Risk Shift of Real Estate Stocks during the COVID-19 Pandemic

The outbreak of the COVID-19 pandemic induces an increase of risk in global equity markets where real estate stocks are often perceived as a ‘safe haven’. Employing the Fama and French’s (2015) five-factor model, we calculate the betas for risk factors and investigate the influence of market crises on excess returns of real estate stocks. The time series used in this study allows for splitting the data into two crisis periods namely the global financial crisis during 2007-2008 and the COVID-19 crisis in 2020. Our empirical evidence underlines that the undifferentiated view of real estate stocks as an overall ‘safe haven’ is not supported: 1) We find the risk factors of Fama and French can be applied to real estate stocks only to some extent, where the investment and profitability factors show opposite signs compared to general stocks; 2) Regional differences exist and Asian real estate markets show stronger diversification benefits during the crises; 3) Differences in business scopes lead to distinct reactions to the crises, where Asian firms focusing on real estate development and diversified activities are proven stronger during the COVID-19 pandemic and thus may offer better diversification value for investors; and 4) European real estate stocks are the worst-performing in terms of annualized return, specifically for firms offering real estate development and diversified activities. During both crisis periods, operating and services firms suffer a significant negative impact in Europe and are less likely to have diversification value

Risk Shift of Real Estate Stocks during the COVID-19 Pandemic

The outbreak of the COVID-19 pandemic induces an increase of risk in global equity markets where real estate stocks are often perceived as a ‘safe haven’. Employing the Fama and French’s (2015) five-factor model, we calculate the betas for risk factors and investigate the influence of market crises on excess returns of real estate stocks. The time series used in this study allows for splitting the data into two crisis periods namely the global financial crisis during 2007-2008 and the COVID-19 crisis in 2020. Our empirical evidence underlines that the undifferentiated view of real estate stocks as an overall ‘safe haven’ is not supported: 1) We find the risk factors of Fama and French can be applied to real estate stocks only to some extent, where the investment and profitability factors show opposite signs compared to general stocks; 2) Regional differences exist and Asian real estate markets show stronger diversification benefits during the crises; 3) Differences in business scopes lead to distinct reactions to the crises, where Asian firms focusing on real estate development and diversified activities are proven stronger during the COVID-19 pandemic and thus may offer better diversification value for investors; and 4) European real estate stocks are the worst-performing in terms of annualized return, specifically for firms offering real estate development and diversified activities. During both crisis periods, operating and services firms suffer a significant negative impact in Europe and are less likely to have diversification value

Determining and addressing obstacles to the effective use of long-lasting insecticide-impregnated nets in rural Tanzania

<p>Abstract</p> <p>Background</p> <p>The objective of this project was to achieve high, sustainable levels of net coverage in a village in rural Tanzania by combining free distribution of long-lasting insecticide-impregnated nets (LLINs) with community-tailored education. In Tanzania, malaria is the leading cause of morbidity and mortality. Although malaria bed nets have a well-established role in reducing disease burden, few rural households have access to nets, and effective use depends on personal practices and attitudes.</p> <p>Methods</p> <p>Five practices and attitudes inconsistent with effective LLIN use were identified from household interviews (n = 10). A randomized survey of villagers (n = 132) verified local prevalence of these practices and attitudes. Community leaders held an educational session for two members of every household addressing these practice and attitudes, demonstrating proper LLIN use, and emphasizing behaviour modification. Attendees received one or two LLINs per household. Surveys distributed three weeks (n = 104) and 15 months (n = 104) post-intervention assessed corrected practices and attitudes. Project efficacy was defined by correction of baseline practices and attitudes as well as high rates of reported daily net use, with statistical significance determined by chi-square test.</p> <p>Results</p> <p>Baseline interviews and surveys revealed incorrect practices and attitudes regarding 1) use of nets in dry season, 2) need to retreat LLINs, 3) children napping under nets, 4) need to repair nets, and 5) net procurement as a priority, with 53- 88.6% incorrect responses (11.4-47% correct responses). A three-week follow-up demonstrated 83-95% correct responses. Fifteen-month follow-up showed statistically significant (p < 0.01) corrections from baseline in all five practice and attitudes (39.4-93.3% correct answers). 89.4% of respondents reported using their nets every night, and 93.3% affirmed purchase of nets as a financial priority.</p> <p>Conclusions</p> <p>Results suggest that addressing community-specific practices and attitudes prior to LLIN distribution promotes consistent and correct use, and helps change attitudes towards bed nets as a preventative health measure. Future LLIN distributions can learn from the paradigm established in this project.</p

Saliency Map Verbalization: Comparing Feature Importance Representations from Model-free and Instruction-based Methods

Saliency maps can explain a neural model's predictions by identifying important input features. They are difficult to interpret for laypeople, especially for instances with many features. In order to make them more accessible, we formalize the underexplored task of translating saliency maps into natural language and compare methods that address two key challenges of this approach -- what and how to verbalize. In both automatic and human evaluation setups, using token-level attributions from text classification tasks, we compare two novel methods (search-based and instruction-based verbalizations) against conventional feature importance representations (heatmap visualizations and extractive rationales), measuring simulatability, faithfulness, helpfulness and ease of understanding. Instructing GPT-3.5 to generate saliency map verbalizations yields plausible explanations which include associations, abstractive summarization and commonsense reasoning, achieving by far the highest human ratings, but they are not faithfully capturing numeric information and are inconsistent in their interpretation of the task. In comparison, our search-based, model-free verbalization approach efficiently completes templated verbalizations, is faithful by design, but falls short in helpfulness and simulatability. Our results suggest that saliency map verbalization makes feature attribution explanations more comprehensible and less cognitively challenging to humans than conventional representations.Comment: ACL 2023 Workshop on Natural Language Reasoning and Structured Explanations (NLRSE

Free versus purchased mosquito net ownership and use in Budondo sub-county, Uganda.

BACKGROUND: While the distribution of mosquito bed nets is a widely adopted approach for malaria prevention, studies exploring how the usage of a net may be influenced by its source and other factors remain sparse. METHODS: A standardized questionnaire and home-visit observations were used to collect data from 9 villages in Budondo sub-county, Uganda in 2016. Household- and individual-level data were collected, such as bed net ownership (at least one net versus none), acquirement source (free versus purchased), demographics, as well as knowledge of malaria and preventative measures. Net-level data, including alternative uses, and bed net quantity and integrity, were also collected. Mixed effects logistic regression models were performed to identify the key determinants of bed net use. RESULTS: Overall, the proportion of households with at least one bed net was 40%, while bed net availability was only reported among 27% of all household members. Awareness of the benefits of bed net use was statistically significantly associated with ownership of at least one net (OR = 1.72, 95% CI 1.11-2.68, p = 0.02). Among those who own net(s), the odds of a bed net being correctly used (i.e., to sleep under) after adjusting for potential confounders were significantly lower for nets that were obtained free compared to nets that were purchased by the owners themselves (OR = 0.33, 95% CI 0.21-0.51, p < 0.01), resulting in an alternative use of the net. Other factors such as female gender, children ≤ 5 years old, and pregnancy status were also significantly associated with having a net to sleep under (all p < 0.01). CONCLUSION: Understanding inter- and intra-household net-use factors will help malaria control programmes more effectively direct their efforts to increase public health impact. Future studies may additionally consider socioeconomic status and track the lifetime of the net

A Rapid, Low-cost Methodology for Longitudinal Evaluation of Insecticide Treated Bednet Distributions: A Pilot Survey Coupling Bednet usage with Malaria Prevalence at the Household level

Tanzania’s National Malaria Control Program distributed 23.3 million insecticidetreated bed nets (ITNs) between 2009 and 2011. Annual randomized household surveys were conducted from 2009 to 2011 to assess the incremental effects of the distribution campaign on malaria prevalence and bednet usage in Kijumbura village in Kagera, Tanzania. Data was collected about household ITN ownership and individual use, and each household member was given a rapid malaria diagnostic test (RDT). In total, 1247 individuals from 285 households participated. From 2009 to 2011, household ITN ownership increased from 50.6 to 95.3% and individual usage increased from 9.7 to 55.3% in 2011. Malaria point prevalence decreased from 15.8% in 2009 to 6.5% in 2010, and increased from 6.5% in 2010 to 10.7% in 2011. The survey cost in 2011 was 23.50 USD per household; major expenses were transportation, personnel payment, and the purchase of the RDTs. Evaluations of bednet distribution programs generally rely on distribution data and selfreported net ownership, but it is important to also assess the goal endpoint of reduction in malaria prevalence. We show that this can be achieved quickly and cost-effectively through randomized surveys measuring bednet usage coupled with malaria prevalence at the household level

A comparison of Lenz lenses and LC resonators for NMR signal enhancement

High signal-to-noise ratio (SNR) of the NMR signal has always been a key target that drives massive research effort in many fields. Among several parameters, a high filling factor of the MR coil has proven to boost the SNR. In case of small-volume samples, a high filling factor and thus a high SNR can be achieved through miniaturizing the MR coil. However, under certain circumstances, this can be impractical. In this paper, we present an extensive theoretical and experimental investigation of the inductively coupled LC resonator and the magnetic Lenz lens as two candidate approaches that can enhance the SNR in such circumstances. The results demonstrate that the narrow-band LC resonator is superior in terms of SNR, while the non-tuned nature of the Lenz lens makes it preferable in broadband applications

Provenance of Oligocene–Miocene sedimentary rocks in the Cuu Long and Nam Con Son basins, Vietnam and early history of the Mekong River

The offshore Cuu Long (CLB) and Nam Con Son (NCSB) basins of SE Vietnam are two important Cenozoic hydrocarbon-bearing basins in the southern South China Sea (SCS), which can contribute to understanding the evolution of major SE Asian river systems, in particular the Mekong River. The Oligocene to Early Miocene basin fill of the Cuu Long Basin is dominated by sediment sourced locally from the Da Lat Zone basement on land. Sandstones have abundant Cretaceous detrital zircons and heavy mineral assemblages dominated by apatite and epidote. The Bach Ho Unconformity at c. 16 to 20.5 Ma marks a major provenance change and the overlying Middle to Late Miocene Con Son and Dong Nai formations were sourced by a large river system, which drained Indochina or even the Himalaya, resembling the present-day Mekong River. These formations have heterogeneous detrital zircon populations dominated by Triassic ages and zircon–rutile–tourmaline-dominated heavy mineral assemblages. The Oligocene Cau and Early Miocene Dua formations of the Nam Con Son Basin have a similar provenance to the CLB Con Son and Dong Nai formations, indicating a comparable drainage history of a large proto-Chao Phraya. At the Dua Unconformity at c. 15.4 to 17 Ma the Indochina provenance signature changes to a predominant Sibumasu signature. The early Mekong River evolution is suggested to have involved two river systems. A proto-Mekong 1 initially filled the CLB, while at the same time a proto-Chao Phraya River with a capture area into the Himalaya filled the Malay Basin and/or the NCSB. At the end of the Early Miocene drainage was completely reorganised, and the proto-Mekong 1 captured the headwaters of the proto-Chao Phraya and became the proto-Mekong 2, while the NCSB was filled by sediment from the Malay–Thai Peninsula. This major change marks a very important drainage reorganisation in the southern SCS region

A Selection of Benchmark Problems in Solid Mechanics and Applied Mathematics

In this contribution we provide benchmark problems in the field of computational solid mechanics. In detail, we address classical fields as elasticity, incompressibility, material interfaces, thin structures and plasticity at finite deformations. For this we describe explicit setups of the benchmarks and introduce the numerical schemes. For the computations the various participating groups use different (mixed) Galerkin finite element and isogeometric analysis formulations. Some programming codes are available open-source. The output is measured in terms of carefully designed quantities of interest that allow for a comparison of other models, discretizations, and implementations. Furthermore, computational robustness is shown in terms of mesh refinement studies. This paper presents benchmarks, which were developed within the Priority Programme of the German Research Foundation ‘SPP 1748 Reliable Simulation Techniques in Solid Mechanics—Development of Non-Standard Discretisation Methods, Mechanical and Mathematical Analysis’. © 2020, The Author(s)