Topics in Spatial Econometrics - With Applications to House Prices

Topics in Spatial Econometrics — With Applications to House Prices Spatial effects in data occur when geographical closeness of observations influences the relation between the observations. When two points on a map are close to each other, the observed values on a variable at those points tend to be similar. The further away the two points are from each other, the less similar the observed values tend to be. Recent technical developments, geographical information systems (GIS) and global positioning systems (GPS) have brought about a renewed interest in spatial matters. For instance, it is possible to observe the exact location of an observation and combine it with other characteristics. Spatial econometrics integrates spatial aspects into econometric models and analysis. The thesis concentrates mainly on methodological issues, but the findings are illustrated by empirical studies on house price data. The thesis consists of an introductory chapter and four essays. The introductory chapter presents an overview of topics and problems in spatial econometrics. It discusses spatial effects, spatial weights matrices, especially k-nearest neighbours weights matrices, and various spatial econometric models, as well as estimation methods and inference. Further, the problem of omitted variables, a few computational and empirical aspects, the bootstrap procedure and the spatial J-test are presented. In addition, a discussion on hedonic house price models is included. In the first essay a comparison is made between spatial econometrics and time series analysis. By restricting the attention to unilateral spatial autoregressive processes, it is shown that a unilateral spatial autoregression, which enjoys similar properties as an autoregression with time series, can be defined. By an empirical study on house price data the second essay shows that it is possible to form coordinate-based, spatially autoregressive variables, which are at least to some extent able to replace the spatial structure in a spatial econometric model. In the third essay a strategy for specifying a k-nearest neighbours weights matrix by applying the spatial J-test is suggested, studied and demonstrated. In the final fourth essay the properties of the asymptotic spatial J-test are further examined. A simulation study shows that the spatial J-test can be used for distinguishing between general spatial models with different k-nearest neighbours weights matrices. A bootstrap spatial J-test is suggested to correct the size of the asymptotic test in small samples.

Only Connect?: Aspects of Intertextuality in Zadie Smith's On Beauty

Tutkielma käsittelee intertekstuaalisuuden eri muotoja Zadie Smithin romaanissa On Beauty (suom. Kauneudesta). Tutkimuksen tarkoitus on osoittaa kuinka oleellisesti intertekstuaalisuuden teoria on vaikuttanut kirjallisuustieteen metodeihin ja postmoderniin kirjallisuuskäsitykseen, sekä käsitellä sen soveltuvuutta nykykirjallisuuden tutkimiseen analysoimalla teorian sisäistä monimuotoisuutta ja ristiriitoja. Tutkimusmateriaalina käytetään Smithin romaanin lisäksi E. M. Forsterin romaania Howards End (suom. Talo jalavan varjossa), johon On Beauty tietoisesti viittaa. Teoreettisena viitekehyksenä tutkielmassa toimii Gérard Genetten teoksessa Palimpsests sekä Roland Barthesin esseessä Tekijän kuolema esille tuodut kirjallisuusteoreettiset käsitykset. Valittu metodologia antaa mahdollisuuden hahmottaa intertekstuaalisuus kahdella eri tavalla: Genetten strukturalistinen lähestymistapa soveltuu teosten välisten viittaussuhteiden tutkimiseen, kun taas Barthesin jälkistrukturalistinen diskurssi auttaa ymmärtämään tekstienvälisyyden osana merkityksen jatkuvaa epävakautta. Tutkielman ensimmäinen osio keskittyy analysoimaan lähiluvun keinoin romaanien On Beauty ja Howards End välistä strukturalistista suhdetta vertailemalla teosten eroja ja yhtäläisyyksiä Genetten intertekstuaalisuusteorian valossa. Vertailussa kiinnetetään erityisesti huomiota teosten juoneen, rakenteeseen, aikaan ja paikkaan, sekä uudelleenkirjoitusten yleiseen tendenssiin päivittää alkuperäistä tarinaa kohdeyleisölle paremmin sopivaksi. Toisessa osiossa tutkimusta esille nousee jälkistrukturalistinen näkemys intertekstuaalisuudesta osana lukijan tuottaman merkityksen tulkinnanvaraisuutta. Osiossa käsitellään Rembrandtin taideteosten roolia Smithin romaanissa ja analysoidaan hahmojen tulkintoja sekä suhtautumista Rembrandtin tuotantoon Barthesin teoreettisten käsitteiden kautta. Keskeiseksi analyysin kohteeksi nousee lukija sekä lukijan tuottamat tulkinnat ja niiden merkitys Smithin romaanin tematiikassa. Tutkielmassa osoitetaan kuinka intertekstuaalisuus ei ole niin yksinkertainen termi kuin sen laaja käyttö niin kirjallisuustieteessä kuin mediassakin antaa ymmärtää, sekä selvitetään intertekstuaalisuuden teorian kehitystä 60-luvulta nykypäivään. Vaikka strukturalistisessa muodossa käsite soveltuu etenkin kahden toisiinsa kytkeytyneen teoksen tutkimiseen, vertaileva analyysi kuitenkin osoittaa, että On Beauty ei ole pelkkä uudelleenkirjoitus, vaan romaanin tulkintaan tarvitaan myös jälkistrukturalistisen dekonstruktion käsitteitä, jotta laajemmat tekstuaalisuuden verkostot aukeavat lukijalle. Romaanissa esiintyvä taitelijakuva myös osoittaa, että Smith itse on hyvin tietoinen kirjallisuusteoreettisesta keskustelusta.

Dental identification and aspects of medico-legal investigations of the Finnish victims of the Sumatra-Andaman earthquake on 26 December 2004

Tsunami waves of the Sumatra-Andaman earthquake on 26 December 2004 claimed approximately 230 000 lives and started the biggest identification operation in Interpol's history. The aim of this study was to resolve methods of the identification and results received. The viewpoint is mainly that of forensic odontology, but also includes other means of identification and results of the medico-legal examination performed in Finland. Of the 5395 victims in Thailand, approximately 2 400 were foreigners from 36 nations including 177 Finnish nationals. Additionally, a Finnish woman perished in Sri Lanka and a severely injured man after the evacuation in a hospital. The final numbers of missing persons and dead bodies registered in the Information Management Centre in Phuket,Thailand, were 3 574 ante-mortem (AM) and 3 681 post-mortem (PM) files. The number of identifications by December 2006 was 3 271 or 89% of the victims registered. Of Finnish victims, 172 have been identified in Thailand and 163 repatriated to Finland. One adult and four children are still missing. For AM data, a list of Finnish missing persons including 178 names was published on 30 December 2004. By February 2005 all useful dental AM data were available. Five persons on the list living in Finland lacked records. Based on the AM database, for the children under age 18 years (n=60) dental identification could be established for 12 (20%). The estimated number for adults (n=112) was 96 (86%). The final identification rate, based on PM examinations in Finland, was 14 (25%) for children (n= 56) and 98 (90%) for adults (n= 109). The number of Finnish victims identified by dental methods, 112 (68%), was high compared to all examined in Thailand (43%). DNA was applied for 26 Finnish children and for 6 adults, fingerprints for 24 and 7, respectively. In 12 cases two methods were applied. Every victim (n=165) underwent in Finland a medico-legal investigation including an autopsy with sampling specimens for DNA, the toxicological and histological investigation. Digital radiographs and computed tomography were taken of the whole body to verify autopsy findings and bring out changes caused by trauma, autolysis, and sampling for DNA in Thailand. Data for identification purposes were also noted. Submersion was the cause of death for 101 of 109 adults (92.7%), and trauma for 8 (7.3%). Injuries were 33 times contributing factors for submersion and 3 times for trauma-based death. Submersion was the cause of death for 51 (92.7%) children and trauma for 4 (7.3%). Injuries were in 3 cases contributing factors in submersion and once in trauma-based death. The success of the dental identification of Finnish victims is mainly based on careful registration of dental records, and on an education program from 1999 in forensic odontology.

Public and private technical assistance programs for non-industrial private forest landowners in the southern United States.

XVIII IUFRO World Congress, Ljubljana 1986.

Dietary aspects of cow's milk allergy in young children

Cow s milk allergy (CMA) affects about 2-6% of infants and young children. Environmental factors during early life are suggested to play a role in the development of allergic diseases. One of these factors is likely to be maternal diet during pregnancy and lactation. The association between maternal diet and development of CMA in offspring is not well known, but diet could contain factors that facilitate development of tolerance. After an established food allergy, another issue is gaining tolerance towards an antigen that causes symptoms. The strictness of the elimination depends on the individual level of tolerance. This study aimed at validating a questionnaire used to inquire about food allergies in children, at researching associations between maternal diet during pregnancy and lactation and subsequent development of cow s milk allergy in the offspring, and at evaluating the degree of adherence to a therapeutic elimination diet of children with CMA and factors associated with the adherence and age of recovery. These research questions were addressed in a prospective birth cohort born between 1997 and 2004 at the Tampere and Oulu University Hospitals. Altogether 6753 children of the Diabetes Prediction and Prevention (DIPP) Nutrition cohort were investigated. Questionnaires regarding allergic diseases are often used in studies without validation. High-quality valid tools are therefore needed. Two validation studies were conducted here: one by comparing parentally reported food allergies with information gathered from patient records of 1122 children, and the other one by comparing parentally reported CMA with information in the reimbursement records of special infant formulae in the registers of the Social Insurance Institution for 6753 children. Both of these studies showed that the questionnaire works well and is a valid tool for measuring food allergies in children. In the first validation study, Cohen s kappa values were within 0.71-0.88 for CMA, 0.74-0.82 for cereal allergy, and 0.66-0.86 for any reported food allergy. In the second validation study, the kappa value was 0.79, sensitivity 0.958, and specificity 0.965 for reported and diagnosed CMA. To investigate the associations between maternal diet during pregnancy and lactation and CMA in offspring, 6288 children were studied. Maternal diet during pregnancy (8th month) and lactation (3rd month) was assessed by a validated, 181-item semi-quantitative food frequency questionnaire (FFQ), and as an endpoint register-based information on diagnosed CMA was obtained from the Social Insurance Institution and complemented with parental reports of CMA in their children. The associations between maternal food consumption and CMA in offspring were analyzed by logistic regression comparing the highest and lowest quarters with two middle quarters of consumption and adjusted for several potential confounding factors. High maternal intake of milk products (OR 0.56, 95% CI 0.37-0.86 p = 0.002) was associated with a lower risk of CMA in offspring. When stratified according to maternal allergic rhinitis or asthma, a protective association of high use of milk products with CMA was seen in children of allergy-free mothers (OR 0.30, 95% CI 0.13 - 0.69, p < 0.001), but not in children of allergic mothers. Moreover, low maternal consumption of fish during pregnancy was associated with a higher risk of CMA in children of mothers with allergic rhinitis or asthma (OR 1.47, 95% CI 0.96 - 2.27 for the lowest quarter, p = 0.043). In children of nonallergic mothers, this association was not seen. Maternal diet during lactation was not associated with CMA in offspring, apart from an inverse association between citrus and kiwi fruit consumption and CMA. These results imply that maternal diet during pregnancy may contain factors protective against CMA in offspring, more so than maternal diet during lactation. These results need to be confirmed in other studies before giving recommendations to the public. To evaluate the degree of adherence to a therapeutic elimination diet in children with diagnosed CMA, food records of 267 children were studied. Subsequent food records were examined to assess the age at reintroduction of milk products to the child s diet. Nine of ten families adhered to the elimination diet of the child with extreme accuracy. Older and monosensitized children had more often small amounts of cow s milk protein in their diet (p < 0.001 for both). Adherence to the diet was not related to any other sociodemographic factor studied or to the age at reintroduction of milk products to the diet. Low intakes of vitamin D, calcium, and riboflavin are of concern in children following a cow s milk-free diet. In summary, we found that the questionnaires used in the DIPP study are valid in investigating CMA in young children; that there are associations between maternal diet during pregnancy and lactation and the development of CMA in offspring; and that the therapeutic elimination diet in children with diagnosed CMA is rigorously adhered to.