Modeling Salt Usage During Snowstorms

2017 ◽  
Vol 2643 (1) ◽  
pp. 54-64
Author(s):  
Kun Xie ◽  
Kaan Ozbay ◽  
Yuan Zhu ◽  
Sami Demiroluk ◽  
Hong Yang ◽  
...  
Keyword(s):  
Inventory Management ◽  
Fixed Effects ◽  
Linear Models ◽  
Winter Season ◽  
Predictive Performance ◽  
The United States ◽  
Hierarchical Linear Models ◽  
Storm Duration ◽  
Storm Characteristics ◽  
The Impact

Snow can cause dangerous driving conditions by reducing pavement friction and covering road surface markings. Salt is widely used by highway maintenance managers in the United States to reduce the impact of snow or ice on traffic. For the development of long-term plans, especially for the next winter season, it is essential to know what factors affect salt usage and to determine the sufficient amount of salt needed in each depot location. This determination can be accomplished by estimating statistically robust models for salt usage prediction. In this study, historical data regarding storm characteristics and salt usage on the New Jersey Turnpike and Garden State Parkway were used to estimate those models. Linear models, hierarchical linear models, and hierarchical linear models with varying dispersion (HLVDs) were developed to predict the salt usage on the two highways. Results show that districts with higher average snow depth, longer storm duration, and lower average temperature were associated with greater salt usage. HLVD models were found to have the best predictive performance by including random parameters to account for unobserved spatial heterogeneity and by including fixed effects in the dispersion term. In addition, with the estimation of case-specific dispersion on the basis of storm characteristics, HLVD models could be used appropriately to estimate the upper bounds of salt usage, bounds that are not extremely large and could satisfy the salt demand in most cases. The findings of this study can provide highway authorities with valuable insights into the use of statistical models for more efficient inventory management of salt and other maintenance materials.

Does the second wave of COVID-19 undermine corporate immunity? International evidence

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Huy Viet Hoang ◽  
Cuong Nguyen ◽  
Khanh Hoang
Keyword(s):  
Stock Returns ◽  
Stock Price ◽  
Fixed Effects ◽  
Management Strategies ◽  
The United States ◽  
Least Square ◽  
Content Type ◽  
The Impact ◽  
Second Wave ◽  
Practical Implications

PurposeThis study compares the impact of the COVID-19 pandemic on stock returns in the first two waves of infection across selected markets, given built-in corporate immunity before the global outbreak.Design/methodology/approachThe data are collected from listed firms in five markets that have experienced the second wave of COVID-19 contagion, namely the United States (US), Australia, China, Hong Kong and South Korea. The period of investigation in this study ranges from January 24 to August 28, 2020 to cover the first two COVID-19 waves in selected markets. The study estimates the research model by employing the ordinary least square method with fixed effects to control for the heterogeneity that may confound the empirical outcomes.FindingsThe analysis reveals that firms with larger size and more cash reserves before the COVID-19 outbreak have better stock performance under the first wave; however, these advantages impede stock resilience during the second wave. Corporate governance practices significantly influence stock returns only in the first wave as their effects fade when the second wave emerges. The results also suggest that in economies with greater power distance, although stock price depreciation was milder in the first wave, it is more intense when new cases again surge after the first wave was contained.Practical implicationsThis paper provides practical implications for corporate managers, policymakers and governments concerning crisis management strategies for COVID-19 and future pandemics.Originality/valueThis study is the first to evaluate built-in corporate immunity before the COVID-19 shock under successive contagious waves. Besides, this study accentuates the importance of cultural understanding in weathering the ongoing pandemic across different markets.

241 Skeletal Muscle Mitochondrial Capacities Are Impacted by Breed and Temperament in Young Angus and Brahman Steers

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 127-127
Author(s):  
Chloey P Guy ◽  
Lauren T Wesolowski ◽  
Audrey L Earnhardt ◽  
Dustin Law ◽  
Don A Neuendorff ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Fixed Effects ◽  
Linear Models ◽  
Citrate Synthase ◽  
Volume Density ◽  
Skeletal Muscle Mitochondria ◽  
Mitochondrial Volume ◽  
Mitochondrial Volume Density ◽  
Brahman Steers ◽  
The Impact

Abstract Temperament impacts skeletal muscle mitochondria in Brahman heifers, but this has not been investigated in steers or between cattle breeds. We hypothesized mitochondrial measures would be greater in Angus than Brahman, temperamental than calm steers, and the trapezius (TRAP) than the longissimus thoracis (LT) muscle. Samples from calm (n = 13 per breed), intermediate (n = 12 per breed), and temperamental (n=13 per breed) Angus and Brahman steers (mean±SD 10.0±0.8 mo) were evaluated for mitochondrial enzyme activities via colorimetry. Calm and temperamental LT samples were evaluated for oxidative phosphorylation (P) and electron transfer (E) capacities by high-resolution respirometry. Data were analyzed using linear models with fixed effects of breed, muscle, temperament, and all interactions. Brahman tended to have greater mitochondrial volume density (citrate synthase activity; CS) than Angus (P = 0.08), while intrinsic (relative to CS) mitochondrial function (cytochrome c oxidase activity) was greater in Angus than Brahman (P = 0.001) and greater in TRAP than LT (P = 0.008). Angus exhibited greater integrative (per mg tissue) and intrinsic P with complex I (PCI), P with complexes I+II (PCI+II), maximum noncoupled E, and E with complex II (ECII; P ≤ 0.04) and tended to have greater intrinsic leak (P = 0.1) than Brahman. Contribution of PCI to total E was greater in Angus than Brahman (P = 0.01), while contribution of ECII to total E was greater in Brahman than Angus (P = 0.05). A trend for the interaction of breed and temperament (P = 0.07) indicated calm Angus had the greatest intrinsic ECII (P ≤ 0.03) while intrinsic ECII was similar between temperamental Angus and calm and temperamental Brahman. Integrative PCI+II and ECII, and the contribution of PCI and PCI+II to overall E tended to be greater in temperamental than calm steers (P ≤ 0.09), while intrinsic ECII tended to be greater in calm than temperamental steers (P = 0.07). The impact of these mitochondrial differences on meat quality measures remains to be determined.

Essays in Labour Economics: Evidence from Voluntary and Mandatory Wage Floors in the United States and New Zealand

2021 ◽  
Author(s):  
◽  
Jaime Lancaster
Keyword(s):  
New Mexico ◽  
New Zealand ◽  
Minimum Wage ◽  
Low Income ◽  
Fixed Effects ◽  
Local Minimum ◽  
The United States ◽  
Living Wage ◽  
Earnings Growth ◽  
The Impact

<p>This thesis expands the literature on minimum and living wages by investigating local minimum wage ordinances and voluntary living wage programs. This thesis is presented as three distinct papers; the first explores a county-wide minimum wage ordinance in New Mexico, USA, while papers 2 and 3 explore New Zealand’s voluntary living wage program. In the United States, local minimum wage ordinances are growing in popularity, and research is emerging on their effects. Setting minimum wages at the local level is politically easier than enacting Federal legislation, and local minimum wages may be better targeted to local economic conditions. In my first chapter, “Local Minimum Wage Laws and Labour Market Outcomes: Evidence from New Mexico,” I use fixed effects and synthetic control analysis to uncover the effects of a local minimum wage law on the Albuquerque/Bernalillo region of New Mexico, with a focus on how provisions exempting tipped workers affect gains in earnings. My findings reveal that these provisions can lead to reductions in hourly wages for workers exempted from the minimum wage even when the labour market is not harmed overall. I find that the minimum wage ordinance did not reduce teen employment but that it served to increase the supply of teen labour leading to an increase in the teen unemployment rate.  The second and third papers in this thesis address the voluntary living wage program in New Zealand. In the first quantitative work on New Zealand’s living wage, I utilize data from Statistics New Zealand’s Integrated Data Infrastructure (IDI) to explore several facets of the living wage experience for employers and employees. In the second paper, “The New Zealand Living Wage: Earnings, Labour Costs and Turnover,” I investigate the characteristics of New Zealand living wage firms and use fixed effects to examine the impact of living wage certification on employment, worker earnings and turnover. My results provide some evidence for increases in labour costs and worker earnings following certification but find that this change is driven by changes in small firms that employ few workers. I find no evidence of a reduction in turnover.  In my final chapter, “Who Benefits from Living Wage Certification?” I investigate the distribution of benefits from the living wage based on an employees’ pre-treatment earnings, time of hire and whether or not they remained employed with the living wage firm. To do this, I utilize a worker-level panel dataset containing the full earnings history of all workers that were employed for a living wage or matched control firm between January 2014 and December 2015. I use fixed effects models containing fixed effects for worker, firm and month to compare patterns of earnings growth for workers hired before certification (‘pre-hires’) with those hired after certification (‘joiners’) and those who left their living wage job but remained in the workforce (‘leavers’). I also estimate the impact of living wage employment on the earnings of low-income workers. I find that the financial benefit of the living wage accrues almost exclusively to workers hired after certification and to low income workers. In addition, my analysis on the worker-level panel suggests that overall earnings growth in living wage firms lagged that in control firms over the observation period. This result is driven by relative declines in earnings for living wage workers in large firms and is attributed to increases in the published living wage rate that lags behind wage growth in the relevant segments of the job market.</p>

scholarly journals Composition and Activity of the Board of Directors: Impact on ESG Performance in the Banking System

2018 ◽  
Vol 10 (12) ◽  
pp. 4699 ◽  
Author(s):  
Giuliana Birindelli ◽  
Stefano Dell’Atti ◽  
Antonia Iannuzzi ◽  
Marco Savioli
Keyword(s):  
Board Of Directors ◽  
Fixed Effects ◽  
Critical Mass ◽  
Banking System ◽  
The United States ◽  
Fixed Effects Panel Regression ◽  
The Board Of Directors ◽  
Corporate Social ◽  
The Impact

A growing body of research suggests that the composition of a firm’s board of directors can influence its environmental, social and governance (ESG) performance. In the banking industry, ESG performance has not yet been explored to discover how a critical mass of women on the board of directors affects performance. This paper seeks to fill this gap in the literature by testing the impact of a critical mass of female directors on ESG performance. Other board characteristics are accounted for: independence, size, frequency of meetings and Corporate Social Responsibility (CSR) sustainability committee. We use fixed effects panel regression models on a sample of 108 listed banks in Europe and the United States for the period 2011–2016. Our main empirical evidence shows that the relationship between women on the board of directors and a bank’s ESG performance is an inverted U-shape. Therefore, the critical mass theory for banks is not supported, confirming that only gender-balanced boards positively impact a bank’s performance for sustainability. There is a positive link between ESG performance and board size or the presence of a CSR sustainability committee, while it is negative with the share of independent directors. With this work, we stress the key role of corporate governance principles in banks’ ESG performance, with relevant implications for both banks and supervisory authorities.

scholarly journals The Impact of Different Competitive Environments on Pacing and Performance

2018 ◽  
Vol 13 (6) ◽  
pp. 701-708 ◽  
Author(s):  
Marco J. Konings ◽  
Florentina J. Hettinga
Keyword(s):  
Fixed Effects ◽  
Linear Models ◽  
Real Life ◽  
Energy Resources ◽  
Mixed Linear Models ◽  
Start Position ◽  
Available Energy ◽  
Competitive Environments ◽  
And Performance ◽  
The Impact

Purpose: In real-life competitive situations, athletes are required to continuously make decisions about how and when to invest their available energy resources. This study attempted to identify how different competitive environments invite elite short-track speed skaters to modify their pacing behavior during head-to-head competition. Methods: Lap times of elite 500-, 1000- and 1500-m short-track speed skating competitions between 2011 and 2016 (N = 34,095 races) were collected. Log-transformed lap and finishing times were analyzed with mixed linear models. The fixed effects in the model were sex, season, stage of competition, start position, competition importance, event number per tournament, number of competitors per race, altitude, and time qualification. The random effects of the model were athlete identity and the residual (within-athlete race-to-race variation). Separate analyses were performed for each event. Results: Several competitive environments, such as the number of competitors in a race (a higher number of competitors evoked most likely a faster initial pace; coefficient of variation [CV] = 1.9–9.3%), the stage of competition (likely to most likely, a slower initial pace was demonstrated in finals; CV = −1.4% to 2.0%), the possibility of time qualification (most likely a faster initial pace; CV = 2.6–5.0%), and competition importance (most likely faster races at the Olympics; CV = 1.3–3.5%), altered the pacing decisions of elite skaters in 1000- and 1500-m events. Stage of competition and start position affected 500-m pacing behavior. Conclusions: As demonstrated in this study, different competitive environments evoked modifications in pacing behavior, in particular in the initial phase of the race, emphasizing the importance of athlete–environment interactions, especially during head-to-head competitions.

scholarly journals Could Government Data Openness Enhance Urban Innovation Capability? An Evaluation Based on Multistage DID Method

2021 ◽  
Vol 13 (23) ◽  
pp. 13495
Author(s):  
Yi Luo ◽  
Zhiwei Tang ◽  
Peiqi Fan
Keyword(s):  
Fixed Effects ◽  
Open Data ◽  
The United States ◽  
Data Accessibility ◽  
Open Government Data ◽  
The Matthew Effect ◽  
Innovation Ability ◽  
Government Data ◽  
Release Data ◽  
The Impact

The wave of government data opening has gradually swept the world since it rose from the United States in 2009. The purpose is not to open government data, but to release data value and drive economic and social development through data accessibility. At present, the impact of academic circles on government open data mostly stays in theoretical discussion, especially due to the lack of empirical tests. Using the multistage difference-in-difference (DID) model, this paper analyzes the panel data from 2009 to 2016 by taking two batches of Chinese cities with open data released in 2014 and 2105 as samples to test the impact of government data opening on urban innovation ability. The results show that the opening of government data significantly improves urban innovation abilities. After considering the heterogeneity and fixed effects of urban characteristics, the opening of government data still significantly improves urban innovation ability and shows a greater innovation driving role in cities with high levels of economic development, human capital, and infrastructure. Based on this, this paper believes that we should continue to promote the opening of government data, release the value of data, and pay attention to the Matthew effect between cities that may appear in the era of big data.

scholarly journals Did Trump's Tweet Disparaging Trudeau Impact Canada-U.S. Border Crossings?

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Emily Kane ◽  
Ariana Popa ◽  
Queenie Li ◽  
Paul Sommers
Keyword(s):  
United States ◽  
New York ◽  
Regression Analysis ◽  
Fixed Effects ◽  
Prime Minister ◽  
The United States ◽  
Border Crossings ◽  
Dummy Variables ◽  
International Border ◽  
The Impact

  The authors examine the impact of President Donald Trump’s June 9, 2018 tweet disparaging Group of 7 (G7) summit host Canadian Prime Minister Justin Trudeau on Canada – United States border crossings over the Peace Bridge.  The Peace Bridge is one of the busiest international border crossings in North America that connects Fort Erie, Ontario and Buffalo, New York.  A regression analysis of daily automobile crossings between January 1, 2017 and December 31, 2019 (using seasonality dummy variables and controlled for year fixed effects) revealed a statistically discernible reduction in the number of crossings (both east into the United States and, to a lesser extent, west into Canada) seven, fourteen, and even thirty days after the tweet.  Words have consequences. 

The Impact of State Firearm Laws on Homicide Rates among Black and White Populations in the United States, 1991–2016

2019 ◽  
Vol 44 (4) ◽  
pp. 232-240 ◽  
Author(s):  
Anita Knopov ◽  
Michael Siegel ◽  
Ziming Xuan ◽  
Emily F Rothman ◽  
Shea W Cronin ◽  
...  
Keyword(s):  
Fixed Effects ◽  
Black People ◽  
State Level ◽  
The United States ◽  
Homicide Rates ◽  
Black And White ◽  
Author Identification ◽  
Background Check ◽  
Black Populations ◽  
The Impact

Abstract This study aimed to investigate the potential differential effects of state-level firearm laws on black and white populations. Using a panel design, authors examined the relationship between state firearm laws and homicide victimization rates among white people and black people in 39 states during the period between 1991 and 2016. Authors modeled homicide rates using linear regression with year and state fixed effects and controlled for a range of time-varying, state-level factors. Results showed that universal background check laws and permit requirement laws were associated with lower homicide rates among both white and black populations, and “shall issue” laws were associated with higher homicide rates among both white and black populations. Laws that prohibit firearm possession among people convicted of a violent misdemeanor or require relinquishment of firearms by people with a domestic violence restraining order were associated with lower black homicide rates, but not with white homicide rates. Author identification of heterogeneity in the associations between state firearm laws and homicide rates among different racial groups has implications for reducing racial health disparities.

scholarly journals S28. ADVERSE CHILDHOOD EXPERIENCES AND PSYCHOTIC-LIKE EXPERIENCES ARE ASSOCIATED ABOVE AND BEYOND SHARED CORRELATES: FINDINGS FROM THE ADOLESCENT AND BRAIN COGNITIVE DEVELOPMENT (ABCD) STUDY

2020 ◽  
Vol 46 (Supplement_1) ◽  
pp. S41-S42
Author(s):  
Nicole Karcher ◽  
Tara Niendam ◽  
Deanna Barch
Keyword(s):  
Adverse Childhood Experiences ◽  
Internalizing Symptoms ◽  
Linear Models ◽  
The United States ◽  
Hierarchical Linear Models ◽  
Childhood Experiences ◽  
Treatment Pathways ◽  
Adverse Childhood ◽  
Increased Risk ◽  
The Relationship

Abstract Background Adverse childhood experiences (ACE) are associated with increased risk for schizophrenia spectrum symptoms, including PLEs. However, ACE and PLEs are also both associated with a several shared factors (i.e., stress, fluid cognition, internalizing symptoms, and suicidality). These factors, PLEs, and ACE may interrelate in complex ways, but research has not explicitly examined whether the association between ACE and PLEs remains over and above these shared correlates. This presentation will also examine evidence of PLEs mediating the associated between ACE and stress, fluid cognition, internalizing symptoms, suicidality or vice versus. Clarifying these interrelationships has important clinical implications, including understanding the mechanisms contributing to the development of PLEs and other negative psychopathological correlates. Methods The current study used hierarchical linear models to examine data from 10,800 9-11-year-olds from the ABCD study, recruited from 21 research sites across the United States. The analyses used hierarchical linear models (HLMs), with family unit and research site modeled as random intercepts, and age, sex, and race/ethnicity included as covariates. Child participants completed the Prodromal Questionnaire-Brief Child Version as a measure of PLEs. The ACE variable was defined as summations of parent-rated child experience of traumatic experiences from the Kiddie-Structured Assessment for Affective Disorders and Schizophrenia (KSADS) for DSM-5 and a demographic measure of financial adversity. In terms of shared correlates, internalizing symptoms and suicidality were measured using the KSADS, fluid cognition was measured using the NIH Toolbox, and stress was measured using the Child Behavior Checklist. Results Greater number of ACE were associated with greater PLEs (β=.102; 95% CI=0.083,0.120; p&lt;.001), including several specific ACE, including witnessing domestic violence [β=0.100; 95% CI=0.027,0.174; False Discovery Rate- Corrected (FDR)-corrected p=.04], traumatic grief (β=0.066; 95% CI=0.022,0.110; FDR-corrected p=.025), bullying (β=0.304; 95% CI=0.252,0.356; FDR-corrected p&lt;.001), and financial adversity (β=0.046; 95% CI=0.026,0.066; FDR-corrected p&lt;.001). Furthermore, specific types of PLEs (e.g., suspiciousness) are specifically associated with ACE. Importantly, ACE and PLEs were related even when accounting for shared correlates. Further, there is evidence that PLEs partially mediated the relationship between number of ACE and internalizing symptoms. Lastly, the presentation will provide evidence that PLEs partially mediated the relationship between number of ACE and suicidality, including that PLEs mediated and 58.74% of the association between ACE and suicidal behavior. Discussion The current presentation provides evidence that school-age PLEs are associated with adverse experiences in childhood over and above shared correlates, and helps clarify the nature of this association, including evidence for specificity both on the part of ACE and PLE. This work also indicates that PLEs mediate the association between trauma and both internalizing symptoms and suicidality, and some evidence for internalizing symptoms mediating the association between PLEs and ACE. This work has important implications regarding mechanisms underlying the development of negative psychological outcomes and implications for treatment pathways following trauma. Novel interventions that aim to address how PLEs mediate these associations, as well as interventions to reduce the distress and impairment associated with PLEs, could improve mental health outcomes in children and adolescents.

scholarly journals The Effect of Tour Leaders’ Emotional Intelligence on Tourists’ Consequences

2017 ◽  
Vol 58 (1) ◽  
pp. 63-76 ◽  
Author(s):  
Sheng-Hshiung Tsaur ◽  
Pi-Shen Ku
Keyword(s):  
Emotional Intelligence ◽  
Positive Affect ◽  
Empirical Data ◽  
Linear Models ◽  
Hierarchical Linear Models ◽  
Tourism Industry ◽  
Future Research ◽  
Management Implications ◽  
The Impact ◽  
Level Analysis

There has been little discussion on the impact of tour leaders’ emotional intelligence on tourists’ consequences although the study of emotional intelligence has gained attention in the tourism industry. Empirical data to assess emotional intelligence, affect, rapport, and customer satisfaction were collected from 54 tour leaders and 526 tour members participating in group package tours in Taiwan. Cross-level analysis with hierarchical linear models revealed that a tour leaders’ emotional intelligence could cultivate tour members’ positive affect and tour leader–member rapport, and lead to tourists’ satisfaction. Furthermore, the study discusses management implications and suggestions for future research.

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