Grocery store records reveal London food deserts
Peer-Reviewed Publication
Updates every hour. Last Updated: 11-Nov-2025 00:11 ET (11-Nov-2025 05:11 GMT/UTC)
A new study identified large clusters of food deserts, where residents have limited access to affordable, nutritious food, in East London—particularly Newham, Redbridge, and Barking and Dagenham—and in parts of west London such as Ealing and Brent. The findings were published November 6th in the open-access journal PLOS Complex Systems by Tayla Broadbridge of the University of Nottingham, UK, and colleagues.
Diagnostic testing is big business. The global market for testing semiconductors for defects is estimated at $39 billion in 2025. For medical lab tests, the market is even bigger: $125 billion.
Both kinds of tests have something in common, says Rohan Ghuge, assistant professor of decision science in the information, risk, and operations management department at Texas McCombs. They involve complex systems with vast numbers of components, whether they’re evaluating computer chips or human bodies.
New research from Texas McCombs suggests a new approach to testing complex systems that might save time by eliminating some unnecessary and expensive steps.
Collaborating with competitors may sound counterintuitive, but it can also be the key to international success. The coopetition arrangement is not uncommon in the automotive sector, where rival brands share production lines or jointly develop vehicle models to reduce costs and speed up innovation. In his doctoral dissertation at the University of Vaasa, Finland, Shuwei Jiang reveals that the same logic applies to European SMEs as well – particularly those aiming to enter the Chinese market. Jiang’s dissertation not only discusses the benefits of coopetition but also identifies its risks and the mechanisms that help firms address them.
Abstract
Purpose – We aim to examine two issues. First, we intend to identify the best performing expected return proxies. Second, we investigate whether the expected return proxies for individual stocks can track the corresponding realized returns during extremely good or extremely bad times of the economic environment related to business conditions, stock market valuation and broad market performance.
Design/methodology/approach – We construct four sets of expected return proxies, including: (1) characteristic-based proxies; (2) standard risk-factor-based proxies; (3) risk-factor-based proxies that allow betas to vary with firm characteristics and (4) macroeconomic-variable-based proxies. First, we estimate expected returns for individual stocks using newly developed methods and evaluate the performance of these expected return proxies based on the minimum variance criterion of Lee et al. (2020). Second, we regress expected return proxies and realized returns on indicator variables that capture the extreme phases of the economic environment. Then we compare the estimated coefficients from these two sets of regressions and see if they are similar in magnitude via formal hypothesis testing.
Findings – We find that characteristic-based proxies and risk-factor-based proxies that allow betas to vary with firm characteristics are the two best performing proxies. Therefore, it is important to allow betas to vary with firm characteristics in constructing expected return proxies. We also find that model-based expected return proxies do a reasonably good job capturing actual returns during extremely bad and extremely good phases of business cycles measured by leading economic indicators, consumer confidence and business confidence. However, there is a large gap between the adjustment of model-based expected returns and realized returns during extreme episodes of stock market valuation or broad market performance.
Originality/value – We examine four types of expected return proxies and use the newly developed methodology in Lee et al. (2020) to see which one is the best. In addition, we document whether model-based expected returns from individual stocks adjust partially or fully to keep pace with actual returns in response to changing economic conditions. No prior studies have examined these two issues.
In 401(k) plans, one of the attractions has always been that employees choose where to invest their retirement funds. The average plan offers 28 options, according to the Investment Company Institute.
Employees might assume those options are picked to serve their best interests. But new research from Clemens Sialm, professor of finance at Texas McCombs, suggests they’re also serving someone else’s interests. Many funds are paying plan administrators to include them in a plan’s menu, a practice called revenue-sharing.
The result: Without knowing it, employees may be offered funds with higher fees and lower performance.