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2022 ◽  
Author(s):  
Ann Caroline Danielsen ◽  
Marion MN Boulicault ◽  
Annika Gompers ◽  
Tamara Rushovich ◽  
Katharine MN Lee ◽  
...  

In order to characterize how sex disparities in COVID-19 mortality evolved over time in New York State (NY), we analyzed sex-disaggregated data from the US Gender/Sex COVID-19 Data Tracker from March 14, 2020 to August 28, 2021. We defined six different time periods and calculated mortality rates by sex and mortality rate ratios, both cumulatively and for each time period separately. As of August 28, 2021, 19 227 (44.2%) women and 24 295 (55.8%) men died from COVID-19 in NY. 72.7% of the cumulative difference in the number of COVID-19 deaths between women and men was accrued between March 14 and May 4, 2020. During this period, the COVID-19 mortality rate ratio for men compared to women was 1.56 (95% CI: 1.52-1.61). In the five subsequent time periods, the corresponding ratio ranged between 1.08 (0.98-1.18) and 1.24 (1.15-1.34). While the cumulative mortality rate ratio of men compared to women was 1.34 (1.31-1.37), the ratio equals 1.19 (1.16-1.22) if deaths during the initial COVID-19 surge are excluded from the analysis. This article shows that in NY the magnitude of sex disparities in COVID-19 mortality was not stable across time. While the initial surge in COVID-19 mortality was characterized by stark sex disparities, these were greatly attenuated after the introduction of public health controls.


2021 ◽  
Author(s):  
Can Küçükgül ◽  
Özalp Özer ◽  
Shouqiang Wang

Many online platforms offer time-locked sales campaigns, whereby products are sold at fixed prices for prespecified lengths of time. Platforms often display some information about previous customers’ purchase decisions during campaigns. Using a dynamic Bayesian persuasion framework, we study how a revenue-maximizing platform should optimize its information policy for such a setting. We reformulate the platform’s problem equivalently by reducing the dimensionality of its message space and proprietary history. Specifically, three messages suffice: a neutral recommendation that induces a customer to make her purchase decision according to her private signal about the product and a positive (respectively (resp.), negative) recommendation that induces her to purchase (resp., not purchase) by ignoring her signal. The platform’s proprietary history can be represented by the net purchase position, a single-dimensional summary statistic that computes the cumulative difference between purchases and nonpurchases made by customers having received the neutral recommendation. Subsequently, we establish structural properties of the optimal policy and uncover the platform’s fundamental trade-off: long-term information (and revenue) generation versus short-term revenue extraction. Further, we propose and optimize over a class of heuristic policies. The optimal heuristic policy provides only neutral recommendations up to a cutoff customer and provides only positive or negative recommendations afterward, with the recommendation being positive if and only if the net purchase position after the cutoff customer exceeds a threshold. This policy is easy to implement and numerically shown to perform well. Finally, we demonstrate the generality of our methodology and the robustness of our findings by relaxing some informational assumptions. This paper was accepted by Gabriel Weintraub, revenue management and market analytics.


Author(s):  
Chukwuemeka Patrick Ogbu ◽  
Raphael Ehigiator-Irughe

Engineering, procurement and Construction (EPC) projects in the oil and gas sector of Nigeria are under-researched. This leaves investors with little or no guide on the cost-overrun risks of oil and gas depot projects. Using the qualitative case study research technique, this study investigated cost overrun in the civil works of a petroleum products depot project in Lagos, Nigeria. The objectives were to ascertain the reasons for cost overrun and the areas of substantial cost overrun in the project. It was found that except for the cost of construction of “gantry” which was under-measured as a result of use of a wrong method of costing, the rest of the major facilities experienced cost overrun with a cumulative difference of 106%. It was also discovered that the cost overruns mainly originated from design and construction activities. The study recommends the timely engagement of consultants to review the conceptual designs of contractors and monitor the activities of EPC contractors for oil and gas depot projects on behalf of clients. Such consultants should not, however, have powers to control the contractors. As much as possible, parties to EPC contracts should use standard conditions of contract that will better reflect their intentions rather than contrive bespoke conditions.


Author(s):  
Ignatius Ngala Kiming ◽  
Eric Kongnso Moye ◽  
Jude Kwei

This study aims at analyzing the effects of climate variability on bee farming in Mount Oku. The guiding premise is that climate variability has brought about environmental changes causing a fall in the quantity and quality of honey. A mixed research approach was adopted in collecting data. Questionnaires were administered to 90 purposively selected bee farmers and interviews conducted with key actors in honey production. SPSS, version 20.0 was used to analyze data while the cumulative difference index helped establish climatic anomalies and trends. Findings revealed falling rainfall trends with marked seasonal variations. Temperatures show a rising trend with little but sensitive anomalies. This has affected periods of flowering for bee plants as acknowledged by 97% of bee farmers. Hive colonization rate has been decreasing (74% - 55%), with an increasing rate of abscond (34% -46%), resulting in a reduction in honey yields. Climate variability has increased the magnitude of other environmental stressors such as bush fires and forest degradation, while reducing the growing period of some bee plants. The coping strategies put in place by bee farmers are limited and policies need to address this situation so as to maintain the quality of OKU honey.


2020 ◽  
Author(s):  
Chandrakant Singh ◽  
Ruud J. van der Ent ◽  
Ingo Fetzer ◽  
Lan Wang-Erlandsson

<p>Change in rainfall patterns and extended drought events can cause water stress in the rainforest which can also lead to a permanent shift of the biome into a savanna state. Rainforest in response may adapt to such environmental stress conditions to sustain ecosystem functioning or reduce functioning altogether. Previous studies related to forest resilience have mostly relied on precipitation or climatological drought as a control variable, but neither is a direct measure of forest resilience. As such, forest adaptability dynamics of the forest is poorly understood. Our research defines this adaptation capacity of vegetation as a dynamic reserve which rainforest can utilize before a potential shift to an alternate stable state, as the resilience of the rainforest. Here, we introduce the Rootzone Storage Potential (RZSP) as a direct water stress metric to understand adaptive forest resilience behaviour, using the cumulative difference between precipitation and potential evaporation (radiation-based). Since the potential evaporation used for RZSP calculation is purely radiation-based, it minimizes the effect of moisture recycling (and transport) on the system. RZSP is the potential of vegetation to optimize their resources enduring the greatest dry period. In this study, we have investigated the spatio-temporal resilience loss of the South American and African rainforest. An increasing trend of resilience loss was observed in the past few decades. Using RZSP is a useful indicator for estimating resilience dynamics and water stress characteristics of the rainforest. </p>


2019 ◽  
Vol 10 (2) ◽  
pp. 149-155
Author(s):  
Cindy Zhao ◽  
Kathleen Lee ◽  
David Do

ObjectiveTo use the variations in neurology consultations requested by emergency department (ED) physicians to identify opportunities to implement multidisciplinary interventions in an effort to reduce ED overcrowding.MethodsWe retrospectively analyzed ED visits across 3 urban hospitals to determine the top 10 most common chief complaints leading to neurology consultation. For each complaint, we evaluated the likelihood of consultation, admission rate, admitting services, and provider-to-provider variability of consultation.ResultsOf 145,331 ED encounters analyzed, 3,087 (2.2%) involved a neurology consult, most commonly with chief complaints of acute-onset neurologic deficit, subacute neurologic deficit, or altered mental status. ED providers varied most in their consultation for acute-onset neurologic deficit, dizziness, and headache. Neurology consultation was associated with a 2.3-hour-longer length of stay (LOS) (95% CI: 1.6–3.1). Headache in particular has an average of 6.7-hour-longer ED LOS associated with consultation, followed by weakness or extremity weakness (4.4 hours) and numbness (4.1 hours). The largest estimated cumulative difference (number of patients with the specific consultation multiplied by estimated difference in LOS) belongs to headache, altered mental status, and seizures.ConclusionA systematic approach to identify variability in neurology consultation utilization and its effect on ED LOS helps pinpoint the conditions most likely to benefit from protocolized pathways.


2018 ◽  
Vol 14 (3) ◽  
pp. 221-229 ◽  
Author(s):  
Gianfrancesco Fiorini ◽  
Cesare Cerri ◽  
Antonello E. Rigamonti ◽  
Silvia Bini ◽  
Nicoletta Marazzi ◽  
...  

Purpose The purpose of this paper is to evaluate gender-related differences in the use of drugs for chronic diseases in undocumented migrants. Design/methodology/approach The authors analyzed the databases of two charitable organizations providing medical help and medicines to undocumented migrants. Data were available for 9,822 patients in the period 2014–2016. The authors grouped medicines according to the Anatomical Therapeutic Chemical (ATC) classification. We considered the ATC group as an indicator of a group of diseases. Findings Both males and females needed medicines for chronic diseases in a comparable manner. When we analyzed the age distribution, The authors noticed that males showed a tendency to begin to be affected at an earlier age; however, this cumulative difference was not statistically significant. But when we looked at six groups of drugs separately (cardiovascular, respiratory, anti-thrombotic, neurologic, psychiatric, anti-diabetic), the authors found that females always needed drugs for chronic diseases at a later age, always with a significant difference (p<0.0001 for cardiovascular, antithrombotic, antidiabetic and psychoactive drugs; p<0.002 for neurologic products; p<0.04 for drugs used in chronic respiratory conditions). Research limitations/implications This is a retrospective study based on the analysis of existing databases, but the peculiar features of this population (undocumented migrants) do not allow at the moment controlled studies. Practical implications Our observations could be important when planning public health strategies, especially in the field of prevention. Originality/value This is the first report of gender differences in the use of medicines for chronic diseases within a large sample of undocumented migrants.


2016 ◽  
Vol 28 (4) ◽  
pp. 589-603 ◽  
Author(s):  
Hannah Tickle ◽  
Maarten Speekenbrink ◽  
Konstantinos Tsetsos ◽  
Elizabeth Michael ◽  
Christopher Summerfield

Humans are often observed to make optimal sensorimotor decisions but to be poor judges of situations involving explicit estimation of magnitudes or numerical quantities. For example, when drawing conclusions from data, humans tend to neglect the size of the sample from which it was collected. Here, we asked whether this sample size neglect is a general property of human decisions and investigated its neural implementation. Participants viewed eight discrete visual arrays (samples) depicting variable numbers of blue and pink balls. They then judged whether the samples were being drawn from an urn in which blue or pink predominated. A participant who neglects the sample size will integrate the ratio of balls on each array, giving equal weight to each sample. However, we found that human behavior resembled that of an optimal observer, giving more credence to larger sample sizes. Recording scalp EEG signals while participants performed the task allowed us to assess the decision information that was computed during integration. We found that neural signals over the posterior cortex after each sample correlated first with the sample size and then with the difference in the number of balls in either category. Moreover, lateralized beta-band activity over motor cortex was predicted by the cumulative difference in number of balls in each category. Together, these findings suggest that humans achieve statistically near-optimal decisions by adding up the difference in evidence on each sample, and imply that sample size neglect may not be a general feature of human decision-making.


2011 ◽  
Vol 5 (1) ◽  
pp. 107-124 ◽  
Author(s):  
A. Fischer

Abstract. The geodetic mass balances of six Austrian glaciers over 19 periods between 1953 and 2006 are compared to the direct mass balances over the same periods. For two glaciers, Hintereisferner and Kesselwandferner, case studies showing possible reasons for discrepancies between the geodetic and the direct mass balance are presented. The mean annual geodetic mass balance for all periods is −0.5 m w.e. a−1, the mean annual direct mass balance −0.4 m w.e. a−1. The mean cumulative difference is −0.6 m w.e., the minimum −7.3 m w.e., and the maximum 5.6 m w.e. The accuracy of geodetic mass balance may depend on the accuracy of the DEMs, which ranges from 2 m w.e. for photogrammetric data to 0.02 m w.e. for airborne laser scanning (LiDAR) data. Basal melt, seasonal snow cover, and density changes of the surface layer also contribute up to 0.7 m w.e. to the difference between the two methods over the investigated period of 10 yr. On Hintereisferner, the fraction of area covered by snow or firn has been changing within 1953–2006. The accumulation area is not identical with the firn area, and both are not coincident with areas of volume gain. Longer periods between the acquisition of the DEMs do not necessarily result in a higher accuracy of the geodetic mass balance. Trends in the difference between the direct and the geodetic data vary from glacier to glacier and can differ systematically for specific glaciers under specific types of climate forcing. Ultimately, geodetic and direct mass balance data are complementary, and great care must be taken when attempting to combine them.


Author(s):  
James R. McCusker ◽  
Kourosh Danai ◽  
David O. Kazmer

Model validation is the procedure whereby the fidelity of a model is evaluated. The traditional approaches to dynamic model validation consider model outputs and observations as time series and use their similarity to assess the closeness of the model to the process. A common measure of similarity between the two time series is the cumulative magnitude of their difference, as represented by the sum of squared (or absolute) prediction error. Another important measure is the similarity of shape of the time series, but that is not readily quantifiable and is often assessed by visual inspection. This paper proposes the continuous wavelet transform as the framework for characterizing the shape attributes of time series in the time-scale domain. The feature that enables this characterization is the multiscale differential capacity of continuous wavelet transforms. According to this feature, the surfaces obtained by certain wavelet transforms represent the derivatives of the time series and, hence, can be used to quantify shape attributes, such as the slopes and slope changes of the time series at different times and scales (frequencies). Three different measures are considered in this paper to quantify these shape attributes: (i) the Euclidean distance between the wavelet coefficients of the time series pairs to denote the cumulative difference between the wavelet coefficients, (ii) the weighted Euclidean distance to discount the difference of the wavelet coefficients that do not coincide in the time-scale plane, and (iii) the cumulative difference between the markedly different wavelet coefficients of the two time series to focus the measure on the pronounced shape attributes of the time series pairs. The effectiveness of these measures is evaluated first in a model validation scenario where the true form of the process is known. The proposed measures are then implemented in validation of two models of injection molding to evaluate the conformity of shapes of the models’ pressure estimates with the shapes of pressure measurements from various locations of the mold.


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