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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
411

Female Orgasm From Intercourse: Importance, Partner Characteristics, and Health

Powers, Catherine R. 08 1900 (has links)
Previous research indicates that women prefer orgasms triggered by penile-vaginal intercourse (PVI) as compared to those triggered by direct manual stimulation of the clitoris. However, for reasons that are not well understood, most women are unable to reach PVI orgasms as often as they desire. In addition, it is unclear why many women prefer PVI orgasms to those triggered by direct clitoral stimulation. This study developed a more precise measure of PVI orgasm frequency and evaluated key predictors of this frequency, including duration of intercourse, physical and psychological health, and partner traits with implications for either mating quality or relationship quality. The present study also measured PVI orgasm importance and investigated why it is important for many women. The sample consisted of 835 adult women with experience in PVI. Mean PVI orgasm frequency was 50%, with 39.4% of women never or rarely having PVI orgasms, 37.1% sometimes having PVI orgasms, and 23.5% almost always or always having PVI orgasms. As a median response, women believed that PVI orgasm was “very important” and perceived importance was correlated with orgasm frequency (r = .31, p < .001), as were reasons for importance. Duration of intercourse showed a linear relationship with PVI orgasm frequency, but this finding was qualified for women at the low and high extremes of the orgasm frequency distribution. Body esteem, anxiety during intercourse, exercise, and general pain predicted PVI orgasm frequency. Sensitive male traits, although valued by women even more highly than alpha male traits, showed notably weaker relationships with PVI orgasm than did male alpha traits. This is consistent with evolutionary theories of orgasm, and it supports the view that the female orgasm may function to favor some males over others in terms of sire choice. Clinical and theoretical implications of the present findings are discussed.
412

可轉換公司債存續期間之分析 / Anatomy of the convertible bond duration

陳嘉霖, Cheb, Chia-Lin Unknown Date (has links)
論文名稱:可轉換公司債存續期間之分析 校所組別:國立政治大學金融研究所 畢業時間:九十年度第二學期 提要別:碩士學位論文提要 研究生:陳嘉霖 指導教授:陳松男博士 論文提要及內容: 本研究在分析可轉債的存續期間,在存續期間的衡量上是採用有效存續期間法;而在可轉換公司債的評價上,假設股票價格服從幾何布朗寧運動,無風險利率的變動符合Hu1I-white利率模型,並且考量利率與股票報酬之間的相關性,建立可轉換公司債評價六元樹形圖。 本研究分別針對到期期限長短、價內外程度、股價波動度、利率波動度、股價與利率相關係數及票面利率等六項參數,作可轉換公司債存續期間的敏感度分析,研究結果為:1 加入贖回條款後,可轉債的存續期間高於未加任何條款下的可轉債存續期間。2 加入賣回條款後,可轉債的存續期間低於未加任何條款下的可轉債存續期間。3 加入贖回及賣回候款後,可轉債的存續期間會介於僅含贖回條款與僅含賣回條款的存續期間之中。4 距到期日愈長可轉債的存續期間愈高。5 愈價外的可轉債其存續期間愈高。6 股票波動度愈高,可轉債的存續期間愈低。7 利率波動度增加則可轉債的存續期間上升。8 股票價格與利率相關係數由正至負,可轉債的存續期間上升。9 若贖回權愈小,則票息上升會增加可轉債的存續期間。 關鍵字:可轉換公司債、存續期間、有效存續期間、六元樹、Hull-white、利率模型 / Title of Thesis: Anatomy of the Convertible Bond Duration Name of Institute: Graduate Institute of Money and Banking, NCCU Graduate Date: June, 2002 Name of Student: Chen, Chia-Lin Advisor: Dr. Chen, Son-Nan Abstract: This thesis uses effective duration method to anatomize the convertible bond duration. With the assumptions that stock price follows Geometric Brownian Motion and risk-free interest rate follows Hull and White model, we built a hexanomial tree to value the convertible bond. This thesis analyses the effects of the six parameters . They are maturity date, the ratio of the stock price versus the strike price, the correlation between stock return and interest rate, stock return volatility, interest rate volatility, and coupons. The conclusions include nine points. First, the value of convertible bond duration including call clauses is higher then pure convertible bond duration. Second, the value of convertible bond duration including put clauses is lower than pure convertible bond duration. Third, the value of convertible bond duration including both call and put clauses is between only including call or put clauses ones. Fourth, the longer the time to maturity is, the higher the convertible bond duration is. Fifth, the higher the ratio of the strike price versus the stock price is , the higher the convertible bond duration is. Sixth, the higher the stock volatility is , the lower the convertible bond duration is. Seventh, the higher the interest rate volatility is , the higher the convertible bond duration is. Eighth, the value of the correlation between stock return and interest rate increases from a negative value to a positive one, then the convertible bond duration increases. Ninth, if the value of call right is very small , the convertible bond duration will increase by the increasing of the coupon . Keywords: Convertible Bond, Duration, Effective Duration, Hexanomial Tree, Hull and White Interest Rate Model
413

Breastfeeding and introduction of other foods : A prospective longitudinal study in Sweden

Hörnell, Agneta January 2000 (has links)
<p>This study, based on daily recordings of infant feeding, comprised 506 infants from Uppsala, Sweden. All mothers had had previous breastfeeding experience of at least 4 months, and were planning to breastfeed the index child for ≥6 months.</p><p>Among exclusively breastfed infants there were wide variations in breastfeeding frequency and suckling duration per 24 hours both between infants and in the individual infant over time in the first 6 months. Most infants had an average of 1.0-2.9 feeds per night. Infants using a pacifier had fewer feeds and a shorter total suckling duration per 24 hours, and stopped breastfeeding earlier than infants not using a pacifier. These associations were not found for thumb sucking.</p><p>Accustoming the infants to solids was a lengthy process, the longer the younger the infant at introduction, and was associated with small changes in pattern and duration of breastfeeding. In contrast, formula was usually given in large amounts from the beginning, and when formula was given regularly the daily breastfeeding frequency and suckling duration declined swiftly. The younger an infant at the start of regular formula feeds, the shorter the breastfeeding duration. Occasional formula feeds did not affect the breastfeeding duration.</p><p>It is important for health personnel and parents to keep in mind that exclusively breastfed infants are not a homogeneous group, but rather members of distinct 'breastfeeding entities'. Moreover, if the aim is to introduce other foods 'under the protection of breast milk' it is important to realise that formula is also 'another food' and needs to be treated as such.</p>
414

Breastfeeding and introduction of other foods : A prospective longitudinal study in Sweden

Hörnell, Agneta January 2000 (has links)
This study, based on daily recordings of infant feeding, comprised 506 infants from Uppsala, Sweden. All mothers had had previous breastfeeding experience of at least 4 months, and were planning to breastfeed the index child for ≥6 months. Among exclusively breastfed infants there were wide variations in breastfeeding frequency and suckling duration per 24 hours both between infants and in the individual infant over time in the first 6 months. Most infants had an average of 1.0-2.9 feeds per night. Infants using a pacifier had fewer feeds and a shorter total suckling duration per 24 hours, and stopped breastfeeding earlier than infants not using a pacifier. These associations were not found for thumb sucking. Accustoming the infants to solids was a lengthy process, the longer the younger the infant at introduction, and was associated with small changes in pattern and duration of breastfeeding. In contrast, formula was usually given in large amounts from the beginning, and when formula was given regularly the daily breastfeeding frequency and suckling duration declined swiftly. The younger an infant at the start of regular formula feeds, the shorter the breastfeeding duration. Occasional formula feeds did not affect the breastfeeding duration. It is important for health personnel and parents to keep in mind that exclusively breastfed infants are not a homogeneous group, but rather members of distinct 'breastfeeding entities'. Moreover, if the aim is to introduce other foods 'under the protection of breast milk' it is important to realise that formula is also 'another food' and needs to be treated as such.
415

房地產仲介市場交易行為之研究

李春長 Unknown Date (has links)
近年來台灣房屋仲介市場可說發展的相當快速,許多賣方和買方常基於成本的考量,而透過仲介公司來買賣房屋。當然,委託給仲介公司來買賣房屋。其中可能主要因素即著眼於縮短交易的時間或者是提高成交的機率,本研究的整個重心將圍繞在賣方的訂價高低(底價)賣屋動機與房屋的屬性來解釋銷售期間和成交機率的高低,並且本文擬得用搜尋理論和代理人理論來詮釋房地產仲介市場的交易行為。 本研究主要分成六章,第一章為緒論。第二章從搜尋理論的觀點來研究訂價與成交價和銷售期間的關係。我們從賣方決定訂價之後,買方會依據訂價要求折扣率,而賣方也會決定一願意給買方的最小折扣率的角度出發,來建構房屋搜尋模型。由理論得知,賣方折扣率底線愈大,則預期銷售期間愈長;銷售期間愈長,則預期賣方折扣率底線愈低;搜尋成本愈大,則預期賣方折扣率底線愈小;買方要求折扣率分配的平均數愈大,則預期賣方折扣率底線愈大。在實證研究上,利用信義房屋仲介公司所提供的資料(1990-1993),以銷售期間和訂價相對於成交價的比例為應變數,採用聯立方程式的方式來估計分析。實證結果發現上述幾項論點皆獲得驗證與支持。 第三章模型同時考慮賣方和仲介業的行為,一方面說明賣方搜尋成本和買方所要求折扣率分配對銷售期間和成交機率的影響,另一方面提供未來修正理論模型的基礎。利用存活分析法(survival analysis)來估計銷售期間。一方面,我們要探究影響房屋交易之銷售期間的可能原因為何?另一方面,我們也想了解銷售期間是否具有時間相依性(time dependence),是否銷售期間越長者,越不易賣出?或越容易賣出? 第四章利用logit模型來估計房屋成交的機率,由於危險模型為純粹之計量模型,而非由理論模型所導出,所以分配之假設將限制其估計模型與理論的關連性,而logit模型則無此問題,因此本研究亦嘗試用logit模型來做估計。 第五章利用代理與搜尋模型來分析賣方和仲介業間的行為關係。不同的仲介收費制度--固定百分比收費(fixed-percentage commission)、定額制(flat-fee)、代銷(consignment sale),對雙方利益衝突的衝擊為何,是否潛藏著嚴重的道德危險(moral hazard)。透過本篇的分析,可瞭解何以固定百分比收費制度是台灣房屋仲介市場的收費趨勢。最後一章為結論與未來研究方向。 / This paper employs search theory to study the re1ationships between the list price, the transaction price,and marketing duration in the Taiwan real estate market. Theoretically, buyer uses the a set of criteria together,with the listing price to develop an offer which is based on a (guest) minimurn discount rate guideline form the listing price to determine a price that will be acceptable to the seller. We attempt to describe the impact of pricing strategies (seller's minimum discoun rate) and marketing duration by incorporating the minimurn discount rate in a search model. The derived search model indicates the presence of a positbive retalionship between the minimurn discount rate and marketing duration;an inverse relationship beteween marketing duration and munimurn discount rate; an inverse relationship between searching costs and mininurn discount rate; and a positive relationship between the buyer's average discount rate of distribution function and minimum discount rate. The study uses data collected during the l990-1993 time period and provided by Hsin Yi Realty Co., with the dependent variables being the marketing duration and the ratio of the listing price to the transaction price. A simultaneous equation is developed and used to analyze the following hypotheses: firstly, the higher the ratio of the listing price against the transaction price, the longer it takes to reach the marketing duraion; secondly, the longer it takes to reach the marketing duraion, the higher the ratio of the listing price against the transaction price; thirdly, the longer the period of consignment, the longer it takes to reach the marketing duration; and the fourth,if the seller is not in a hurry to sell,then the marketing duration becomes longer. Our empirical findings verify and support all the above stated analyses.
416

Custos de ajustamento e a dinâmica da estrutura de capital em empresas brasileiras

Machado, Guilherme Lelis Bernardo 26 May 2009 (has links)
Submitted by Guilherme Machado (guilhermelelis@hotmail.com) on 2009-07-19T00:38:21Z No. of bitstreams: 1 Dissertaçao MFEE Guilherme Machado.pdf: 462723 bytes, checksum: 37f59af1f922d119bd5b61eb3adeb553 (MD5) / Approved for entry into archive by Vitor Souza(vitor.souza@fgv.br) on 2009-07-20T14:10:37Z (GMT) No. of bitstreams: 1 Dissertaçao MFEE Guilherme Machado.pdf: 462723 bytes, checksum: 37f59af1f922d119bd5b61eb3adeb553 (MD5) / Made available in DSpace on 2009-07-20T14:11:08Z (GMT). No. of bitstreams: 1 Dissertaçao MFEE Guilherme Machado.pdf: 462723 bytes, checksum: 37f59af1f922d119bd5b61eb3adeb553 (MD5) / Several studies in Corporate Finance consider adjustment costs of companies’ capital structure irrelevant in its form and magnitude. This paper empirically examined adjustment costs influence on dynamic rebalancing behavior of capital structure of Brazilian listed companies from 1999 to 2007. Leverage ratios were presented under three different scenarios, considering fixed costs, proportional costs and a composition of fixed and proportional costs using a simulated reduced model of the capital structure. A non-parametric data analysis reveals that companies present a dynamic behavior in its financing decisions of capital structure adjustment, but that is far from continuous. A duration model proved to be the best choice to measure time between companies’ capital structure adjustments. Results are strongly relevant and support the theory of companies’ dynamic rebalancing behavior around an optimal range. However, adjustments do not occur immediately and the persistence shocks to capital structure accounts in its great part to adjustments costs instead of a possible indifference toward capital structure. This is a pioneer paper accounting for a djustment cost of capital structure in Brazilian market, which makes room for discussion around optimal capital structure on Brazilian companies. / Diversos estudos de Finanças Corporativas consideram os custos associados aos ajustes da estrutura de capital das empresas irrelevantes tanto na forma quanto em magnitude. Este estudo analisou empiricamente a influência dos custos de ajustamento na dinâmica dos ajustes da estrutura de capital de empresas brasileiras de capital aberto no período de 1999 a 2007. A alavancagem foi abordada sob três diferentes cenários, considerando a presença de custos fixos, custos proporcionais e por uma composição de custos fixos e proporcionais através de simulações utilizando um modelo reduzido da estrutura de capital. Em seguida a análise não paramétrica da amostra revelou que as empresas apresentam um comportamento dinâmico em suas decisões de financiamento para o ajuste da estruturas de capital, mas que não se revelou contínuo. A utilização de um modelo de duration mostrou-se adequado para mensurar o intervalo de tempo entre os ajustes da estrutura de capital das empresas. Os resultados são extremamente relevantes e suportam a teoria de um comportamento de rebalanceamento dinâmico pelas empresas de suas estruturas de capital em torno de um intervalo ótimo. Entretanto os ajustes não ocorrem de forma imediata e a persistência de choques à estrutura de capital deve-se em sua maior parte aos custos associados aos ajustes do que a uma possível indiferença à estrutura de capital. . Este trabalho constitui-se como pioneiro no mercado brasileiro acerca dos custos de ajustamento da estrutura de capital e abre espaço para a discussão do comportamento ótimo em torno da estrutura de capital de empresas nacionais.
417

[en] INTEREST RATE AS AN ADDITIONAL FACTOR TO EXPLAIN STOCKS RETURNS / [pt] JUROS COMO VARIÁVEL EXPLICATIVA PARA O RETORNO DE AÇÕES

CONRADO DE GODOY GARCIA 02 March 2018 (has links)
[pt] Este trabalho tem como objetivo explorar o benefício da inclusão de um novo fator relacionado a juros aos principais modelos de análise do cross-section dos retornos de ações, como o CAPM e o modelo de 3 fatores de Fama & French. O foco em especial é sobre a anomalia dos maiores retornos ajustados ao risco das estratégias de spread entre ações de baixo e alto beta de mercado, que também pode ser visto nos spreads entre ações de baixa e alta volatilidade. A motivação para inclusão deste fator vem da teoria de que o bom desempenho destas estratégias é simplesmente uma exposição a taxa de juros, não capturada pelos modelos usuais. Apesar da literatura apontar que as taxas de juros afetam diversas variáveis econômicas, a maior parte dos trabalhos de análise do cross-section dos retornos de ações é conduzida através de modelos de fatores compostos apenas por ações, sem fatores ou ativos diretamente relacionados a mudança da taxa de juros. A análise é feita com modelos lineares de fatores para o mercado acionário norte-americano entre 1976 até 2015. / [en] The literature shows that interest rates influence different economic variables such as consumption willingness, investment or expected asset returns. Notwithstanding, most works dealing with cross-sectional analysis of stock returns use only stock-based factor models disregarding the effects of interest rate movements. In this work, we explore the benefits of incrementing the traditional cross-sectional analysis (CAPM and Fama-French 3-factor model) with a new factor characterizing interest rate evolution over time. With this new factor, our model aims at better explaining stock return dispersion as well as a known anomaly of high risk-adjusted returns for low-volatility stock portfolios. Empirical analysis of linear factor models are carried out using US stock data using the Kenneth French database and the new factor is constructed using the US Aggregate do Barclays index that measures the return of low-risk assets.
418

Hétérogénéité dans des processus de développement cachés : inférence et analyse de populations structurées en environnements fluctuants / Heterogeneity in hidden developmental processes : inference and analysis for stage-structured populations in fluctuating environments

Castaño, Maria Soledad 12 April 2017 (has links)
Codakia orbicularis est un mollusque bivalve appartenant à la famille des Lucinidae et établissant des symbioses avec des bactéries sulfo-oxydantes (symbiotes) au sein de ses branchies. Dans l’hypothèse où toute symbiose nécessite une régulation par des molécules de dialogue, une étude chimique exhaustive pourrait aboutir à la mise en évidence des métabolites impliqués. Le travail de ce manuscrit porte donc sur l'isolement de métabolites secondaires à partir des branchies de ce bivalve et sur l'évaluation de l'activité antibactérienne des molécules isolées. Douze composés ont été isolés des branchies de Codakia orbicularis et leurs structures ont été déterminées par les méthodes spectroscopiques usuelles. Parmi ces molécules, une seule est nouvelle et a été nommée orbicularisine. Elle présente un squelette indolone spirotetracyclique inédit. Parmi les molécules isolées, seules quatre d’entre elles présentent une activité antibactérienne à savoir le soufre S8, la 4-hydroxybenzaldéhyde et deux monoglycérolipides. L'orbicularisine est inactive contre un panel de lignées cellulaires cancéreuses et de kinases. Le nouveau squelette de l’orbicularisine pourrait permettre d'aboutir à une nouvelle famille de molécules par synthèse organique et ainsi d'accroître la diversité moléculaire autour de ce motif inédit. Il sera également intéressant de déterminer l'origine des molécules isolées (procaryote ou eucaryote), particulièrement pour l’orbicularisine, et leurs rôles dans le cadre de la symbiose. Les résultats chimiques obtenus sur C. orbicularis et sur les Lucinidae en général sont intéressants puisque les espèces côtières appartenant aux bivalves ont été peu exploitées en chimie jusqu’à ce jour. / Codakia orbicularis is a bivalve mollusk belonging to the family Lucinidae harboring sulfur-oxidizing bacterial endosymbionts within its gills. Considering that any symbiosis is most likely regulated by dialogue molecules, an exhaustive chemical study could lead to identify the involved metabolites. Thus, the aim of this thesis focuses on the isolation of secondary metabolites from the gills of this bivalve and the evaluation of the antibacterial activity of the isolated molecules. Twelve compounds were isolated from the gills of Codakia orbicularis and their structures were determined by usual spectroscopic methods. Among these molecules, only one presented a new structure and has been named orbicularisine. The latter presents an undescribed spirotetracyclic indolone skeleton. Regarding the biological activities, among the isolated molecules, only four of them identified as S8 sulfur, 4-hydroxybenzaldehyde and two monoglycerolipids presented an antibacterial activity. Orbicularisine was inactive against a panel of cell lines and kinase. The orbicularisine new skeleton is an interesting start for the synthesis of new family of molecules, thus enhancing its molecular diversity. It will be interesting to determine the origin of the isolated molecules (prokaryotic or eukaryotic), especially for the new orbicularisine, and their roles in the frame of the symbiosis. The chemical results obtained on C. orbicularis and on lucinids in general are interesting since the coastal species belonging to Bivalves have not been chemically explored.
419

Die Bedeutung von Aufmerksamkeit für die Expositionsdauer im Mere Exposure Effect

Conrad, Samuel 11 November 2021 (has links)
Der wiederholte Kontakt mit einem neutralen Stimulus kann nach Zajonc (1968) zu einer Einstellungsverbesserung führen. Insbesondere die Häufigkeit der Exposition wurde intensiv untersucht und stellt eine zentrale Größe für den Mere Exposure Effect (MEE) dar. Uneindeutige Ergebnisse liegen dagegen für die Expositionsdauer vor (Bornstein, 1989). In einem Online-Experiment mit gemischtem Design (N=105) wurde der Einfluss der Gesamtdauer auf den MEE in Abhängigkeit von der Aufmerksamkeit untersucht. Die Aufmerksamkeitsmanipulation erfolgte im Sinne des Paradigmas von Betsch et al. (2010), durch eine Tastendruckbedingung, wodurch die Zeitverarbeitung gesteigert werden sollte. In den Ergebnissen zeigte sich kein Interaktionseffekt zwischen Gesamtdauer und Aufmerksamkeit. Außerdem konnte der Effekt des bloßen Kontakts nicht eindeutig identifiziert werden. Die höchste Anzahl sowie die längste Dauer der Exposition waren jedoch mit der stärksten Stimuluspräferenz assoziiert. Für die Aufmerksamkeit zeigte sich eine Einflusstendenz auf den untersuchten Effekt. Das Ergebnis einer Nebenhypothese deutet außerdem auf eine Bedeutung des Persönlichkeitsmerkmals Neurotizismus im MEE hin.:Zusammenfassung Abstract 1 Einleitung 2 Theorie 2.1 Mere Exposure Effect 2.1.1 Definition und Historie 2.1.2 Affective Primacy Model 2.1.3 Representation-Matching Model 2.1.4 Relevante Ergebnisse und Einflussfaktoren 2.2 Verarbeitung von Zeit und Häufigkeit 2.2.1 Definition und Merkmale 2.2.2 Relevante Forschungsergebnisse 2.3 Theoretische Ableitung der Hypothesen 3 Methodische Vorgehensweise 3.1 Rekrutierung und Stichprobe 3.2 Versuchsdesign 3.2.1 Unabhängige Variablen 3.2.2 Abhängige Variable 3.3 Material und Skalen 3.4 Umsetzung 3.5 Durchführung und Ablauf 3.6 Empirische Hypothesen 3.7 Auswertung und statistische Verfahren 3.8 Vorstudie 3.9 A-priori Poweranalyse 4 Ergebnisse 4.1 Deskriptive Statistik 4.2 Überprüfung der Aufmerksamkeitsmanipulation 4.3 Testung der Hypothesen 4.4 Zusätzliche Analysen 5 Diskussion 5.1 Interpretation der Ergebnisse 5.2 Einordnung der Ergebnisse 5.3 Limitationen und Probleme 5.4 Forschungsausblick 5.5 Fazit 6 Literaturverzeichnis Anhang / Repeated exposure to neutral stimuli is associated with an increase in preference (Zajonc, 1968). While the frequency of exposures is extensively researched and was found to be relevant in the mere exposure effect, the data for exposure duration is far from conclusive (Bornstein, 1989). In this study, a mixed design was used in an online-experiment (N=105) to investigate the relationship between total duration and stimulus preference depending on attentional variation. The manipulation of attention followed the paradigm of Betsch et al. (2010), in which pressing a key while the stimulus is being presented increased attention and therefore temporal processing. The results showed no interaction between total duration of exposure and attention. Moreover, there was no correlational effect of mere exposure found in this study. But both the most frequent exposure as well as the longest total duration condition where associated with the highest affective rating. In the absence of statistical significance, attention was related to the MEE. The testing of a secondary hypothesis revealed a possible importance of neuroticism in the liking of familiar versus unfamiliar stimuli.:Zusammenfassung Abstract 1 Einleitung 2 Theorie 2.1 Mere Exposure Effect 2.1.1 Definition und Historie 2.1.2 Affective Primacy Model 2.1.3 Representation-Matching Model 2.1.4 Relevante Ergebnisse und Einflussfaktoren 2.2 Verarbeitung von Zeit und Häufigkeit 2.2.1 Definition und Merkmale 2.2.2 Relevante Forschungsergebnisse 2.3 Theoretische Ableitung der Hypothesen 3 Methodische Vorgehensweise 3.1 Rekrutierung und Stichprobe 3.2 Versuchsdesign 3.2.1 Unabhängige Variablen 3.2.2 Abhängige Variable 3.3 Material und Skalen 3.4 Umsetzung 3.5 Durchführung und Ablauf 3.6 Empirische Hypothesen 3.7 Auswertung und statistische Verfahren 3.8 Vorstudie 3.9 A-priori Poweranalyse 4 Ergebnisse 4.1 Deskriptive Statistik 4.2 Überprüfung der Aufmerksamkeitsmanipulation 4.3 Testung der Hypothesen 4.4 Zusätzliche Analysen 5 Diskussion 5.1 Interpretation der Ergebnisse 5.2 Einordnung der Ergebnisse 5.3 Limitationen und Probleme 5.4 Forschungsausblick 5.5 Fazit 6 Literaturverzeichnis Anhang
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Analysis of Potential Determinants of Cycle Commuting Speed : With Special Reference to Gears, Showers, and Ratings of Perceived Exertion

Cunelius, Erik January 2020 (has links)
Aim: The aim of this study is to analyse potential determinants of cycle commuting speed, with the following research questions: 1. How does cycle commuting speed relate to amount of gears, access to shower facilities, and rating of perceived exertion (RPE), when sex, age, weight, body mass index (BMI), duration, last digit in self-reported duration, and cycling area are controlled for? 2. How are the earlier found relationships between speed and duration, and speed and sex, affected when amount of gears, access to shower facilities, and RPE are added to the control variables age, weight, BMI, last digit in self-reported duration, and cycling area?   Method: In this cross-sectional study, 1526 adult cycle commuters (67% females) in Stockholm County, Sweden, were recruited through advertisements. In a self-administered questionnaire, the respondents reported their sex, age, height, weight, duration of their typical cycle commuting journey, amount of gears, access to shower facilities at the destination, and rating of perceived exertion (measured by the Borg RPE Scale) while cycling. They also drew their cycling route on an individually adjusted map. Multiple linear regression was used to facilitate the analyses.   Results: In a regression model with the independent variables sex, age, weight, body mass index, duration, last digit in self-reported duration (1–4 or 6–9 compared to 0 or 5), cycling area (inner urban compared to suburban and suburban – inner urban), gears, shower facilities, and RPE, the dependent variable cycle commuting speed was positively related to using a bicycle with five or more (as compared to four or fewer) gears, having convenient (as opposed to inconvenient or non-existent) access to shower facilities, and perceiving a higher degree of exertion while cycling. Gears, showers, and RPE were also found to substantially affect the earlier found relationships between speed and duration, and speed and sex. The respondents showed a clear tendency of giving odd-numbered, compared to even-numbered, ratings of perceived exertion.   Conclusions: This study highlights the importance of gears, showers, and RPE in activities such as estimating, planning or taking measures in relation to cycle commuting. It also shows that adding new factors to control for might change earlier established relationships within this field. When the Borg RPE Scale is used, correct instructions strengthens the validity. / Syfte och frågeställningar: Syftet med denna studie är att analysera potentiella påverkansfaktorer gällande cykelpendlingshastighet, med följande frågeställningar: 1. Hur relaterar hastighet till antal växlar, tillgång till duschfaciliteter och skattning av egenupplevd fysisk ansträngningsgrad (RPE), när kön, ålder, vikt, BMI, duration, slutsiffra i självrapporterad duration samt cykelområde kontrolleras? 2. Hur påverkas de tidigare funna förhållandena mellan hastighet och duration, samt hastighet och kön, när antal växlar, tillgång till duschfaciliteter och RPE adderas till kontrollvariablerna ålder, vikt, BMI, slutsiffra i självrapporterad duration, och cykelområde?   Metod: I denna tvärsnittsstudie rekryterades 1526 vuxna cykelpendlare (67% kvinnor) i Stockholms län genom annonser. I ett själv-administrerat formulär rapporterade de kön, ålder, längd, vikt, duration vid deras typiska cykelpendlingsresa, antal växlar, tillgång till duschfaciliteter vid destinationen, och skattning av egenupplevd fysisk ansträngningsgrad (enligt Borgskalan) under cyklingen. De ritade även in sin cykelväg på en individuellt anpassad karta. Multipel linjär regression användes för att möjliggöra analyserna.   Resultat: I en regressionsmodell med de oberoende variablerna kön, ålder, vikt, BMI, duration, slutsiffra i självrapporterad duration (1­–4 eller 6–9 jämfört med 0 eller 5), cykelområde (innerstad i jämförelse med ytterstad samt ytterstad – innerstad), växlar, duschmöjligheter och RPE, var den beroende variabeln cykelhastighet positivt relaterad till användandet av en cykel med fem växlar eller fler (i jämförelse med fyra eller färre), att ha bekväm tillgång till dusch (i motsats till obekväm eller ingen tillgång alls) samt att uppleva en högre grad av fysisk ansträngning under cykling. Växlar, duschmöjligheter och RPE visade sig även substantiellt påverka de tidigare funna förhållandena mellan hastighet och duration, samt hastighet och kön. Respondenterna visade en tydlig tendens att ge ojämna, i jämförelse med jämna, RPE-skattningar.   Slutsats: Denna studie belyser vikten av växlar, duschmöjligheter och egenupplevd ansträngningsgrad vid exempelvis bedömning, planering eller vidtagande av åtgärder i relation till cykelpendling. Den visar även att nya kontrollfaktorer kan förändra tidigare etablerade förhållanden inom detta fält. Korrekta instruktioner stärker validiteten vid användandet av Borgskalan.

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