1,078 research outputs found
The impact of non-cognitive skills and risk preferences on rural-to-urban migration: Evidence from Ukraine
This paper provides evidence on the impacts of non-cognitive skills and attitudes towards risk on the decision to migrate from rural to urban areas. Our analysis is based on a unique four-wave panel of Ukrainian Longitudinal Monitoring Survey for the period between 2003 and 2012. Adopting the Five Factor Model of personality structure, and using it in the evaluation of non-cognitive skills, our results suggest that such personality traits as openness to new experience and the willingness to take risks increase the probability of migration. On the other hand, the non-cognitive skills conscientiousness and extraversion are found to be negatively associated with the propensity to migrate. The effects are statistically and quantitatively significant, and mainly driven by movements from rural areas into cities. Our results are robust to several sensitivity checks, including tests for reverse causality
SEQUENTIAL DATA WEIGHTING PROCEDURES FOR COMBINED RATIO ESTIMATORS IN COMPLEX SAMPLE SURVEYS
In sample surveys weighting is applied to data to increase the quality of estimates. Data weighting can be used for several purposes. Sample design weights can be used to adjust the differences in selection probabilities for non-self weighting sample designs. Sample design weights, adjusted for nonresponse and non-coverage through the sequential data weighting process. The unequal selection probability designs represented the complex sampling designs. Among many reasons of weighting, the most important reasons are weighting for unequal probability of selection, compensation for nonresponse, and post-stratification. Many highly efficient estimation methods in survey sampling require strong information about auxiliary variables, x. The most common estimation methods using auxiliary information in estimation stage are regression and ratio estimator. This paper proposes a sequential data weighting procedure for the estimators of combined ratio mean in complex sample surveys and general variance estimation for the population ratio mean. To illustrate the utility of the proposed estimator, Turkish Demographic and Health Survey 2003 real life data is used. It is shown that the use of auxiliary information on weights can considerably improve the efficiency of the estimates
Comprehensive Synthesis of Monohydroxy-Cucurbit[n]urils (n=5, 6, 7, 8): High Purity and High Conversions
We describe a photochemical method to introduce a single alcohol function directly on cucurbit[n]urils (n = 5, 6, 7, 8) with conversions of the order 95-100% using hydrogen peroxide and UV light. The reaction was easily scaled up to 1 g for CB[6] and CB[7]. Spin trapping of cucurbituril radicals combined with MS experiments allowed us to get insights about the reaction mechanism and characterize CB [5], CB[6], CB[7], and C13[8] monofunctional compounds. Experiments involving O-18 isotopically labeled water indicated that the mechanism was complex and showed signs of both radical and ionic intermediates. DFT calculations allowed estimating the Bond Dissociation Energies (BDEs) of each hydrogen atom type in the CB series, providing an explanation of the higher reactivity of the "equatorial" C-H position of CB[n] compounds. These results also showed that, for CB [8], direct functionalization on the cucurbituril skeleton is more difficult because one of the methylene hydrogen atoms (H-b) has its BDE lowering within the series and coming close to that of H-c, thus opening the way to other types of free radicals generated on the CB[8] skeleton leading to several side products. Yet CB[5]-(OH)(1) and CB[8]-(OH)(1), the first CB[8] derivative, were obtained in excellent yields thanks to the soft method presented here
High binding yet accelerated guest rotation within a cucurbit[7]uril complex. Toward paramagnetic gyroscopes and rolling nanomachines
Your spouse is fired! How much do you care?
This study is the first to provide a causal estimate of the cross-spouse subjective well-being consequences of unemployment. Using German panel data on married and cohabiting partners for 1991-2015 and information on exogenous unemployment entry due to workplace closure, we show that one spouse's unemployment experience reduces the life satisfaction of the other partner. The estimated spillover is at least one quarter of the effect of own unemployment and is equally pronounced among female and male partners. In addition, while wives' life satisfaction does not recover even two years after their partners becoming unemployed, husbands only react to their wives' joblessness during the first year of unemployment. Our results are insensitive to income controls and the couple's position in the income distribution, thus reflecting the non-pecuniary costs of unemployment. Although the income loss hardly explains the negative spillover effects of unemployment on spousal life satisfaction, we document large declines in spousal satisfaction with household income and living standards. This finding supports the argument that the costs of unemployment borne by indirectly affected spouses extend beyond the loss of consumption opportunities and might be rather related to social values attached to market work. Being robust to a battery of sensitivity checks, our findings imply that public policy programs aimed at mitigating unemployment's negative consequences need to target not only those directly affected but also cohabiting spouses.</p
Dataset for Metal-Organic Fireworks! MOFs as Structural Scaffolds for Pyrotechnic Materials
A new approach to formulating pyrotechnic materials is presented whereby constituent ingredients are bound together in a solid-state lattice in the form of a Metal-Organic Framework. This reduces the batch inconsistencies arising from the traditional approach of combining powders by ensuring the key ingredients are ‘mixed’ in stoichiometric quantities and are in intimate contact. Further benefits for the application of these types of material are increased safety levels as well as simpler logistics, storage and manufacture. A systematic series of new frameworks comprising fuel and oxidiser agents (group 1 and 2 metal nodes and terephthalic acid derivatives as linkers) has been synthesised and structurally characterised. These new materials have been assessed for pyrotechnic effect by calorimetry and burn tests. Results indicate that these materials exhibit the desired properties of a pyrotechnic mate-rial and that the effect can be correlated to the di-mensionality of the structure.</span
SINIFLANDIRMA SONRASI KARŞILAŞTIRMA TEKNİĞİ KULLANILARAK HETEROJEN YAPIYA SAHİP ORMANLARDA ZAMANSAL DEĞİŞİMLERİN BELİRLENMESİ
Bu çalışmada, sınıflandırma sonrası karşılaştırma yöntemi kullanılarak, Batı Karadeniz Bölgesi’nde yayılış gösteren ve ağaç türü, gelişim çağı, kapalılık gibi yapısal özellikleri bakımından farklılıklar içeren meşcerelere sahip ormanlarda oluşan zamansal değişimlerin belirlenmesi amaçlanmıştır. 1987 ve 2000 yılı Landsat uydu görüntülerine en yüksek olabilirlik algoritması ile kontrollü sınıflandırma işlemi uygulanmıştır. Sınıflandırılmış görüntülerin doğrulukları hata matrisleri kullanılarak değerlendirilmiş ve genel kappa istatistikleri sırasıyla 0.8543 ve 0.9038 olarak hesaplanmıştır. Elde edilen değişim matrisinde, farklı ana bilgi sınıfları arasındaki geçişler incelendiğinde, toplam alanın %29.77’sinde değişim belirlenmiştir. Sonuç olarak, Landsat uydu veri setinin kullanıldığı bu çalışmada, sınıflandırma sonrası karşılaştırma yöntemi ile çalışma alanındaki heterojen yapıya sahip ormanlarda oluşan zamansal değişimlerin sınırlı detayda ancak yüksek doğrulukla belirlenebildiği ortaya konulmuştur.
Anahtar Kelimeler: Sınıflandırma sonrası karşılaştırma, Değişim analizi, Uzaktan Algılam
An Investigation of Stationarity Properties of the Turkish Tourism Income Variable
Tourism has a significant impact on economic growth as put forth by the tourism-led
growth hypothesis. Turkey’s earnings from tourism were 31.5 billion dollars in 2015
according to TURKSTAT. This implies that tourism is an important industry for Turkey
and has a significant impact on economy. Therefore, the question whether a policy
implementation in tourism is long-lasting or not is critical for both the industry and whole
economy. This study researches the persistence of policies in tourism industry, employing
tourism income series for period of 2009M1-2015M12 and tests the stationarity of this
series using traditional unit root tests as well as a wavelet-based unit root test developed
by Fan and Gencay (2010). Both seasonally adjusted and unadjusted series have been
used. The empirical results point out that the traditional unit root test has a proclivity to
report that tourism income series is I(1) or non-stationary. On the other hand, the waveletbase unit root test indicates that tourism income is stationary. The empirical result of
wavelet-based test implies that impact of a shock on this sector is transitory. The income
in tourism industry will return more or less back to its meaning the following year
PETEK DOLGULU LEVHALAR ve FARKLI YAPIM TEKNİKLERİ İLE ÜRETİLMİŞ “L” TİPİ MOBİLYA KÖŞE BİRLEŞTİRMELERİN MOMENT TAŞIMA KAPASİTELERİ
Bu çalışmada, farklı yapım teknikleri ve kağıt petek dolgulu levhalar ile üretilmiş kutu tipi mobilya köşe birleştirmelerin moment taşıma kapasiteleri araştırılmıştır. Deneylerde 38 mm kalınlığında kağıt petek dolgulu levhalar kullanılarak, “L” tipi olarak üretilmiş kutu konstrüksiyonlu mobilya köşe birleştirmelerde kavela, minifiks, maksifiks, bisküvi ve özel bağlantı birleştirmeleri uygulanmıştır. Deneylerde ahşap esaslı levha olarak 4 ve 8 mm kalınlığında yonga levha (YL) ve orta yoğunlukta lif levha (MDF) kullanılmıştır. Tutkallı birleştirmelerde polivinilasetat (PVAc) tutkalı kullanılmıştır. Deney örnekleri, kullanım sırasında etkisinde kalabilecekleri kritik yükler göz önüne alınarak statik diyagonal basınç yükü altında test edilmiştir. Deney sonuçlarına göre, MDF ile üretilen bisküvi ve kavelalı deney örnekleri daha fazla moment taşımıştır. Diyagonal basınç deneyi sonuçlarına göre; kutu konstrüksiyonlu mobilya tasarımında ekonomik kriterler de dikkate alınarak malzeme tercihi, MDF ve yongalevha şeklinde yapılmalıdır. Tutkallı birleştirmelerde bisküvi, tukalsız demonte birleştirmelerde ise minifix birleştirme tercih edilmelidir. Konu ile ilgili malzeme ve birleştirmeler farklı varyasyonlar şeklinde denenebilir
- …