Large Stocks Research Articles

Modeling clustered binary data with nonparametric unobserved heterogeneity: An application to stock crash analysis

AbstractVarious random effects models have been developed for clustered binary data; however, traditional approaches to these models generally rely heavily on the specification of a continuous random effect distribution such as Gaussian or beta distribution. In this article, we introduce a new model that incorporates nonparametric unobserved random effects on unit interval (0,1) into logistic regression multiplicatively with fixed effects. This new multiplicative model setup facilitates prediction of our nonparametric random effects and corresponding model interpretations. A distinctive feature of our approach is that a closed‐form expression has been derived for the predictor of nonparametric random effects on unit interval (0,1) in terms of known covariates and responses. A quasi‐likelihood approach has been developed in the estimation of our model. Our results are robust against random effects distributions from very discrete binary to continuous beta distributions. We illustrate our method by analyzing recent large stock crash data in China. The performance of our method is also evaluated through simulation studies.

Does the S&P index effect differ between large and small company stocks?

PurposeThe purpose of this study is to compare market reactions to the change in the demand by index funds between large and small company stocks by examining the transition of the S&P 500, S&P 400 MidCap and S&P 600 SmallCap indexes from market capitalization to free-float weighting. This unique information-free event allows not only avoiding confounding information signaling and investor awareness effects but also comparing the effect of the decrease in demand on stocks of different sizes.Design/methodology/approachThis study uses the event study methodology to calculate abnormal returns and trading volume around the full-float adjustment day. It also tests for significant changes in institutional ownership and liquidity. Multivariate regressions are used to examine the relation of liquidity changes and price elasticity of demand to the cumulative abnormal returns around the full-float adjustment day.FindingsThis study finds significant decreases in stock price accompanied with significant increases in trading volume on the full-float adjustment day, and significant gains in quasi-indexer institutional ownership and liquidity. The main finding is that cumulative abnormal returns around the event period are related to changes in the number of quasi-indexer and transient institutional shareholders, not to changes in liquidity or price elasticity of demand.Originality/valueThis study provides the first comprehensive comparison analysis of stock market reactions to the decline in demand between large and small company stocks. As an important implication for future studies of the index effect, changes in institutional ownership should be considered in the analysis.

Remote estimation of soil organic carbon under different land use types in agroecosystems of Eastern China

Soil organic carbon (SOC) plays a key role in soil function, ecosystem services, and the global carbon cycle. Large SOC stocks accumulate in agroecosystems, but the estimates of SOC distribution and magnitude in agroecosystems still have large uncertainties in global products. Based on multiple high-resolution environmental variables (terrain derived from digital elevation model, climate and organism from Landsat 8 OLI) and 369 observed soil samples from 2019 to 2021, two machine learning methods, random forest (RF) and support vector machine (SVM) models, were used to estimate the content and spatial distribution of SOC in agroecosystems of Eastern China. We proposed a hybrid model in which the optimal predictors of SOC were selected for different land use types (cropland, planted forest and grassland), and it aimed to improve the performance of machine learning. Our results showed that (1) the hybrid models performed better than the global models, and the Random forest-Hybrid (RF-Hybrid) model led to the highest prediction accuracy, with a validation R2 of 0.65 and RMSE of 5.76 g kg−1. (2) The SOC content in the agroecosystems of Eastern China among different land use types ranked in the following order: planted forest (19.92 g kg−1) > cropland (17.51 g kg−1) > grassland (17.30 g kg−1). However, in North China, the SOC content in cropland (14.04 g kg−1) was much lower than that in planted forest (17.21 g kg−1) and grassland (17.07 g kg−1), which was caused by excessive mechanized operation. (3) The agroecosystem in Northeast China presented the highest mean SOC content (26.55 g kg−1) due to low temperature. (4) Our estimations (R2 = 0.53, RMSE = 6.74 g kg−1, 30-m resolution) were more detailed and precise than the existing global SOC maps (Soil Grids: R2 = 0.26, RMSE = 12.44 g kg−1, 250-m resolution; HWSD: R2 = 0.06, RMSE = 41.07 g kg−1, 1000-m resolution). The results may improve the accuracy of agroecosystem carbon mapping and contribute to SOC assessments in agricultural ecosystems.

The effect of oil price shocks on stock market performance in selected African countries

AbstractThe study's objective was to investigate how changes in oil prices affect stock market performance. The study's population consisted of selected African countries chosen based on factors like the size of their stock markets and whether or not they import or export oil. The world development indicator (WDI) and the OPEC bulletin or website served as sources for the data. The vector error correction model was used to analyse the collected data. Regarding the impact of oil price fluctuations on the performance of the stock market, the findings of the study were mixed. Oil price fluctuations have a positive impact on stock market performance for countries that import oil. For oil‐trading countries, the impacts were found to differ across examined countries. Oil price fluctuations had a mixed effect on both large and small stock markets. This demonstrates how crucial it is to investigate changes in the price of oil and how they might impact stock market performance, particularly in African countries.

Graphite, Sheelite and Cassiterite Mineralized Skarns of Frag Al Ma, Sidi Bou Othmane District, Jebilet, Morocco

Sidi Bou Othmane region in the Central Jebilet is formed by a Devonian schistose series. The polyphase Hercynian deformation in this area is characterised by penetrative, subvertical, synmetamorphic schistosity (S1), accompanied by folding. Syntectonic granitic intrusions, hidden in the Sidi Bou Othmane region, is marked by a contact of metamorphism, which responsible for the replacement phenomena observed essentially in the limestones of the region which are transformed into graphitic Sn-W exoskarns. Syn-tectonic, skarnification is polyphase : (i) prograde stage (T= 500- 750°C) : with graphite, garnets, idocrase, pyroxene, wollastonite, quartz, scheelite and molybdenite, crossed by a network of successive veins (garnet, idocrase, wollastonite, quartz and calcite; (ii) retrograde stage (T= 400-500°C): with garnet, idocrase, pyroxene wollastonite, quartz, calcite, epidote scheelite and cassiterite; (iii) hydrothermal alteration stage (T ≤400°C) : with sericite and clay accompanied by abundant scheelite and cassiterite, favoured by the high oxidation rate. Therefore, they would have formed in a reduced environment, in relation to large batholiths or stocks of quartz diorites and/or granites in syn, late- to post-orogenic to anorogenic contexts, in the absence of any cogenetic volcanism. The economic mineralisation of graphite was formed mainly during prograde stage, under reducing conditions. It was formed by devolatilization of a bituminous origin linked to the reef limestones and organic matter, trapped in the shales according to the following reaction:

Impact of Geopolitical Risks on the Stock Market : Evidence from Large, Mid, and Small-Cap Stocks

Impact of Geopolitical Risks on the Stock Market : Evidence from Large, Mid, and Small-Cap Stocks

„Das ging ja nur hier…“ – Wohneigentümerstrukturen und Segregation in ostdeutschen Großwohnsiedlungen

Throughout the last two decades, large housing estates in eastern Germany have become the scene of an increased concentration of low-income households. At the same time, considerable shifts in the structure of home ownership have been documented in these areas. National and international investors have acquired large housing stocks here and become a fundamental part of the local housing markets. This paper discusses the connection between both developments. Based on a case study in two large housing estates in Halle (Saale) and Schwerin, it is argued that the relative impoverishment of large housing estates can be traced back to two developments on the supply side: On the one hand, municipal housing companies are increasingly made responsible for the provision of homes for households that cannot provide for themselves on the market. Due to the uneven spatial distribution of municipal housing, this leads to an increased concentration of poor households in the large housing estates. On the other hand, letting policies of financial investors are characterised by tight yield requirements. In view of a rather restrained demand for the housing they manage, they therefore increasingly rent their flats to population groups that are avoided by other landlords. Together, these developments operate like a ‘segregation machine’, which continuously shifts low-income population groups to the large housing estates.

Director trades, profitability and market efficiency: New evidence

We investigate if directors of Australian companies can generate abnormal returns on their reported trades, if these abnormal returns are significant enough to be mimicked by outsiders, and if insider trades have an effect on returns of other investors. We find that insiders take advantage of their private information in stocks of larger corporations, but generally do not in medium and small capitalization firms, indicating that the insiders are attracted to the liquidity and a greater presence of uninformed traders in large stocks. We find that outsiders can make profitable trades net of transaction costs by following insiders’ sale trades in large and medium size firms, otherwise tracking insider trades result in net losses for outsiders. They accumulate on average a net abnormal profit of 4.17 % after a year following insiders sale trades. We propose that market quality can be improved with public access to good quality aggregated data on reported director insider trades.

Influence of soil properties and land use on organic carbon storage in agricultural soils near hedges

AbstractIn this context of climate change, agroforestry systems are acknowledged to have a good potential to increase carbon storage in agricultural areas. However, the carbon storage potential of agroforestry systems still needs to be quantified accurately, especially for hedges. The objectives of this study were to (1) add references to the existing literature on the potential for soil organic carbon (SOC) storage near hedges and (2) identify the main factors that influence the variability in this potential. To this end, we sampled soil in the adjacent fields of 25 hedges in France with mixed crop‐livestock agriculture, with sampling on both sides for 20 hedges and sampling on only one side for five hedges, giving a total of 45 study sites. We measured SOC stocks to a depth of 90 cm at distances of 1, 2, 3 and 10 m from the hedge. The results showed that hedges have a strong potential to store carbon in soils, with a mean increase of 15% in SOC stock within 3 m of the hedge. This increase in SOC stock had high variability because of site characteristics. Additional SOC stocks were the largest in rotations of annual crops and grasslands with a permanent grass strip 1 m wide near the hedge, followed by rotations of annual crops, permanent grasslands and rotations of annual crops and grasslands. Large additional SOC stocks because of the hedge were also associated with soils that had a high C:N ratio. The contribution of this type of land management to soil carbon storage thus depends on the local context in which it is implemented.

Seedling drought responses governed by root traits, site-soil moisture regimes and overstory competition-facilitation

Periodic drought may interact with spatially patterned soil moisture regimes, canopy disturbance and species seedling traits to influence tree regeneration processes in northern temperate forests. In northern Michigan, USA, we assessed the effects of regional upland soil moisture regimes (six sites classified from dry to mesic) and tree canopy shading (% light) on planted-seedling dry mass, probability of mortality and functional traits for eight tree species varying in shade tolerance and natural distribution over soil moisture gradients (i.e., drought tolerance): Quercus velutina, Quercus alba, Quercus rubra, Prunus serotina, Acer rubrum, Acer saccharum, Fraxinus americana, and Betula alleghaniensis. The assessment period included droughts during the seedlings’ 2nd and 3rd growing seasons. High mortality (especially on drier-classified sites and in more open, high-light environments) and negative associations of soil water minima with mortality collectively suggest drought-driven mortality across sites. In contrast, canopy shade driven mortality occurred only on mesic sites at <10 % light. Overstory canopies facilitated seedling survival relative to more open environments, with survival maxima ranging from 3 to 20 % light among sites. Among species, probability of survival was 1) highest for Quercus species (∼0.70) and lowest for B. alleghaniensis (0.10), 2) positively and generally associated with drought tolerance, but not associated with shade tolerance, and 3) positively and strongly associated with species seed-size related differences in total dry mass, root dry mass and rooting depth. In turn, rooting depth (range 3–68 cm) was positively related to seedling water status, and water status to survival during drought. In summary, site soil moisture regimes, facilitation vs. competition via variation in canopy density, and size-related species traits drove patterns of young seedling mortality during an interval that included droughts. Results suggests current drought regimes likely have strong influence on canopy composition across the region’s spatially patterned dry to mesic soil gradients, and may have larger impacts if drought intensifies with climate change. Our results can aid development of planting strategies for assisted migration and other emerging needs, including planting 1) species more drought adapted than those dominating current overstories, 2) large stock with well-developed root systems, and 3) in microsites that maximize canopy facilitation.

La evolución y el destino del ahorro extraordinario acumulado por los hogares españoles desde el inicio de la pandemia

Rationale Households overall built up a large stock of excess savings during the pandemic. The use of these excess savings and the potential amount currently available for spending are relevant to understanding how they may support consumption over the coming quarters. Takeaways •To end-2022, households had barely used the excess savings accumulated during the pandemic for purchases of consumer goods and services. The bulk of these funds have been channelled towards financial investments, specifically deposits and investment funds. •A more modest proportion of these savings – albeit one that has been increasing since 2021 – has been used to purchase non-financial assets (in particular, property) and to repay home loans. •A large share of the excess savings accumulated during the health crisis is concentrated among higher-income households, to such an extent that households in the bottom income quintile barely increased their savings in this period.

ANALYSIS OF THE IMPACT OF THE SITUATION IN THE WORLD ON «FORTEBANK» JSC

In an effort to curb the spread of the virus around the world, something hitherto unheard of has been attempted – shutting down economies in different regions, in some cases twice, leaving tens of millions of people out of work and millions of businesses shut down. These people and companies are customers of banks, and as a result of their inability to meet their obligations to banks, the number of defaults may increase dramatically.Unlike many past shocks, the COVID-19 crisis is not just a banking crisis, but a real economy crisis. Banks will undoubtedly suffer as credit losses cascade through the economy and demand for banking services falls. But the reasons for the problems are not in the banks. The global banking system entered the crisis with a good capitalization and much more stable than it was 12 years ago.The good news is that the banking sector is sufficiently capitalized to withstand the coming shock.In 2020, the financial sector of Kazakhstan developed under the influence of a double shock: oil prices fell and, as expected, as a result of the restrictive measures imposed in connection with the coronavirus pandemic, business activity decreased.This year is projected to be the most significant drop in economic growth in the last 20 years. According to the forecasts of the Ministry of National Economy of the Republic of Kazakhstan, the decline in GDP for the year will be - 2.1%, and according to the IMF – at the level of - 2.7%. It is obvious that the determining factor in the development trajectory of the country's financial sector this year and next is the scenario of the spread and the possibility of overcoming the pandemic, its impact on business activity and market relations.The banking sector approached the beginning of the pandemic with a large capital stock, as evidenced by the independent asset quality assessment (AQR) for the 14 largest banks, which account for 87% of the banking system's assets.In the group-14 highly qualified large banks are included in JSC" ForteBank". The main financial indicators of banks during the pandemic period did not decrease, income received from ATMs, as well as Rosli.

Energy consumption prospective scenarios application on a land use mix - A case study of the Wallonia building stock in Belgium

Cities are looking for sustainable ways to manage energy consumption in buildings. Many researchers have been focusing on assessing buildings' energy consumption without considering building categorization. In this study, Entropy and Herfindahl-Hirschman indices are used to create 12 land use mix (LUM) classes at the statistical sector (SS) scale for the Wallonia building stock, including nearly 1.7 million buildings. The categorization of the building stock into classes increases accuracy when applying forecast scenarios to choose the best energy strategies. The innovation consists in applying the concept of LUM to analyze the energy consumption of a large regional building stock and to compare the defined LUM classes with residential built density classes.Demography, degree days, heavy and light renovations, photovoltaic panels (PVs) and 3 mixed scenarios are applied to the created 12 LUM classes to forecast their energy evolution until 2050. Industrial buildings are playing an important role in PVs installation where energy reduction is the highest in the 7th LUM class (medium mix industrial with residential only) with -14.27%. Combining five scenarios results in -35%, -56% and -60% decrease in energy consumption in the 11th LUM class (high mix residential) for mixed scenarios 1, 2 and 3 respectively.

Retail Derivatives and Sentiment: A Sentiment Measure Constructed from Issuances of Retail Structured Equity Products

ABSTRACTWe use retail structured equity product (SEP) issuances to construct a new sentiment measure for large capitalization stocks. The SEP sentiment measure predicts negative abnormal returns on the SEP reference stocks based on a variety of factor models, and also predicts returns in Fama‐MacBeth regressions that include a wide range of covariates. Consistent with our interpretation that SEP issuances reflect investor sentiment, aggregate SEP issuances are highly correlated with the Baker‐Wurgler sentiment index. Tobit regressions reveal that proxies for attention and sentiment predict SEP issuance volumes, providing additional evidence consistent with the hypothesis that SEP issuances reflect sentiment.

Liquidity, Volume, and Order Imbalance Volatility

ABSTRACTWe examine the dynamics of liquidity using a comprehensive sample of U.S. stocks in the post‐decimalization period. Motivated by a continuous‐time inventory model, we compute a high‐frequency measure of order imbalance volatility to proxy for the inventory risk faced by liquidity providers. We show that high‐frequency order imbalance volatility is an important driver of liquidity and explains the often positive time‐series relation between spread and volume for large stocks, which seems to run counter to most theoretical models. Furthermore, order imbalance volatility is priced in the cross‐section of stock returns.

Exposed sediments in a temperate-climate reservoir under dam decommissioning contain large stocks of highly bioreactive organic matter

Dam decommissioning (DD) is used to solve economic and social problems posed by old dams. However, we ignore the effect of DD on the content and reactivity of large stocks of organic matter (OM) buried in reservoir sediments. We explored temporal changes in the content and reactivity of sediment OM during the first 580 days after the drawdown phase of DD of a large reservoir in the N Iberian Peninsula. We determined the content of sediment OM as organic carbon (OC) in bulk sediment OM and water-extractable OM (WEOM). We estimated the reactivity of bulk sediment OM as its respiration rate and carbon-to-nitrogen ratio, and that of sediment WEOM as its respiration rate, percent biodegradable dissolved OC (%BDOC), and SUVA254. The content of bulk sediment OM was 84 ± 5.1 (mean ± SE) mg OC/ g dry sediment, comparable to the values in the literature on sediment OM in dry sediments from lentic, but higher than in lotic ecosystems. The content of sediment WEOM was 0.81 ± 0.05 mg DOC/g dry sediment, higher than the values in the literature on sediment WEOM from lakes, soils, and rivers. On average, 41 % of WEOM was consumed by microorganisms in two days of incubation, showing the great reactivity of this OM fraction. The content of bulk sediment OM and the respiration rate of WEOM showed a nonlinear temporal trend, while %BDOC increased linearly with sediment exposure time. The labile OM produced by the vegetation that rapidly recolonized the reservoir and photoreactions may explain the temporal increase in %BDOC. Our results suggest that exposed sediments can be a source of labile OM and high C emissions in the river reach downstream of the reservoir after DD.

Patterns of pharmaceutical supplies and medicines donations received during a natural disaster

BackgroundIn response to emergencies, such as wildfires, donations of pharmaceuticals often occur. These donations can be given directly by governments, to non-governmental organizations as corporate donations, or by private entities that donate to individual health institutions. ObjectiveThis paper aimed to collect, review and analyze pharmaceutical product donations received during the natural disaster caused by wildfires in the San Luis province, Argentina, in September and October 2020. MethodsA descriptive, cross-sectional, and retrospective study was performed. An introductory approach to good donation practices was also carried out. Medicines were classified and in the case of products that were not suitable for administration, these were discarded. ResultsA total of 15,593 units were segregated, of which 52.8% were over-the-counter products and 47.2% were prescription drugs. 86.3% (13,467 units) were accepted, while 13.7% (2126 units) had to be destroyed. The value of donations totaled USD 16,544. The analysis of the results showed that an important part of the donations was irrelevant in the emergency context. Donations were also received in incorrect amounts, which generated a large stock of medicines that couldn’t be used. In emergencies, inappropriate donations create additional work during sorting, storage, and distribution, increasing the time professionals need to complete tasks. This extra work can easily overwhelm limited human and logistical resources. ConclusionsIt is important to previously evaluate the real need for donations. In addition, the distribution of donations must be done through pre-established systems and policies. Otherwise, unsolicited and unnecessary drug donations become wasteful and should therefore be avoided.

Carbon density in boreal forests responds non-linearly to temperature: An example from the Greater Khingan Mountains, northeast China

Boreal forests play a crucial role in the global carbon (C) cycle and in climate stabilization. To better predict global C budgets, it is important to accurately estimate the size of forest C pools, and to identify the factors affecting them. We used national forest inventory data for the Greater Khingan Mountains, northeast China from 1999 to 2018 and 149 additional field plots to estimate C storage and its changes in forest vegetation, excluding C stored in soils, and to calculate the total C density in forest ecosystems. From 1999 to 2018, the vegetation C storage and density increased by 92.22 Tg and 4.30 Mg C ha−1, respectively, while the mean C sink was 4.61 Tg C yr−1. Carbon storage and density showed the same pattern, with the largest stocks in trees, followed by herbs, shrubs, and then litter. Mean C density was higher in mature forests than in young forests. The maximum C density was recorded in Populus davidiana forests, and was 2.2-times larger than in Betula davurica forests (the minimum). The mean (± standard error) total C density of forest ecosystems was 111.3 ± 2.9 Mg C ha−1, including C stored in soils. Mean annual temperature (MAT) controlled total C density, as MAT had positive effects when it was lower than the temperature of the inflection point (-2.1 to -4.6 °C) and negative effects when it was above the inflection point. The rate of change in the total C density depended on the quantile points of the conditional distribution of total C density. Natural and anthropogenic disturbances had weaker effects on C density than temperature and precipitation. In conclusion, our results indicate that there might be a temperature-induced pervasive decrease in C storage and an increase in tree mortality across Eastern Asian boreal forests with future climate warming.

Estimating stocking weights for Atlantic salmon to grow to market size at novel aquaculture sites with extreme temperatures

Land-based hatcheries are now capable of growing large Atlantic salmon (Salmo salar) post-smolts (approximately 150 – 1000 g), which means that marine net-pens can be stocked with substantially larger fish compared to traditional stocking sizes (&amp;lt; 150 g). This stocking strategy typically aims to reduce the time required for fish to grow to market size in the marine environment and limit risks (e.g., exposure to pathogens and diseases, opportunities for escapes). This study investigates another potential application of this strategy: the use of novel sites in areas previously considered unsuitable for aquaculture due to seasonally cold temperatures. The thermal-unit growth coefficient (TGC) model was applied to estimate the stocking weight needed to reach a harvest size of 5.5 kg, based on observed degree days for three sites. High resolution, depth-partitioned temperature time series from coastal locations in Atlantic Canada were used to represent a short, medium, and long growing season, as constrained by seasonal temperature extremes. Growing days for model inputs were defined as temperatures &amp;gt; 4 °C and trending up for stocking, &amp;lt; 18 °C to account for heat stress, and &amp;gt; -0.7 °C to avoid superchill conditions. Different TGC values were applied to simulate remedial, average, and elite growth performance. There was a range of model stocking weight estimates for each site (1.5 – 2.5 kg, 0.94 – 2.8 kg, and &amp;lt; 0.1 – 0.52 kg, for the short, medium, and long season sites, respectively). Results were sensitive to the number of degree days, heat stress threshold, and TGC value. At the two sites where season length was constrained by superchill, fish with a stocking weight of approximately 1.5 kg could grow to market size in shallow water depths (&amp;lt; 15 m), assuming elite growth performance. This investigation suggests that with appropriate growth performance assumptions and high-resolution temperature data, large post-smolt stocking strategies could enable the use of novel sites in coastal areas previously considered unsuitable for aquaculture.

Isotope and trace element compositions of silver-bearing ores in the Balkans as possible metal sources in antiquity

Ore deposits in the Balkan Peninsula were intensively mined for silver and other metals in the Roman and medieval periods. Coinage mainly issued by tribal groups between the early 5th and the end of the 3rd century BCE provides indirect evidence that silver extraction predates the Roman conquest of the region. However, identification of centers of past metal production and reconstruction of large-scale silver fluxes can only be achieved using a comprehensive geochemical database of potential ores. Here, we present high-precision Pb–Ag–S isotope data and trace element systematics for 128 ore samples from 36 mineralizations from the Balkans as well as one semi-reacted ore from a settlement site (=archaeological sample) and one andesite analyzed as a whole-rock and as a K-feldspar separate. Each ore site was selected for its geological characteristics and documented or assumed historical and/or archaeological significance.The reported data reconstruct the formation of ore bodies from large pre-existing Pb stocks derived from upper crustal sources, modified by tectonic and metasomatic processes, and eventually remobilized by magmatic activity. Lead isotope maps establish distinct isotopic domains which are linked to geological characteristics and enable an enhanced assessment of potential metal sources in provenance studies. Silver isotopes underscore the importance of hypogene ores of hydrothermal origin comprising galena or sulfosalt minerals as the main silver carrier phases and they can circumscribe ore deposits to those actually used as bullion sources of ancient coinage. We show that the Ag isotope signatures and the silver content of the argentiferous galena-rich ores in the Kopaonik and Zletovo districts (Serbia, Kosovo, and North Macedonia), combined with field evidence for historical metal production and geographical considerations, make them the most likely sources of silver which could have been used for coinage issued by mints in the interior of the Balkans.