeconometric demand models that allow for corner solutions and differentiated products. We summarize the key developments in the literature, including the role of consumers’ price expectations, and point towards opportunities for future research.
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