scholarly journals Competition and cooperation in a synchronous bushcricket chorus

2014 ◽  
Vol 1 (2) ◽  
pp. 140167 ◽  
Author(s):  
M. Hartbauer ◽  
L. Haitzinger ◽  
M. Kainz ◽  
H. Römer
Keyword(s):  
Time Lag ◽  
Signal Amplitude ◽  
Choice Experiments ◽  
Competition And Cooperation ◽  
Ultimate Causation ◽  
Signal Period ◽  
Per Capita ◽  
High Degree ◽  
Leader Role ◽  
Leader Preference

Synchronous signalling within choruses of the same species either emerges from cooperation or competition. In our study on the katydid Mecopoda elongata , we aim to identify mechanisms driving evolution towards synchrony. The increase of signal amplitude owing to synchronous signalling and the preservation of a conspecific signal period may represent cooperative mechanisms, whereas chorus synchrony may also result from the preference of females for leading signals and the resulting competition for the leader role. We recorded the timing of signals and the resulting communal signal amplitudes in small choruses and performed female choice experiments to identify such mechanisms. Males frequently timed their signals either as leader or follower with an average time lag of about 70 ms. Females selected males in such choruses on the basis of signal order and signal duration. Two-choice experiments revealed a time lag of only 70 ms to bias mate choice in favour of the leader. Furthermore, a song model with a conspecific signal period of 2 s was more attractive than a song model with an irregular or longer and shorter than average signal period. Owing to a high degree of overlap and plasticity of signals produced in ‘four male choruses’, peak and root mean square amplitudes increased by about 7 dB relative to lone singers. Modelling active space of synchronous males and solo singing males revealed a strongly increased broadcast area of synchronous signallers, but a slightly reduced per capita mating possibility compared with lone singers. These results suggest a strong leader preference of females as the ultimate causation of inter-male competition for timing signals as leader. The emerging synchrony increases the amplitude of signals produced in a chorus and has the potential to compensate a reduction of mating advantage in a chorus. We discuss a possible fitness benefit of males gained through a beacon effect and the possibility that signalling as follower is stabilized via natural selection.

scholarly journals Marketing, management and financial providing of affordable housing

2021 ◽  
Vol 5 (2) ◽  
pp. 213-230
Author(s):  
Svitlana Ianchuk ◽  
Olga Garafonova ◽  
Yuliia Panimash ◽  
Dariusz Pawliszczy
Keyword(s):  
Housing Market ◽  
Affordable Housing ◽  
Social Housing ◽  
Time Lag ◽  
Generalized Method Of Moments ◽  
Housing Prices ◽  
Marketing Management ◽  
Gdp Per Capita ◽  
Local Authorities ◽  
Per Capita

Today’s rising housing prices in most countries worldwide have caused increasable attention to the problem of affordable housing. It is a social or ethical issue and an essential economic direction. Thus, affordable housing has great potential, influencing economic growth, labor forces, innovation, sustainable development, and an inclusive economy. Systematization of informational sources, theoretical and practical approaches for providing affordable housing, and assessing social housing needs indicated many views on this problem among scholars and policymakers. That is why marketing, management, and financial providing of affordable housing are significant mainstreams. The research aims to investigate marketing and management fundamentals of providing affordable housing in connection with funding aspects based on cross-country analysis. For achieving this target, key trends of housing market segmentation were analyzed, considering the distribution of the population by tenure status and analytical house price indicators using the data of the statistical office of the EU, the World Bank, and the OECD. The ways to promote more affordable housing by public and local authorities, private investors in affordable housing, and specific social and affordable housing market organizations were described. Main organizational forms of providing affordable and social housing were also characterized. Particular attention was paid to strategic planning for affordable and social housing, especially housing business plans or affordable housing strategy development as a priority step in marketing, management, and financial providing affordable housing. A SWOT analysis for affordable housing developments was used to show strengths, weaknesses, opportunities, and threats to the affordable housing market. To empirically confirm some relevant strengths, the impact of indicators of financial providing of affordable housing was formalized based on correlation analysis (calculating Pearson or Spearman correlation coefficients with time lags based on results of Shapiro-Wilk testing) and construction of Arellano–Bond linear dynamic panel-data regression model with checking the Sargan test of overidentifying restrictions (the sample from 25 EU countries for 2011–2019) using the Excel 2010 and STATA 14.2 software. The dynamic model made it possible to consider the share of affordable housing owners with mortgage or loan or the share of tenants, rent affordable housing at a reduced price or free. The value of GDP of the previous period affects the current situation (due to introducing lag variables and using instrumental variables or the generalized method of moments (GMM) to obtain adequate estimates). The hypothesis that an increase of 1% of the share of affordable housing owners with mortgage or loan causes the rise in GDP per capita of an average of 0.44% with a two-year time lag was empirically confirmed. An increase of 1% of the share of tenants, rent-free housing or affordable housing at the reduced price, causes the decrease of GDP per capita of an average of 0.5% with a two-year time lag. It was substantiated that governments should continue and improve their policies for financing social and affordable housing. At the same time, they should prefer affordable mortgage lending programs over programs of reduced or free rental housing. The results of this research confirm the significant drivers of policies and practices devoted to affordable and social housing, such as marketing, management, and financial providing. The presented recommendations are useful for scholars interested in this scientific field of research, public and local authorities, investors in affordable housing, and specific affordable and social housing organizations.

scholarly journals HIV/AIDS and Economic Growth: Empirical Evidence from Sub-Saharan Africa

2015 ◽  
Vol 7 (4) ◽  
pp. 30 ◽  
Author(s):  
Danjuma Maijama'a ◽  
Shamzaeffa Samsudin ◽  
Shazida jan Mohd Khan
Keyword(s):  
Economic Growth ◽  
Time Lag ◽  
Hiv And Aids ◽  
Sub Saharan Africa ◽  
Growth Equation ◽  
Solow Model ◽  
African Countries ◽  
Negative Effect ◽  
Per Capita ◽  
Sub Saharan

<p>This study investigates the effects of the HIV and AIDS epidemic on economic growth in 42<br />sub-Saharan African countries using data spanning from 1990-2013. Unlike previous studies,<br />we use a longer data horizon and take the time lag effect of the epidemic’s incubation period<br />that is, after it might have developed to AIDS into consideration in our estimations. We<br />estimated an empirical growth equation within an augmented Solow model and applied the<br />dynamic system GMM estimator. The results suggest that current HIV prevalence rate –<br />associated with rising morbidity, has a negative effect on GDP per capita growth, conversely<br />AIDS – associated with higher mortality in addition to morbidity, increases per capita GDP<br />growth.</p>

Theoretical and Practical Implications of I.M.F. Conditionality in Zambia

1986 ◽  
Vol 24 (3) ◽  
pp. 395-422 ◽  
Author(s):  
Neva Seidman Makgetla
Keyword(s):  
Low Income ◽  
Terms Of Trade ◽  
Living Standards ◽  
Real Wages ◽  
Colonial Era ◽  
Income Groups ◽  
Low Income Groups ◽  
Per Capita ◽  
High Degree ◽  
Practical Implications

Zambia has faced an economic crisis since 1975. Living standards for most of the population have deteriorated sharply, with falling real wages and a drop in G.D.P. per capita by about a quarter. At the same time, the gap between the high- and low-income groups has probably widened.Zambia's economic difficulties originated in international factors. In the two decades of independence, and unusually high degree of external dependency, inherited from the colonial era, continued to chatacterise the economy. Imported inputs accounted for at least one-third of all costs in mining and manufacturing, as may be seen from Table I. Meanwhile, the production of copper and relate minerals contributed a steady nine-tenths of export revenues. But in 1975, the terms of trade for copper plummeted by nearly 50 per cent, and merchandise imports promptly contracted by almost one-quarter, seriously affecting production. Since then the price of copper has stagnated.

scholarly journals Econometric Analysis of Sustainable National Economy Development

2020 ◽  
Keyword(s):  
Sustainable Development ◽  
Sulfur Dioxide ◽  
Growth Rates ◽  
Capita Income ◽  
Time Lag ◽  
Hazardous Substances ◽  
Gdp Growth ◽  
Per Capita Income ◽  
Per Capita

Purpose. The study objective was to model conditions, mechanisms and opportunities to achieve sustainable development parameters for the national economy. Меthods. Analysis and synthesis, induction and deduction, analytical grouping and special (abstraction, modelling, etc.) methods of studying economic phenomena and processes have been used. Results. Based on the analysis of the dynamics of GDP growth rates, sulfur dioxide, nitrogen dioxide, oxide and carbon dioxide emissions during 1991-2017, the cycle of their change lasting 3 - 5 years has been proved. It has been found out that the Environmental Kuznets Curve (EKC) in Ukraine is a specific one due to the "turning points". According to the results of comparing the cyclicality of per capita income growth rates, GDP indexes with the dynamics of dependence between the hazardous substances emissions and per capita income and GDP in actual prices, it is found that they do not always coincide. It gives grounds to make a conclusion about the presence of lag between the emissions volumes changes and values of per capita income and GDP in actual prices. The conclusions are grounded on the comparison of the dynamics of GDP growth rates, income per capita, pollutant emissions and the parameters of their mutual correlation. It has been proposed to carry out coordinated policy referring its economic, social and environmental components, taking into account the time lag to create the conditions for the EKC curve parameters in the economy of Ukraine. Conclusions. . Based on the analysis of GDP growth rates dynamics, sulfur dioxide, nitrogen dioxide, carbon oxide and dioxide emissions, the periodicity (cyclicality) of their change has been proved. In Ukraine, EKC has a specific nature in the form of separate «turning points», without achievement of long-term parameters of the relationship between the hazardous substances emissions and GDP and per capita income values. Thus, the feasibility of developing the agreed policy concerning the economic (GDP value), social (population income level) and environmental components (conservation activity financing and decrease of hazardous substances emissions) taking into account the time lag, which will create the conditions for achieving not only temporary values, but also long-term parameters of EKC curve in the Ukrainian economy, was substantiated. The obtained results allow to forecast sustainable development parameters of Ukraine for the future.

scholarly journals A Method of m-Point Sinusoidal Signal Amplitude Estimation

2016 ◽  
Vol 16 (5) ◽  
pp. 244-253
Author(s):  
Sergiusz Sienkowski
Keyword(s):  
Signal Amplitude ◽  
Original Method ◽  
Point Estimation ◽  
Sinusoidal Signal ◽  
Initial Signal ◽  
Amplitude Estimation ◽  
Starting Point ◽  
Special Cases ◽  
Point Estimator ◽  
Signal Period

Abstract The paper presents a new and original method of m-point estimation of sinusoidal signal amplitude. In this method, an m-point estimator is calculated on the basis of m initial signal samples. The way the estimator is constructed is explained. It is shown that the starting point for constructing the estimator is two initial signal samples. Next, in order to determine the estimator general form, three and m subsequent initial signal samples appearing in a signal period are used. Some special cases of an estimator are considered. Such an estimator is compared with a four-point estimator proposed by Vizireanu and Halunga. It is shown that the m-point estimator makes it possible to estimate the signal amplitude more accurately.

scholarly journals Economic Inequalities And The Level of Decentralization In European Countries: Cluster Analysis

2016 ◽  
Vol 19 (4) ◽  
pp. 27-46 ◽  
Author(s):  
Šárka Labutková ◽  
Pavla Bednářová ◽  
Vladimíra Hovorková Valentová
Keyword(s):  
Human Development Index ◽  
European Countries ◽  
Gdp Per Capita ◽  
Multidimensional Inequality ◽  
Distribution Of Wealth ◽  
Per Capita ◽  
Economic Imbalances ◽  
High Degree ◽  
Development Gap ◽  
Economic Inequalities

This submitted article identifies relations between the degree of decentralization and economic imbalances on the basis of a cluster (exploratory) analysis. Two indicators have been chosen for measuring economic inequalities: an indicator of dispersion of regional GDP per capita as representative of the performance imbalances within countries (it measures the economic development gap among regions in European countries); and a multidimensional inequality-adjusted human development index as representative of inequalities in the distribution of wealth in the countries. Decentralization is measured by means of a decentralization index, which contains both quantitative and qualitative components. Although groups of countries characterised by a high degree of decentralization do not necessarily show the lowest degrees of economic imbalances, it is however possible to conclude that the countries in groups with a higher degree of decentralization are among those countries with more favourable values of the economic imbalances indicators monitored. As a part of the research, two clusters of countries were identified which are identical in their degree of decentralization, but differ in the results connected with economic imbalances. The differences are caused by different institutional qualities in the two groups.

scholarly journals Innovation Financing Structure as a Factor of Economic Growth: Cross Country Analysis

2020 ◽  
pp. 133-156
Author(s):  
Anar Rzayev ◽  
Anastasiia Samoilikova
Keyword(s):  
Economic Growth ◽  
Dynamic Model ◽  
Least Squares Method ◽  
Time Lag ◽  
Time Lags ◽  
Business Sector ◽  
Distribution Law ◽  
Financing Structure ◽  
Government Sector ◽  
Per Capita

The article focuses on the level and dynamics of innovation financing in Azerbaijan and Ukraine compared to the world level and the places of Azerbaijan and Ukraine in the Global Innovation Index and trends in their positioning in the dynamics. The analysis reveals negative dynamics in both countries in this sphere. The innovation financing structure's role as a factor of economic growth and international reproductive relations development is substantiated. The dependence of the country's economic growth level (GDP growth per capita) on the value of expenditures on innovation financed by various sectors of the economy (government, the private non-profit sector, foreign investors and the higher education sector) is studied. The study consists of data for 12 European countries for 2007-2017 (limited calculations in 2017 due to the availability of information on open portals of the World Bank, the EU Statistical Office). At the first stage, the distribution of the relevant indicators was evaluated using the Shapiro-Wilk test. Based on these results the method of calculating the correlation coefficient is chosen: Pearson – for indices that are subject to the ordinary distribution law or Spearman – for indices that are not subject to the ordinary distribution law. A correlation analysis regarding the strength and nature of the relationship between relevant indices and the dynamics of GDP per capita in these countries is performed to identify the duration of time lags, after which this relationship is the most statistically significant. In the second stage, there are three types of regression models for estimating panel data to identify the impact on the economic growth dynamics of innovations financed by different economic sectors: 1) with fixed effects (based on the least-squares method); 2) with random effects (based on the general least squares method (GLS); 3) dynamic model for estimation of Arellano-Bond panel data, which considers time lags (based on the general method of moments (GMM)). In the third stage, using Wald's tests, Breusch-Pagan and Hausman, the adequate model specification is chosen. When choosing a dynamic model of Arellano-Bond, the Sargan test is performed to validate the parameters. The control variables in all three types of models consider net inflows and outflows of foreign investment, inflation (GDP deflator) and labour force participation rate (% of total population ages 15-64). The second and third stages of the study obtained the results as follows. It is empirically confirmed that a 1% increase in the share of government sector-funded R&D expenditures leads to a decrease in annual GDP growth per capita by an average of 0.15% (excluding time), business sector – to the increase by 0.13% with a time lag of 2 years, thanks to foreign sources – to the increase by 0.1% (without time lag); higher education sector – to the decrease by 0.78% (without time lag). It is substantiated that the state should reduce the share of direct investment in innovation. At the same time, it should focus on effective legislation, motivating the business sector and foreign investors to increase investment in research and development to stimulate economic growth in Azerbaijan and Ukraine and the development of international reproductive relations. Keywords business sector, correlation analysis, dynamic model, economic growth, financial regulations, financing structure, foreign sources, GERD, government sector, influence formalization, innovation, regression model, R&D.

An evaluation of two indices of red fox (Vulpes vulpes) abundance in an arid environment

2001 ◽  
Vol 28 (4) ◽  
pp. 419 ◽  
Author(s):  
Andy Sharp ◽  
Melinda Norton ◽  
Adam Marks ◽  
Kerry Holmes
Keyword(s):  
Population Size ◽  
Food Supply ◽  
Vulpes Vulpes ◽  
Red Fox ◽  
Time Lag ◽  
Arid Environment ◽  
Statistical Detection ◽  
Two Indices ◽  
High Degree ◽  
Suitable Measure

The suitability of spotlight counts to index red fox abundance was assessed in an arid environment through a comparison with a scat deposition index (active attractant). In most cases there was a high degree of correlation between the two indices, suggesting that the spotlight counts were accurately documenting fluctuations in population size. However, the precision of the spotlight index was often low (c.v. = 0.07–0.46), suggesting that the technique may not allow the statistical detection of small changes in abundance. During periods when there was an influx of new individuals into the population, the seasonal scat index displayed a three-month time lag in documenting abundance while foxes accustomed themselves to the presence of the regular food supply. The level of precision of the scat index was also found to be relatively low (c.v. = 0.21–0.48). Nevertheless, further refinements of this technique may produce a suitable measure of fox abundance.

Scotland's Economic Performance and the Fiscal Implications of Moving to Independence

2014 ◽  
Vol 227 ◽  
pp. R3-R13 ◽  
Author(s):  
John McLaren ◽  
Jo Armstrong
Keyword(s):  
North Sea ◽  
Economic Performance ◽  
Oil And Gas ◽  
Current Level ◽  
Gdp Per Capita ◽  
Fiscal Balance ◽  
Per Capita ◽  
The Uk ◽  
High Degree ◽  
Fiscal Implications

Scotland's economic performance and fiscal make-up are key elements in the debate leading up to the forthcoming referendum on independence. However, in terms of understanding Scotland's economic performance, the situation is complicated by the high degree of overseas ownership, especially with regards to North Sea activity, and the importance of a natural commodity, oil. This makes the use of traditional measures of economic performance, like GDP or GDP per capita, less relevant than for most countries and suggests a greater need to use both constant price and cash GNI, neither of which are currently available. In terms of its fiscal balance, Scotland's independence would require taxes derived from its offshore (North Sea) activity to be sufficient to offset the extra monies (in per head terms) currently transferred from the rest of the UK (via the Barnett formula system) in order to pay for the current level of public services. Based on current projections, such North Sea related tax revenues would amount to less than the likely Barnett transfer, leading to a net loss in funding at the time of independence. Under such circumstances the question of whether or not Scotland could afford to initiate the building up of an ‘Oil Fund’, is largely a redundant one. However, uncertainties over both future oil and gas revenues and over the continuation of the existing Barnett system make it difficult to predict with any great certainty whether Scotland would see a longer-term net fiscal gain or loss post-independence. Apparent inconsistencies between official GNI and Scottish revenue figures also means that the existing fiscal balance position remains open to question.

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