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406 results on '"Virolainen, P"'

1. The COSMOS-Web deep galaxy group catalog up to $z=3.7$

Author

Toni, Greta, Gozaliasl, Ghassem, Maturi, Matteo, Moscardini, Lauro, Finoguenov, Alexis, Castignani, Gianluca, Gentile, Fabrizio, Virolainen, Kaija, Casey, Caitlin M., Kartaltepe, Jeyhan S., Akins, Hollis B., Allen, Natalie, Arango-Toro, Rafael C., Babul, Arif, Brinch, Malte, Drakos, Nicole E., Faisst, Andreas L., Franco, Maximilien, Griffiths, Richard E., Harish, Santosh, Hasinger, Günther, Ilbert, Olivier, Jin, Shuowen, Khostovan, Ali Ahmad, Koekemoer, Anton M., Korpi-Lagg, Maarit, Larson, Rebecca L., Lertprasertpong, Jitrapon, Liu, Daizhong, Magdis, Georgios, Massey, Richard, McCracken, Henry J., McKinney, Jed, Paquereau, Louise, Rhodes, Jason, Robertson, Brant E., Sargent, Mark, Shuntov, Marko, Tanaka, Masayuki, Taamoli, Sina, Tempel, Elmo, Toft, Sune, Vardoulaki, Eleni, and Yang, Lilan

Subjects
Astrophysics - Astrophysics of Galaxies, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Galaxy groups with $M_{tot} \lesssim 10^{14}$ $M_\odot$ and up to a few tens of members are the most common galaxy environment, marking the transition between field and massive clusters. Identifying groups plays a crucial role in understanding structure formation and galaxy evolution. Modern deep surveys allow us to build well-characterized samples of groups up to the regime where structures were taking shape. We aimed to build the largest deep catalog of galaxy groups to date over the COSMOS-Web field effective area of 0.45 deg$^2$, leveraging the deep high quality data of the new COSMOS-Web photometric catalog resulted from the James Webb Space Telescope observations of the COSMOS-Web field. We performed the group search with the AMICO algorithm, a linear matched filter based on an analytical model for the group signal. AMICO has already been tested in wide and deep field surveys, including COSMOS data up to $z=2$. In this work, we tested the algorithm performances at even higher redshift and searched for protocluster cores at $z>2$. We compiled a list of known protoclusters in COSMOS at $2 \leq z \leq 3.7$, matched them with our detections and studied the clustering of the detected cores. We estimated purity and completeness of our sample by creating data-driven mocks with the SinFoniA code and linked signal-to-noise to purity. We detected 1678 groups in the COSMOS-Web field up to $z=3.7$, including lists of members extending nearly two magnitudes deeper than the previous AMICO-COSMOS catalog. 756 groups were detected with purity of 80\%. More than 500 groups have their redshift confirmed by assigning spectroscopic counterparts. This group catalog offers a unique opportunity to explore galaxy evolution in different environments spanning $\sim$12 Gyr and to study groups, from the least rich population to the formation of the most massive clusters., Comment: 17 pages, 14 figures, 2 tables (including appendices), submitted to Astronomy & Astrophysics (A&A)

Published
2025

2. Retention of Newcomers and Factors Influencing Turnover Intentions and Behaviour: A Review of the Literature

Author

Niels Andreas van der Baan, Giulia Meinke, Maarit Hannele Virolainen, Simon Beausaert, and Inken Gast

Abstract

Purpose: Recent graduates are an important source of talent among hired employees as they bring up-to-date knowledge into the organisation. Yet, organisations have difficulties retaining them and recognizing factors influencing their voluntary turnover, which may differ from those influencing voluntary turnover among tenured employees. For example, graduate employees need to adjust to a completely new context and develop their identity as professionals. Therefore, the current study presents a review of the factors influencing newcomers' voluntary turnover and turnover intentions. Design/methodology/approach: To explore the factors influencing the turnover intentions and behaviour of recently hired employees, we conducted a literature review of 57 articles from several databases for different disciplines. Findings: Our review identifies factors that influence turnover intentions and behaviour among recently hired employees and presents them in a model. The model identifies five categories of factors influencing turnover intentions and behaviour: pre-joining expectations, person-environment fit, the role of the supervisor, human resource (HR) practices and person-related factors. Practical implications: The model enhances the understanding of why new employees leave an organisation and shows how supervisors and HR practices play an important role in reducing voluntary turnover among newly hired employees. The article concludes with practical suggestions on how to retain these employees. Originality/value: While employee turnover has been studied extensively, this review focuses specifically on factors that influence the turnover intentions and behaviour of newcomers. We present these factors in a model that can be used to inform managerial practices to reduce turnover among newcomers.

Published
2025
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3. Identification by non-Gaussianity in structural threshold and smooth transition vector autoregressive models

Author

Virolainen, Savi

Subjects
Economics - Econometrics, Mathematics - Statistics Theory, Statistics - Methodology, 62M10
Abstract

Linear structural vector autoregressive models can be identified statistically without imposing restrictions on the model if the shocks are mutually independent and at most one of them is Gaussian. We show that this result extends to structural threshold and smooth transition vector autoregressive models incorporating a time-varying impact matrix defined as a weighted sum of the impact matrices of the regimes. We also discuss the problem of labelling the shocks, estimation of the parameters, and stationarity the model. The introduced methods are implemented to the accompanying R package sstvars. Our empirical application studies the effects of the climate policy uncertainty shock on the U.S. macroeconomy. In a structural logistic smooth transition vector autoregressive model consisting of two regimes, we find that a positive climate policy uncertainty shock decreases production and increases inflation in times of both low and high economic policy uncertainty, but its inflationary effects are stronger in the periods of high economic policy uncertainty.

Published
2024

7. A Gaussian smooth transition vector autoregressive model: An application to the macroeconomic effects of severe weather shocks

Author

Lanne, Markku and Virolainen, Savi

Subjects
Economics - Econometrics, 62M10, G.3
Abstract

We introduce a new smooth transition vector autoregressive model with a Gaussian conditional distribution and transition weights that, for a $p$th order model, depend on the full distribution of the preceding $p$ observations. Specifically, the transition weight of each regime increases in its relative weighted likelihood. This data-driven approach facilitates capturing complex switching dynamics, enhancing the identification of gradual regime shifts. In an empirical application to the macroeconomic effects of a severe weather shock, we find that in monthly U.S. data from 1961:1 to 2022:3, the shock has stronger impact in the regime prevailing in the early part of the sample and in certain crisis periods than in the regime dominating the latter part of the sample. This suggests overall adaptation of the U.S. economy to severe weather over time.

Published
2024

12. Gaussian and Student's $t$ mixture vector autoregressive model with application to the effects of the Euro area monetary policy shock

Author

Virolainen, Savi

Subjects
Economics - Econometrics, Statistics - Methodology, 62M10
Abstract

A new mixture vector autoregressive model based on Gaussian and Student's $t$ distributions is introduced. As its mixture components, our model incorporates conditionally homoskedastic linear Gaussian vector autoregressions and conditionally heteroskedastic linear Student's $t$ vector autoregressions. For a $p$th order model, the mixing weights depend on the full distribution of the preceding $p$ observations, which leads to attractive practical and theoretical properties such as ergodicity and full knowledge of the stationary distribution of $p+1$ consecutive observations. A structural version of the model with statistically identified shocks is also proposed. The empirical application studies the effects of the Euro area monetary policy shock. We fit a two-regime model to the data and find the effects, particularly on inflation, stronger in the regime that mainly prevails before the Financial crisis than in the regime that mainly dominates after it. The introduced methods are implemented in the accompanying R package gmvarkit., Comment: arXiv admin note: text overlap with arXiv:2007.04713

Published
2021

14. Structural Gaussian mixture vector autoregressive model with application to the asymmetric effects of monetary policy shocks

Author

Virolainen, Savi

Subjects
Economics - Econometrics, Statistics - Methodology, 62M10
Abstract

A structural Gaussian mixture vector autoregressive model is introduced. The shocks are identified by combining simultaneous diagonalization of the reduced form error covariance matrices with constraints on the time-varying impact matrix. This leads to flexible identification conditions, and some of the constraints are also testable. The empirical application studies asymmetries in the effects of the U.S. monetary policy shock and finds strong asymmetries with respect to the sign and size of the shock and to the initial state of the economy. The accompanying CRAN distributed R package gmvarkit provides a comprehensive set of tools for numerical analysis.

Published
2020

17. A mixture autoregressive model based on Gaussian and Student's $t$-distributions

Author

Virolainen, Savi

Subjects
Economics - Econometrics, Mathematics - Statistics Theory, Statistics - Methodology, 62M10
Abstract

We introduce a new mixture autoregressive model which combines Gaussian and Student's $t$ mixture components. The model has very attractive properties analogous to the Gaussian and Student's $t$ mixture autoregressive models, but it is more flexible as it enables to model series which consist of both conditionally homoscedastic Gaussian regimes and conditionally heteroscedastic Student's $t$ regimes. The usefulness of our model is demonstrated in an empirical application to the monthly U.S. interest rate spread between the 3-month Treasury bill rate and the effective federal funds rate.

Published
2020

21. FinnGen provides genetic insights from a well-phenotyped isolated population

Author

Kurki, Mitja I., Karjalainen, Juha, Palta, Priit, Sipilä, Timo P., Kristiansson, Kati, Donner, Kati M., Reeve, Mary P., Laivuori, Hannele, Aavikko, Mervi, Kaunisto, Mari A., Loukola, Anu, Lahtela, Elisa, Mattsson, Hannele, Laiho, Päivi, Della Briotta Parolo, Pietro, Lehisto, Arto A., Kanai, Masahiro, Mars, Nina, Rämö, Joel, Kiiskinen, Tuomo, Heyne, Henrike O., Veerapen, Kumar, Rüeger, Sina, Lemmelä, Susanna, Zhou, Wei, Ruotsalainen, Sanni, Pärn, Kalle, Hiekkalinna, Tero, Koskelainen, Sami, Paajanen, Teemu, Llorens, Vincent, Gracia-Tabuenca, Javier, Siirtola, Harri, Reis, Kadri, Elnahas, Abdelrahman G., Sun, Benjamin, Foley, Christopher N., Aalto-Setälä, Katriina, Alasoo, Kaur, Arvas, Mikko, Auro, Kirsi, Biswas, Shameek, Bizaki-Vallaskangas, Argyro, Carpen, Olli, Chen, Chia-Yen, Dada, Oluwaseun A., Ding, Zhihao, Ehm, Margaret G., Eklund, Kari, Färkkilä, Martti, Finucane, Hilary, Ganna, Andrea, Ghazal, Awaisa, Graham, Robert R., Green, Eric M., Hakanen, Antti, Hautalahti, Marco, Hedman, Åsa K., Hiltunen, Mikko, Hinttala, Reetta, Hovatta, Iiris, Hu, Xinli, Huertas-Vazquez, Adriana, Huilaja, Laura, Hunkapiller, Julie, Jacob, Howard, Jensen, Jan-Nygaard, Joensuu, Heikki, John, Sally, Julkunen, Valtteri, Jung, Marc, Junttila, Juhani, Kaarniranta, Kai, Kähönen, Mika, Kajanne, Risto, Kallio, Lila, Kälviäinen, Reetta, Kaprio, Jaakko, Kerimov, Nurlan, Kettunen, Johannes, Kilpeläinen, Elina, Kilpi, Terhi, Klinger, Katherine, Kosma, Veli-Matti, Kuopio, Teijo, Kurra, Venla, Laisk, Triin, Laukkanen, Jari, Lawless, Nathan, Liu, Aoxing, Longerich, Simonne, Mägi, Reedik, Mäkelä, Johanna, Mäkitie, Antti, Malarstig, Anders, Mannermaa, Arto, Maranville, Joseph, Matakidou, Athena, Meretoja, Tuomo, Mozaffari, Sahar V., Niemi, Mari E. K., Niemi, Marianna, Niiranen, Teemu, O´Donnell, Christopher J., Obeidat, Ma´en, Okafo, George, Ollila, Hanna M., Palomäki, Antti, Palotie, Tuula, Partanen, Jukka, Paul, Dirk S., Pelkonen, Margit, Pendergrass, Rion K., Petrovski, Slavé, Pitkäranta, Anne, Platt, Adam, Pulford, David, Punkka, Eero, Pussinen, Pirkko, Raghavan, Neha, Rahimov, Fedik, Rajpal, Deepak, Renaud, Nicole A., Riley-Gillis, Bridget, Rodosthenous, Rodosthenis, Saarentaus, Elmo, Salminen, Aino, Salminen, Eveliina, Salomaa, Veikko, Schleutker, Johanna, Serpi, Raisa, Shen, Huei-yi, Siegel, Richard, Silander, Kaisa, Siltanen, Sanna, Soini, Sirpa, Soininen, Hilkka, Sul, Jae Hoon, Tachmazidou, Ioanna, Tasanen, Kaisa, Tienari, Pentti, Toppila-Salmi, Sanna, Tukiainen, Taru, Tuomi, Tiinamaija, Turunen, Joni A., Ulirsch, Jacob C., Vaura, Felix, Virolainen, Petri, Waring, Jeffrey, Waterworth, Dawn, Yang, Robert, Nelis, Mari, Reigo, Anu, Metspalu, Andres, Milani, Lili, Esko, Tõnu, Fox, Caroline, Havulinna, Aki S., Perola, Markus, Ripatti, Samuli, Jalanko, Anu, Laitinen, Tarja, Mäkelä, Tomi P., Plenge, Robert, McCarthy, Mark, Runz, Heiko, Daly, Mark J., and Palotie, Aarno

Published
2023
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26. Balancing 'Flexibility' and 'Employability': The Changing Role of General Studies in The Finnish and Swedish VET Curricula of the 1990s and 2010s

Author

Nylund, Mattias and Virolainen, Maarit

Abstract

This article analyses and compares the evolving role of general subjects in the curricula of initial upper secondary vocational education and training (VET) in Finland and Sweden during the 1990s and 2010s. The research illustrates how Bernstein's concept of 'pedagogic code' supports comparative studies on principles guiding changes to curricula and how the role of general studies in VET has been redefined. The findings show that while a principle of 'market relevance' has been central to VET over the decades since the 1990s, it has been subject to varying interpretations. The shifts in interpretations have guided the organisation of VET in these two countries in different directions, including the role of general subjects within the curriculum. On a general level, the countries share some key similarities. Both countries emphasised lifelong learning and a broadening of VET in the 1990s, based on a core principle of 'flexibility'. In the 2010s, the earlier promotion of flexibility and universal access to higher education was superseded by a stronger focus on employability and entrepreneurship in addition to students' command of more specific vocational tasks.

Published
2019
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27. Finnish Vocational Education and Training in Comparison: Strengths and Weaknesses

Author

Virolainen, Maarit and Stenström, Marja-Leena

Abstract

The study investigates how the Finnish model of providing initial vocational education and training (IVET) has succeeded in terms of enhancing educational progress and employability. A relatively high level of participation in IVET makes the Finnish model distinctive from those of three other Nordic countries: Denmark, Norway and Sweden. All four Nordic countries have well-organised labour markets and universal types of welfare states. Priority is given to goals related to equal opportunities and social inclusion. At the same time, these countries have different models of IVET. While the study compares the Finnish model of organising IVET to those of other Nordic countries, it also examines the German and UK models, which represent differing societal approaches to IVET. The differences in the outcomes of the IVET systems are described and analysed through reviewing secondary data provided by Eurydice and Eurostat, along with country reports produced in a Nordic comparative project, Nord-VET.

Published
2014

28. Author Correction: FinnGen provides genetic insights from a well-phenotyped isolated population

Author

Kurki, Mitja I., Karjalainen, Juha, Palta, Priit, Sipilä, Timo P., Kristiansson, Kati, Donner, Kati M., Reeve, Mary P., Laivuori, Hannele, Aavikko, Mervi, Kaunisto, Mari A., Loukola, Anu, Lahtela, Elisa, Mattsson, Hannele, Laiho, Päivi, Della Briotta Parolo, Pietro, Lehisto, Arto A., Kanai, Masahiro, Mars, Nina, Rämö, Joel, Kiiskinen, Tuomo, Heyne, Henrike O., Veerapen, Kumar, Rüeger, Sina, Lemmelä, Susanna, Zhou, Wei, Ruotsalainen, Sanni, Pärn, Kalle, Hiekkalinna, Tero, Koskelainen, Sami, Paajanen, Teemu, Llorens, Vincent, Gracia-Tabuenca, Javier, Siirtola, Harri, Reis, Kadri, Elnahas, Abdelrahman G., Sun, Benjamin, Foley, Christopher N., Aalto-Setälä, Katriina, Alasoo, Kaur, Arvas, Mikko, Auro, Kirsi, Biswas, Shameek, Bizaki-Vallaskangas, Argyro, Carpen, Olli, Chen, Chia-Yen, Dada, Oluwaseun A., Ding, Zhihao, Ehm, Margaret G., Eklund, Kari, Färkkilä, Martti, Finucane, Hilary, Ganna, Andrea, Ghazal, Awaisa, Graham, Robert R., Green, Eric M., Hakanen, Antti, Hautalahti, Marco, Hedman, Åsa K., Hiltunen, Mikko, Hinttala, Reetta, Hovatta, Iiris, Hu, Xinli, Huertas-Vazquez, Adriana, Huilaja, Laura, Hunkapiller, Julie, Jacob, Howard, Jensen, Jan-Nygaard, Joensuu, Heikki, John, Sally, Julkunen, Valtteri, Jung, Marc, Junttila, Juhani, Kaarniranta, Kai, Kähönen, Mika, Kajanne, Risto, Kallio, Lila, Kälviäinen, Reetta, Kaprio, Jaakko, Kerimov, Nurlan, Kettunen, Johannes, Kilpeläinen, Elina, Kilpi, Terhi, Klinger, Katherine, Kosma, Veli-Matti, Kuopio, Teijo, Kurra, Venla, Laisk, Triin, Laukkanen, Jari, Lawless, Nathan, Liu, Aoxing, Longerich, Simonne, Mägi, Reedik, Mäkelä, Johanna, Mäkitie, Antti, Malarstig, Anders, Mannermaa, Arto, Maranville, Joseph, Matakidou, Athena, Meretoja, Tuomo, Mozaffari, Sahar V., Niemi, Mari E. K., Niemi, Marianna, Niiranen, Teemu, O´Donnell, Christopher J., Obeidat, Ma´en, Okafo, George, Ollila, Hanna M., Palomäki, Antti, Palotie, Tuula, Partanen, Jukka, Paul, Dirk S., Pelkonen, Margit, Pendergrass, Rion K., Petrovski, Slavé, Pitkäranta, Anne, Platt, Adam, Pulford, David, Punkka, Eero, Pussinen, Pirkko, Raghavan, Neha, Rahimov, Fedik, Rajpal, Deepak, Renaud, Nicole A., Riley-Gillis, Bridget, Rodosthenous, Rodosthenis, Saarentaus, Elmo, Salminen, Aino, Salminen, Eveliina, Salomaa, Veikko, Schleutker, Johanna, Serpi, Raisa, Shen, Huei-yi, Siegel, Richard, Silander, Kaisa, Siltanen, Sanna, Soini, Sirpa, Soininen, Hilkka, Sul, Jae Hoon, Tachmazidou, Ioanna, Tasanen, Kaisa, Tienari, Pentti, Toppila-Salmi, Sanna, Tukiainen, Taru, Tuomi, Tiinamaija, Turunen, Joni A., Ulirsch, Jacob C., Vaura, Felix, Virolainen, Petri, Waring, Jeffrey, Waterworth, Dawn, Yang, Robert, Nelis, Mari, Reigo, Anu, Metspalu, Andres, Milani, Lili, Esko, Tõnu, Fox, Caroline, Havulinna, Aki S., Perola, Markus, Ripatti, Samuli, Jalanko, Anu, Laitinen, Tarja, Mäkelä, Tomi P., Plenge, Robert, McCarthy, Mark, Runz, Heiko, Daly, Mark J., and Palotie, Aarno

Published
2023
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44. Varieties of Universalism: Post-1990s Developments in the Initial School-Based Model of VET in Finland and Sweden and Implications for Transitions to the World of Work and Higher Education

Author

Virolainen, M. and Persson Thunqvist, D.

Abstract

The Nordic countries are often referred to as a group even though their education systems and training models are very different. The aim of this study is to advance understanding of those differences and compare the developments and organisation of initial vocational education and training (IVET) in Finland and Sweden since the 1990s as examples of school-based models of IVET in statist regimes. The research questions address the following: how these two countries have institutionalised school-based IVET since the 1990s; the kinds of legislative reforms that have been decisive for the construction of school-based IVET; and how the models of school-based IVET in these two countries allow access to higher education and the world of work. The analysis shows the heterogeneity of the statist model of school-based IVET systems in two Nordic countries and underlines differences with respect to school-to-work transitions between IVET and different labour market sectors.

Published
2017
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