| 21. |
- Andersson, Per-Johan, et al.
(författare)
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Power mapping and noise reduction for financial correlations
- 2005
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Ingår i: Acta Physica Polonica, Series B. - 0587-4254. ; 36:9, s. 2611-2619
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Konferensbidrag (refereegranskat)abstract
- The spectral properties of financial correlation matrices can show features known from completely random matrices. A major reason is noise originating from the finite lengths of the financial time series used to compute the correlation matrix elements. In recent years, various methods have been proposed to reduce this noise, i.e. to clean the correlation matrices. This is of direct practical relevance for risk management in portfolio optimization. In this contribution, we discuss in detail the power mapping, a new shrinkage method. We show that the relevant parameter is, to a certain extent, self-determined. Due to the "chirality" and the normalization of the correlation matrix, the optimal shrinkage parameter is fixed. We apply the power mapping and the well-known filtering method, to market data and compare them by optimizing stock portfolios. We address the rle of constraints by excluding short selling in the optimization.
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| 22. |
- Aramo-Immonen, Heli, 1964-, et al.
(författare)
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Charting the reach and contribution of IMP literature in other disciplines : A bibliometric analysis
- 2020
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Ingår i: Industrial Marketing Management. - : Elsevier. - 0019-8501 .- 1873-2062. ; 87, s. 47-62
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Tidskriftsartikel (refereegranskat)abstract
- The acknowledgement of a research tradition by other disciplines shows its contribution to the development of the broader body of scientific knowledge. This paper investigates the contribution of IMP (Industrial Marketing and Purchasing) research to broader research disciplines by analyzing how researchers within and beyond IMP have cited core IMP articles. First, through quantitative bibliometric analysis, the paper identifies the diffusion to other research disciplines. Thereafter, through qualitative analysis, the impact of the IMP perspective is captured to understand how strong these imprints are. The analyses show that IMP research has been noticed among a range of adjacent research disciplines. However, the use of IMP references has generally been rudimentary, and without a deeper understanding of the IMP ontology, meaning that IMP still has some “weak ties” to the other disciplines. Establishing IMP's contribution through enduring imprints would need further engagement with researchers from other research disciplines and publications in top journals. The paper contributes empirically with how the IMP perspective has spread beyond the IMP Group and theoretically by adding insight into how research ideas travel and transform to other disciplines.
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| 23. |
- Aramo-Immonen, Heli, 1964-, et al.
(författare)
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Clustering the IMP thought : Searching roots and diversities in IMP research
- 2018
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Ingår i: 34th Annual Industrial Marketing & Purchasing Conference KEDGE Business School, Marseille, France, 4-7 September 2018.
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Konferensbidrag (refereegranskat)abstract
- IMP research is often treated as an empirical perspective describing complexities of repeated business-to-business exchanges and their embeddedness. While building on some common understandings and concepts, this paper asks: How homogeneous is the IMP research? This paper uses cluster analysis to capture the roots and various sub-groups of IMP research as means to depict the question of homogeneity (i.e. a core focus in the research) or heterogeneity (i.e. using references from other fields or specific to sub-fields) of the IMP thought. In this scientific work in progress paper we introduce how we design to use bibliographical methods in order to harvest data from an extensive amount of IMP-related articles written from the 1970’s onwards. In this first attempt to reveal IMP we used overall 294 articles yielded to 10,615 co-citation relationships. A threshold of minimum number of citations of a cited reference was set to five (5) to capture such references that have been cited in multiple publications. We introduce visual mapping of defined subject area clusters and as an example we describe shortly clusters. Perhaps not surprisingly our findings suggest that IMP research is not so homogenous, with at least four clear clusters of IMP-research each utilizing different key referenfernces.
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| 24. |
- Arlinger, Stig, 1939-, et al.
(författare)
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Clinical trial of a digital hearing aid
- 1998
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Ingår i: Scandinavian Audiology. - : Taylor & Francis. - 0105-0397 .- 1940-2872. ; 27:1, s. 51-61
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Tidskriftsartikel (refereegranskat)abstract
- A clinical trial of Oticon DigiFocus hearing aid was performed. The test aid was evaluated on 33 subjects with several years' experience as users of modern analog hearing aids. These aids were used as reference for the 1-month-long trial. The Abbreviated Profile of Hearing Aid Benefit (APHAB) showed a mean difference in benefit with superior ratings for the test aid concerning ease of communication, speech in reverberation and speech in background noise. The subjects' own aids were rated somewhat better concerning aversiveness of sounds, but this difference was not statistically significant. The Gothenburg Profile showed a statistically significant difference between the test aid and the reference aids in favour of the test aid. The difference was not most evident with regard to speech communication and the effects of hearing loss on social interactions. Sound quality ratings concerning clearness were significantly higher for the test aid. Speech recognition thresholds in noise were on average 0.7 dB better for the test aids when tested at speech levels 60 and 75 dB. The difference was statistically significant only at 75 dB. There was significant interaction between general preference and hearing aid type, indicating that overall sound quality was an important factor affecting the general preference for either the test aid or the reference aid. Twenty-three subjects generally preferred the test aid, six preferred their own aid and four stated no difference.
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| 25. |
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ArtMonitor
- 2007
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Ingår i: ArtMonitor. - 1653-9958. ; :1
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Annan publikation (övrigt vetenskapligt/konstnärligt)
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| 26. |
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| 27. |
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| 28. |
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| 29. |
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| 30. |
- Berg, Kristina, et al.
(författare)
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Den goda resan : ett projekt som ska ge nya ideer och perspektiv på utveckling av turistmåltider
- 2000
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Den populärvetenskapliga publikationen "Den goda resan" handlar om turistmåltider i Sveriges inland. Skriften syftar till att ge nya idéer och perspektiv till den som vill utveckla sina turistmåltider och turistverksamheter. I boken förs en diskussion om turistmåltiden som fenomen och olika sätt att leverera måltider beroende på önskemål och situation. Ett historiskt och ett nutida perspektiv på hur mat och resande förhållit och förhåller sig till varandra är ett matnyttigt kapitel. Begrepp som lokala råvaror, regional identitet och balansen mellan det bekanta och det obekanta i turistmåltiden ges stort utrymme. Skriften avslutas med två exempel på hur man kan gå till väga när turistmåltider skapas. Det ena exemplet handlar om hur ett restaurangföretag kan utforma verksamheten, och det andra handlar om hur en turistföretagare kan skapa turistmåltider i nära relation till utomhusaktiviteter. Framför allt fokuseras turistföretagarnas syn på sin verksamhet och vilka problem de får brottas med. Författarna har rest från Gällivare till Hällefors vid olika tillfällen och studerat det måltidsutbud som turisterna idag har tillgång till. De har under sina resor också intervjuat producenter av turistmåltider, från dem som har idéer och handlingskraft att utveckla måltider till dem som inte vet vad de kan göra för att konstruera minnesvärda måltider för turister.
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