DATA REDUCTION BY THE HAAR FUNCTION: A CASE STUDY OF THE PHILLIPS CURVE

2021 ◽  
pp. 1-18
Author(s):  
Marco Gallegati ◽  
Meghnad Desai ◽  
James B. Ramsey

The unorthodox estimation procedure, which Phillips (1958) adopted in his original paper, is examined using the Haar wavelet filter. The application of the Haar wavelet transform to Phillips’ original data shows that Phillips’ six pairs of mean coordinates display a striking similarity with the Haar scaling coefficients that represent averages with a period greater than 16 years. This is consistent with Desai’s (1975) intuition on the interpretation of the Phillips Curve. We show that the choice of sorting observations by ascending values of the unemployment rate is crucial for reaching the goal of estimating the eye-catching nonlinear hyperbolic shape of the wage–unemployment relationship that would be otherwise linear. Interestingly, the Haar filter can account not only for the facts characterizing the Phillips’ relationship up to the early 1960s but also for two important facts mostly debated among policymakers: the downward shift of the Phillips Curve and its flattening over time.

2020 ◽  
Vol 21 (1) ◽  
pp. 5-21
Author(s):  
Lars Stehn ◽  
Susanne Engström ◽  
Petri Uusitalo ◽  
Rita Lavikka

Purpose To further the understanding of industrialised house building (IHB) from a temporal, emergent corporate-ability perspective, this study aims to trace the build-up of corporate assets in an IHB company over time. The research draws on dynamic capabilities, acknowledging not only what assets the company have developed and currently are exploiting, but also how these assets were develop and managed (i.e. enhanced, combined, protected and potentially reconfigured) to sustain long-term competitiveness. Design/methodology/approach A case study design was used to form a narrative that covers the evolution of an IHB company over a 25-year period. Corporate archival material, analysis of original data from a large number of research studies during 1993-2013 and retrospective reflections of owners and managers, including crosschecking interpretations of archival material, developed and triangulated the narrative. Findings The study presents rich empirical findings on the build-up of corporate assets. Starting from a successive process of exploration and exploitation formation of dynamic capabilities eventually played out into an exponential dynamic capability build-up. The IHB case company displays the ability to not only continuously exploit and renew resources and competences, but also to sense, seize and reconfigure cumulative assets over time. The exponential development of dynamic capabilities resonates to literature on higher-order dynamic capabilities implying that: the accumulated and higher-order dynamic capabilities are difficult to imitate and a (any) company must possess higher-order dynamic capabilities to be able to exploit and/or take up IHB. Originality/value The study is complementing and potentially challenging frequent framings of the IHB concept. Previous research has addressed and characterised IHB mainly by encapsulating a moment in time and, thus, characteristics are momentary and represent static views on IHB. However, IHB has seen a strong development over the past 25 years, and the study reflects on this development from the perspective of one of the IHB-forerunner companies in Sweden. By exploring from a company perspective the developments, reconfiguration and capacity to develop/reconfigure over time in a changing environment, the study introduces an alternative understanding of IHB as dynamic capabilities.


2018 ◽  
Vol 28 (2) ◽  
Author(s):  
T Dowling ◽  
Somikazi Deyi ◽  
Anele Gobodwana

While there have been a number of studies on the decontextualisation and secularisation of traditional ritual music in America, Taiwan and other parts of the globe, very little has been written on the processes and transformations that South Africa’s indigenous ceremonial songs go through over time. This study was prompted by the authors’ interest in, and engagement with the Xhosa initiation song Somagwaza, which has been re-imagined as a popular song, but has also purportedly found its way into other religious spaces. In this article, we attempted to investigate the extent to which the song Somagwaza is still associated with the Xhosa initiation ritual and to analyse evidence of it being decontextualised and secularised in contemporary South Africa. Our methodology included an examination of the various academic treatments of the song, an analysis of the lyrics of a popular song, bearing the same name, holding small focus group discussions, and distributing questionnaires to speakers of isiXhosa on the topic of the song. The data gathered were analysed using the constant comparative method of analysing qualitative research.


2002 ◽  
Vol 78 (4) ◽  
pp. 539-549 ◽  
Author(s):  
Paul D Anderson ◽  
John C Zasada ◽  
Glen W Erickson ◽  
Zigmond A Zasada

A white pine (Pinus strobus L.) stand at the western margin of the species range, approximately 125 years of age at present, was thinned in 1953 from 33.5 m2 ha-1 to target residual basal areas of 18.4, 23.0, 27.5, and 32.1 m2 ha-1 . Repeated measurement over the following 43-years indicated that the greatest total volume production and the greatest number of large diameter trees occurred in the unit of highest residual density. Over time, the distribution of stems was predominantly random although mortality between 1979 and 1996 resulted in a tendency for clumping in the 23.0 and 27.5 m2 ha-1 treatments. DNA analysis indicated that thinning intensity had little effect on the genetic diversity of residual white pine. This study suggests that mature white pine stands in northern Minnesota may be managed at relatively high densities without loss of productivity. However, regardless of overstory density, there was little or no white pine regeneration occurring in this stand. Key words: thinning, growth, genetic diversity, molecular markers, spatial pattern, regeneration


2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Mohammed Awadh Jasim ◽  
Laura Hanks ◽  
Katharina Borsi

AbstractToday, the concept of built heritage authenticity is a projection screen for conflicting demands and thus a ‘contested field’. Short-sighted readings started to drag the concept behind different ill-considered treatises, in which some heritage aspects loosely outweighed other aspects. Archaeological perspectives that tend to freeze heritage structures in time, such as those that are privileged upon other contemporary socio-cultural issues, while political takes also overshadowed other epistemological prospects, and vice versa. Repercussions have made inclusion of what is regarded as ‘inevitable changes’ within the built context problematic as to the re-interpretation and thus assessment of its authenticity. Despite their possible momentary threat to the latter, these changes may add to the cultural value of the context over time, granting new potential that may instead boost its authenticity. This paper investigates the potential continuity of Erbil Citadel’s Babylonian Gate as an inevitable change within the site’s built context by studying the Gate’s controversial political impacts on the context’s authenticity. This study affirms that authenticity is a transcendental value of an open-ended progressive nature, which cannot be reduced to a specific period or properties within the historical chronology of built heritage. Hence, authenticity should be approached as a meaningful existential issue, while revelation of its essence and thus its dimension entails precise scrutiny of both the tangibles and intangibles of the context. However, to be part of its authenticity, any change in the context should be adaptable and possibly incorporated as a new value within its cultural strata, thus enabling progressive support for site authenticity.


Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1324
Author(s):  
David Revell ◽  
Phil King ◽  
Jeff Giliam ◽  
Juliano Calil ◽  
Sarah Jenkins ◽  
...  

Sea level rise increases community risks from erosion, wave flooding, and tides. Current management typically protects existing development and infrastructure with coastal armoring. These practices ignore long-term impacts to public trust coastal recreation and natural ecosystems. This adaptation framework models physical responses to the public beach and private upland for each adaptation strategy over time, linking physical changes in widths to damages, economic costs, and benefits from beach recreation and nature using low-lying Imperial Beach, California, as a case study. Available coastal hazard models identified community vulnerabilities, and local risk communication engagement prioritized five adaptation approaches—armoring, nourishment, living shorelines, groins, and managed retreat. This framework innovates using replacement cost as a proxy for ecosystem services normally not valued and examines a managed retreat policy approach using a public buyout and rent-back option. Specific methods and economic values used in the analysis need more research and innovation, but the framework provides a scalable methodology to guide coastal adaptation planning everywhere. Case study results suggest that coastal armoring provides the least public benefits over time. Living shoreline approaches show greater public benefits, while managed retreat, implemented sooner, provides the best long-term adaptation strategy to protect community identity and public trust resources.


2021 ◽  
pp. 1-15
Author(s):  
Catarina Ianni Segatto ◽  
Mário Aquino Alves ◽  
Andrea Pineda

This article is a case study of Brazil, a country where Catholic-based organizations have historically played a key role in providing education and welfare services. Since the 1980s, these organizations have supported progressive changes at both the national and subnational levels. Nevertheless, the influence of religion on education policy has shifted in the last few decades. Pentecostal and Neopentecostal groups have gained prominence through representatives in the National Congress, and, in 2018, formed a coalition enabling the election of a right-wing populist President. We analyse the trajectory of religious groups’ influence on Brazil’s education policy over time (colonization to the 1980s, the 1980s to the beginning of the 2000s, and the 2000s until now) through a qualitative-historical analysis of primary and secondary data. This article argues that both Catholic and Protestant groups have influenced progressive changes in Brazil’s education policy, but they also share conservative ideas impeding further advances.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Ali Abdallah ◽  
Mohammed Abdel Rahem ◽  
Antonella Pasqualone

AbstractFood products suitable for Muslim consumers should be halal certified, particularly when their origins or production processes are doubtful. However, there is a multiplicity of halal standards. This situation may generate confusion, particularly for producers in Western countries who would like to certify their products in order to export them to Islamic countries. This study analyzed the reasons underlying the multiplicity of standards and reviewed the attempts of harmonization over time. Then, the case study of application to slaughterhouses was considered, by comparing four different halal standards (namely GSO 993:2015, OIC/SMIIC 1:2019, HAS 23103:2012, and MS 1500:2019) representative of different geographic areas. Animal stunning was critically examined, comparing tradition with modernity. The study evidenced that the basic requirements related to slaughtering are common to all the halal standards considered, but several differences occur in more specific details. Only a close collaboration between the authorities of all the countries involved in issuing halal certifications will lead to a homogeneous regulatory framework with unified certification and accreditation procedures, increasingly required in a globalized market.


Electronics ◽  
2021 ◽  
Vol 10 (14) ◽  
pp. 1714
Author(s):  
Mohamed Marey ◽  
Hala Mostafa

In this work, we propose a general framework to design a signal classification algorithm over time selective channels for wireless communications applications. We derive an upper bound on the maximum number of observation samples over which the channel response is an essential invariant. The proposed framework relies on dividing the received signal into blocks, and each of them has a length less than the mentioned bound. Then, these blocks are fed into a number of classifiers in a parallel fashion. A final decision is made through a well-designed combiner and detector. As a case study, we employ the proposed framework on a space-time block-code classification problem by developing two combiners and detectors. Monte Carlo simulations show that the proposed framework is capable of achieving excellent classification performance over time selective channels compared to the conventional algorithms.


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