Two Problems of Averaging Arising in the Estimation of the Relationship Between Accidents and Traffic Flow

1998 ◽  
Vol 1635 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Abraham Mensah ◽  
Ezra Hauer
Keyword(s):  
Traffic Flow ◽  
Annual Average ◽  
Performance Function ◽  
Safety Performance Function ◽  
Time Period ◽  
Annual Average Daily Traffic ◽  
Averaging Problem ◽  
Long Time ◽  
The Relationship ◽  
The Ideal

A function linking the expected accident frequency to traffic flow is called a safety performance function (SPF). SPFs are estimated from data for various facilities and accident types. Typically, accident counts over a period of a year or more, and estimates of average flow for such periods, serve as data. The ideal is for SPFs to represent cause-effect regularities. However, because accident counts are for a long time period and because average flows are used, two issues of averaging arise. First, the cause-effect relationship is between accidents and the flows prevailing near the time of accident occurrence. Therefore, ideally, these should be the argument of the SPF. In practice, however, either because of lack of detail or difficulties of estimation, average flows are used for estimation. The question is what problems arise when average flows, such as annual average daily traffic, instead of the flows at the time of the accident are used as the argument of the SPF. This is the argument averaging problem. Second, there are at least two (daytime and nighttime) and perhaps many more cause-effect SPFs that prevail in the course of a year. Ideally, each relationship should be estimated separately. The question is what problems arise if one joint SPF is estimated when two or more separate functions should have been used. This is the function averaging problem. After analysis, how to account and how to correct for the argument averaging problem are shown. At this time, avoiding the function averaging problem by estimating daytime and nighttime SPFs separately can be the only recommendation.

scholarly journals Are stock returns an inflation hedge for the UK? Evidence from a wavelet analysis using over three centuries of data

2018 ◽  
Vol 23 (3) ◽  
Author(s):  
Aviral Kumar Tiwari ◽  
Juncal Cunado ◽  
Rangan Gupta ◽  
Mark E. Wohar
Keyword(s):  
South Africa ◽  
Wavelet Analysis ◽  
Stock Returns ◽  
Time Period ◽  
Inflation Rates ◽  
The Us ◽  
Long Time ◽  
Time Periods ◽  
The Uk ◽  
The Relationship

Abstract This paper analyzes the relationship between stock returns and the inflation rates for the UK over a long time period (February 1790–February 2017) and at different frequencies, by employing a wavelet analysis. We also compare the results for the UK economy with those for the US and two developing countries (India and South Africa). Overall, our results tend to suggest that, while the relationship between stock returns and inflation rates varies across frequencies and time periods, there is no evidence of stock returns acting as an inflation hedge, irrespective of whether we look at the two developed or the two developing markets in our sample.

,,Ein Vorhof zum Paradies". Das Czernowitz-Bild in der deutsch-jüdischen Literatur

2006 ◽  
Vol 58 (3) ◽  
pp. 216-226
Author(s):  
Anna-Dorothea Ludewig
Keyword(s):  
20Th Century ◽  
19Th Century ◽  
Holocaust Survivors ◽  
The Real ◽  
Real Place ◽  
Time Period ◽  
The 19Th Century ◽  
The Relationship ◽  
The Ideal

AbstractThe present research on Czernowitz focuses mostly on the 20th century and on the works and memoirs of Holocaust survivors. But Czernowitz was at its cultural and economical height at the end of the 19th century, and it was during that time that the myth of the ,,ideal city" was established. This essay stresses the importance of that time period for understanding the ,,Czernowitz myth," and it analyzes the relationship between the ,,real" place Czernowitz and the literary topos of a ,,sunken city" (Rose Ausländer).

Identifying Locations with Potential for Accident Reductions: Use of Direct Diagnostics and Pattern Recognition Methodologies

2002 ◽  
Vol 1784 (1) ◽  
pp. 153-158 ◽  
Author(s):  
Jake Kononov
Keyword(s):  
Pattern Recognition ◽  
Safety Performance ◽  
Performance Function ◽  
Safety Performance Function ◽  
Lighting Conditions ◽  
Road Section ◽  
Annual Average Daily Traffic ◽  
Safety Performance Functions ◽  
Pattern Recognition Analysis ◽  
The Many

Safety performance functions reflect the complex relationship between exposure, usually measured in annual average daily traffic, and accident count for a unit of road section over a unit of time. One of the main uses of the safety performance functions is to identify locations that experience more accidents than expected, thus exhibiting a potential for accident reduction. Overrepresentation in the number of accidents above the expected or normal threshold predicted by the safety performance function is only one of many indicators of a potential for accident reduction. Accident type, severity, road condition, spatial distribution of accidents, and lighting conditions are only a few of the many important symptoms of the accident problem. Two methodologies are introduced for identification of locations with potential for accident reduction: direct diagnostics and continuous pattern recognition analysis. Use of these methodologies revealed that existence of accident patterns susceptible to correction may or may not be accompanied by the overrepresentation in accident frequency detected by the safety performance functions.

scholarly journals PEREMPUAN MINANGKABAU DALAM PANGGUNG POLITIK

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Lindayanti Lindayanti
Keyword(s):  
Community Structure ◽  
Education Level ◽  
Indigenous Community ◽  
The Political ◽  
Central Position ◽  
Political Arena ◽  
Unique Role ◽  
Long Time ◽  
The Relationship ◽  
The Ideal

Women in the Minangkabau indigenous community structure have a unique role. In the Minangkabau matrilineal custom system, women are placed ina central position. Minangkabau women have been portrayed as having played arole in the political arena in Minangkabau for a long time. This can be seen fromclassic Minangkabau stories such as kaba, tambo or myth. Many stories ofwomen's heroism are found. What is the relationship between the ideal level andreality in the politics of Minangkabau women? For example, "Keagungan BundoKanduang" depicted in the story of Cindur Mato from an ideal level coupled withMinangkabau women performing in various fields such as Putri Rahmah elYunusiyah also established several other women's schools as an effort to increasethe education level of women in Minangkabau.

scholarly journals An Assessment of House Loans Cointegration with Macro Variables in Selected Euro Zone Countries

Ekonomika ◽  
2020 ◽  
Vol 99 (2) ◽  
pp. 39-58
Author(s):  
Kazys Kupčinskas ◽  
Arvydas Paškevičius
Keyword(s):  
Interest Rates ◽  
Correction Model ◽  
Monthly Data ◽  
Vector Error Correction ◽  
Vector Error ◽  
Time Period ◽  
Long Time ◽  
Macro Variables ◽  
The Relationship

This paper performs an empirical study on house loans, interest rates, unemployment, and house rent prices relationship in Germany, France, Spain and Italy from the year 2003 to 2018. We look for the cointegration and causality relationship between the house loans and macro variables with the help of the Vector error correction model (VECM) and Granger causality methods. We investigate whether variables with monthly data explain better the relationship and causal effects between the variables. We find a long term cointegrating relationship between the real house loans and interest rates, unemployment and house rent prices for France, Spain, and Italy, but not for Germany. On average the equilibrium in house loan development is reached from 4 to 8 years, meaning that long term equilibrium exists, but the variables reach it in a rather long time period. The ECB deposit facility rate included as an exogenous variable in four countries gained no significant power in explaining the short term changes of house loans in any of the country. We reveal a complex interaction between the bank’s credits and unemployment, interest rates, house rental prices in the paper. 

Level of Service of Safety: Conceptual Blueprint and Analytical Framework

2003 ◽  
Vol 1840 (1) ◽  
pp. 57-66 ◽  
Author(s):  
Jake Kononov ◽  
Bryan Allery
Keyword(s):  
Conceptual Development ◽  
Analytical Framework ◽  
Level Of Service ◽  
Specific Level ◽  
Performance Function ◽  
Safety Problem ◽  
Safety Performance Function ◽  
Highway Safety Manual ◽  
Accident Frequency ◽  
Annual Average Daily Traffic

While some initial and significant progress has been made in the development of a highway safety manual, much remains to be done in the areas of conceptual development and the diagnostics of safety problems. The concept of level of service of safety (LOSS) in the framework of safety performance function is introduced, and the problem of diagnostics is addressed. LOSS reflects how the roadway segment is performing in regard to its expected accident frequency and severity at a specific level of annual average daily traffic. It provides a comparison of accident frequency and severity only with the expected norms; it does not, however, provide any information related to the nature of the safety problem itself. If the safety problem is present, LOSS will describe only its magnitude. The nature of the problem is determined through diagnostic analysis by direct diagnostics and pattern recognition techniques, which are also discussed.

scholarly journals Estimating the Safety Performance Function for Urban Unsignalized Four-Legged One-Way Intersections in Palermo, Italy

2014 ◽  
Vol 60 (1) ◽  
pp. 41-54 ◽  
Author(s):  
O. Giuffrè ◽  
A. Granà ◽  
T. Giuffrè ◽  
R. Marino ◽  
S. Marino
Keyword(s):  
Predictive Model ◽  
Traffic Flow ◽  
Generalized Estimating Equations ◽  
Geometric Design ◽  
Safety Performance ◽  
Correlation Matrices ◽  
Performance Function ◽  
Safety Performance Function ◽  
Unsignalized Intersections ◽  
Working Correlation

Abstract Starting from consideration that urban intersections are sites with promise for safety and operational improvements, the paper describes the steps taken to develop a crash predictive model for estimating the safety performance of urban unsignalized intersections located in Palermo, Italy. The focus is on unsignalized four-legged one-way intersections widespread in Italian downtowns. The sample considered in the study consist of 92 intersections in Palermo, Italy. For the study were collected crashes occurred in the sites during the years 2006-2012, geometric design and functional characteristics and traffic flow. Results showed that data were overdispersed and NB1 distributed. In order to account for the correlation within responses Generalized Estimating Equations (GEE) were used under different working correlation matrices.

scholarly journals Impact of Road Fencing on Ungulate–Vehicle Collisions and Hotspot Patterns

Land ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 338
Author(s):  
Andrius Kučas ◽  
Linas Balčiauskas
Keyword(s):  
Traffic Accidents ◽  
Road Traffic ◽  
Mitigation Measures ◽  
Traffic Intensity ◽  
Road Traffic Accidents ◽  
Annual Average ◽  
Vehicle Collisions ◽  
Vehicle Collision ◽  
Annual Average Daily Traffic ◽  
The Relationship

The number of road traffic accidents decreased in Lithuania from 2002 to 2017, while the ungulate–vehicle collision (UVC) number increased and accounted for approximately 69% of all wildlife–vehicle collisions (WVC) in the country. Understanding the relationship between UVCs, traffic intensity, and implemented mitigation measures is important for the assessment of UVC mitigation measure efficiency. We assessed the effect of annual average daily traffic (AADT) and wildlife fencing on UVCs using regression analysis of changes in annual UVCs and UVC hotspots on different categories of roads. At the highest rates, annual UVC numbers and UVC hotspots increased on lower category (national and regional) roads, forming a denser network. Lower rates of UVC increase occurred on higher category (main) roads, forming sparser road networks and characterized by the highest AADT. Before 2011, both UVC occurrence and fenced road sections were most common on higher-category roads. However, as of 2011, the majority of UVCs occurred on lower-category roads where AADT and fencing had no impact on UVCs. We conclude that wildlife fencing on roads characterized by higher speed and traffic intensity may decrease UVC numbers and at the same time shifting UVC occurrence towards roads characterized by lower speed and traffic intensity. Wildlife fencing re-allocates wildlife movement pathways toward roads with insufficient or no mitigation measures.

The Problem of Identifying and Modeling the Relationship between Monetary Factor and Inflation in the Russian Economy

2008 ◽  
pp. 61-76
Author(s):  
A. Porshakov ◽  
A. Ponomarenko
Keyword(s):  
Money Supply ◽  
Money Demand ◽  
Russian Economy ◽  
Long Run ◽  
Complex Approach ◽  
Wide Range ◽  
Long Time ◽  
The Relationship ◽  
Supply Side Factors

The role of monetary factor in generating inflationary processes in Russia has stimulated various debates in social and scientific circles for a relatively long time. The authors show that identification of the specificity of relationship between money and inflation requires a complex approach based on statistical modeling and involving a wide range of indicators relevant for the price changes in the economy. As a result a model of inflation for Russia implying the decomposition of inflation dynamics into demand-side and supply-side factors is suggested. The main conclusion drawn is that during the recent years the volume of inflationary pressures in the Russian economy has been determined by the deviation of money supply from money demand, rather than by money supply alone. At the same time, monetary factor has a long-run spread over time impact on inflation.

KONSTRUKSI ISLAM DALAM KEKUASAAN NEGARA

1970 ◽  
Vol 6 (2) ◽  
Author(s):  
Nurul Aini Musyarofah
Keyword(s):  
Islamic Law ◽  
Social Condition ◽  
The Other ◽  
Good Society ◽  
Ideal Form ◽  
Other Hand ◽  
Islamic Politics ◽  
The Relationship ◽  
The Ideal

The relationship between Islam and state raises a controversy that includes two main groups;formalists and substantialists. Both of them intend to achieve a good social condition which is inaccordance with Islamic politics. The ideal form of good society to be achieved is principallydescribed in the main source of Islamic law, Al Qur’an and As Sunnah, as follows. A form of goodsociety should supprot equality and justice, egalitarianism, and democracy in its social community.The next problem is what the needed methods and instruments to achieve the ideal Islamic politicsare. In this case, the debate on the formalization and substance of Islamic teaching is related to therunning formal political institution.Each group claims itself to be the most representative to the ideal Islam that often leads to anescalating conflict. On the other hand thr arguments of both groups does not reach the wholeMuslims. As a result, the discourse of Islam and state seems to be elitist and political. As a result,Both groups suspect each other each other and try to utilize the controversy on the relationshipbetween Islam and state to get their own benefit which has no relation with the actualization ofIslamic teaching.

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