scholarly journals Probabilistic multi-catalogue positional cross-match

2017 ◽  
Vol 597 ◽  
pp. A89 ◽  
Author(s):  
F.-X. Pineau ◽  
S. Derriere ◽  
C. Motch ◽  
F. J. Carrera ◽  
F. Genova ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Cross Correlation ◽  
High Energy ◽  
Chi Square ◽  
Bayes Formula ◽  
Astrophysical Objects ◽  
Multi Wavelength ◽  
Chi Square Test ◽  
Cross Matching ◽  
Cross Match

Context. Catalogue cross-correlation is essential to building large sets of multi-wavelength data, whether it be to study the properties of populations of astrophysical objects or to build reference catalogues (or timeseries) from survey observations. Nevertheless, resorting to automated processes with limited sets of information available on large numbers of sources detected at different epochs with various filters and instruments inevitably leads to spurious associations. We need both statistical criteria to select detections to be merged as unique sources, and statistical indicators helping in achieving compromises between completeness and reliability of selected associations. Aims. We lay the foundations of a statistical framework for multi-catalogue cross-correlation and cross-identification based on explicit simplified catalogue models. A proper identification process should rely on both astrometric and photometric data. Under some conditions, the astrometric part and the photometric part can be processed separately and merged a posteriori to provide a single global probability of identification. The present paper addresses almost exclusively the astrometrical part and specifies the proper probabilities to be merged with photometric likelihoods. Methods. To select matching candidates in n catalogues, we used the Chi (or, indifferently, the Chi-square) test with 2(n−1) degrees of freedom. We thus call this cross-match a χ-match. In order to use Bayes’ formula, we considered exhaustive sets of hypotheses based on combinatorial analysis. The volume of the χ-test domain of acceptance – a 2(n−1)-dimensional acceptance ellipsoid – is used to estimate the expected numbers of spurious associations. We derived priors for those numbers using a frequentist approach relying on simple geometrical considerations. Likelihoods are based on standard Rayleigh, χ and Poisson distributions that we normalized over the χ-test acceptance domain. We validated our theoretical results by generating and cross-matching synthetic catalogues. Results. The results we obtain do not depend on the order used to cross-correlate the catalogues. We applied the formalism described in the present paper to build the multi-wavelength catalogues used for the science cases of the Astronomical Resource Cross-matching for High Energy Studies (ARCHES) project. Our cross-matching engine is publicly available through a multi-purpose web interface. In a longer term, we plan to integrate this tool into the CDS XMatch Service.

scholarly journals Confronting Theories of Firm Growth in Light of Degrees-of-Freedom Analysis

2015 ◽  
Vol 22 (74) ◽  
pp. 385-404
Author(s):  
Sérgio Fernando Loureiro Rezende ◽  
Ricardo Salera ◽  
José Márcio de Castro
Keyword(s):  
Degrees Of Freedom ◽  
Firm Growth ◽  
Dynamic Capabilities ◽  
Statistical Tests ◽  
Explanatory Power ◽  
Stage Theory ◽  
Chi Square ◽  
Growth Optimum ◽  
Chi Square Test ◽  
Do So

This article aims to confront four theories of firm growth – Optimum Firm Size, Stage Theory of Growth, The Theory of the Growth of the Firm and Dynamic Capabilities – with empirical data derived from a backward-looking longitudinal qualitative case of the growth trajectory of a Brazilian capital goods firm. To do so, we employed Degree of Freedom-Analysis for data analysis. This technique aims to test the empirical strengths of competing theories using statistical tests, in particular Chi-square test. Our results suggest that none of the four theories fully explained the growth of the firm we chose as empirical case. Nevertheless, Dynamic Capabilities was regarded as providing a more satisfactory explanatory power.

The Application of the Chi-Square Test of Goodness-of-Fit to Mortality Data Graduated by Summation Formulae.

1971 ◽  
Vol 97 (2-3) ◽  
pp. 325-330 ◽  
Author(s):  
J. H. Pollard
Keyword(s):  
Degrees Of Freedom ◽  
Goodness Of Fit ◽  
Summation Formula ◽  
Mortality Data ◽  
Goodness Of Fit Test ◽  
Chi Square ◽  
Summation Formulae ◽  
Chi Square Test

In his paper of 1941, Seal included details of some experiments he performed in an attempt to estimate the appropriate number of degrees of freedom for the chi-square goodness-of-fit test of a summation formula graduation. These results are referred to by Tetley and by Benjamin and Haycocks in their textbooks when they mention the difficulty of determining the number of degrees of freedom or mean chi-square value.

184 EFFECTS OF X-RAY ELECTROMAGNETIC RADIATION ON BOVINE OOCYTE DEVELOPMENT

2010 ◽  
Vol 22 (1) ◽  
pp. 250
Author(s):  
W. E. Snyder ◽  
J. T. Aaltonen ◽  
H. D. Sigal ◽  
N. M. Loskutoff
Keyword(s):  
Electromagnetic Radiation ◽  
High Energy ◽  
X Rays ◽  
Embryo Production ◽  
Chi Square ◽  
X Ray ◽  
Chi Square Test ◽  
Bovine Oocytes ◽  
Experimental Group

This study examined the effects of X-rays on bovine oocytes used for in vitro embryo production. In recent years, airport security has become more stringent and the use of X-ray screening may be required for all items, which could be problematic when transporting oocytes. Ionizing radiation such as X-rays are high-energy particles that can penetrate into the nucleus of a cell and cause single and double-strand breaks in the DNA chain. Oocytes exposed to X-ray radiation may have DNA damage affecting maturation, fertilization, and embryonic development. Bovine ovaries obtained from a local abattoir were used to collect immature oocytes by follicular aspiration. The oocytes were divided into a control group and an experimental group then placed in maturation medium. The oocytes in the experimental group were placed in a hospital X-ray machine with a single exposure of 100 mA, 120 kVp for 0.3 s. This exposure challenged the oocytes with a comparable, calculated amount of mrems equivalent to a single screening from an airport X-ray machine (30 mrems). After X-ray exposure, the experimental group was cultured with the control at 37°C and 5% CO2. After 18 h, cryopreserved bovine sperm were thawed and processed using BoviPure (Nidacon International, Mölndal, Sweden) density gradient centrifugation and the oocytes were inseminated with 1 × 106 sperm in fertilization medium at 37°C and 5% CO2. After 24 h, both groups were transferred to 50-μL droplets of G1 medium (Vitrolife, Göteborg, Sweden) at 37°C and 6% CO2 and both were transferred into G2 medium after 72 h. Development of the oocytes was scored after an additional 72 h. Results were based on 2 criteria: the percent cleaved (presumptive fertilization) and the percent cleaved that developed to morula and blastocyst stages. The results indicated no significant difference in the percentages of oocytes cleaving after insemination for the control and experimental groups (P = 0.403, chi-square test). However, there was a significant increase (P = 0.037, chi-square test) in the percentages of morulae and blastocysts developing in the control (non-irradiated) v. experimental (X-rayed) groups. The outcome of this study cautions on the potential damage caused to bovine oocytes used for embryo production in vitro when exposed to X-ray electromagnetic radiation during routine air transport screening operations. Table 1.

Ultraviolet Luminous Objects in GALEX data: search and possible explanation of their nature

2020 ◽  
pp. 71-80
Author(s):  
O.Yu MALKOV ◽  
S.V KARPOV ◽  
G ZHAO
Keyword(s):  
Wave Band ◽  
Milky Way Galaxy ◽  
Single Wave ◽  
Astrophysical Objects ◽  
Multi Wavelength ◽  
Uv Excess ◽  
Luminous Objects ◽  
Cross Matching ◽  
Selection Of

Multi-wavelength characterization of astrophysical objects by means of cross-matching of modern large sky surveys is a powerful tool intensively used for classification, parameterization and studies of various classes of sources. The objects detected in many or all surveys under study represent convenient material for the research, however, objects that are found in only one of the surveys, and absent in all others, should also attract close attention. Our goal is to identify and study objects apparent in only a single wave band, and invisible in the others. It is still a relatively poorly investigated field and may lead to the detection of a new unique (or transient) class of objects. Here we explore the possibility of detecting of objects with a significant UV excess in their spectra by cross-matching of the GALEX all-sky catalogue with several other surveys in different wavelength ranges and analyzing the ones visible in GALEX only (ultraviolet luminous objects). We describe the methodology for such investigation, explain the selection of surveys for this study, and show initial results based on the search in several small sky areas. The ultraviolet luminous objects should reside in the Milky Way Galaxy and must be either very hot massive stars in the main sequence stage of their evolution, or isolated old neutron stars, slowly accreting interstellar matter. Our results will be used as an input for a larger-scale investigation.

scholarly journals Functional capacity assessment of long-lived older adults from Amazonas

2019 ◽  
Vol 72 (suppl 2) ◽  
pp. 49-55 ◽  
Author(s):  
Daiane de Souza Fernandes ◽  
Lucia Hisako Takase Gonçalves ◽  
Angela Maria Rodrigues Ferreira ◽  
Maria Izabel Penha de Oliveira Santos
Keyword(s):  
Older Adults ◽  
Functional Capacity ◽  
Functional Independence Measure ◽  
Functional Independence ◽  
High Energy ◽  
Capacity Assessment ◽  
Cognitive Screening ◽  
Chi Square ◽  
Cross Sectional ◽  
Chi Square Test

ABSTRACT Objective: To evaluate the functional capacity of long-lived older adults from Amazonas. Method: A cross-sectional epidemiological study was carried out with 116 older adults aged 80 years or older, registered in a primary health care unit in Belém, in the state of Pará, Brazil. The Functional Independence Measure (FIM) was used for functional capacity assessment and the Mini-Mental State Examination (MMSE) for cognitive screening. Univariate and bivariate analyses were carried out, in addition to the Pearson’s chi-square test. Results: The older adults presented modified independence in the self-care, sphincter control and locomotion dimensions, and needed supervision for mobility/transfers. In mobility, men presented complete independence. Modified independence was found in the 80-89 age group. It was observed that, the lower the education level, the worse the cognitive performance. Conclusion: In spite of their advanced age, long-lived older adults still present functional capacity for activities of daily living, even though they required supervision for high energy expenditure tasks, such as mobility and transfers.

scholarly journals HUBUNGAN KEPUASAN PELAYANAN MAKANAN DENGAN TINGKAT KECUKUPAN ENERGI DAN PROTEIN PASIEN DI RUMAH SAKIT UNIVERSITAS AIRLANGGA SURABAYA

2017 ◽  
Vol 11 (1) ◽  
pp. 32
Author(s):  
Amanda Nurqisthy ◽  
Merryana Adriani ◽  
Lailatul Muniroh
Keyword(s):  
Patient Satisfaction ◽  
Food Service ◽  
High Energy ◽  
Service Satisfaction ◽  
Food Services ◽  
Chi Square ◽  
Patient’S Satisfaction ◽  
Chi Square Test ◽  
Hospital Food Service ◽  
The Relationship

Patient’s satisfaction is one of success indicator of hospital food service, which affect the level of energy and protein sufficiency of patients. The aim of this study was to analyze the relationship between food service satisfaction and energy and protein suffi ciency level of patients in Universitas Airlangga Hospital. Thirty-four samples who receive High Energy and Protein diet were chosen using purposive sampling. Patient satisfaction data was collected through interview using a questionnaire and food waste was analyze through observation by Comstock method. Data was processed using chi square test. The result showed that level of energy and protein suffi ciency of most patients are adequate (73.5% and 70.6%) and most patient are satisfi ed with the hospital food service (76.5%). There was a relationship between satisfaction of food service with the level of energy and protein suffi ciency of patients (p = 0.017 and p = 0.031). Patients who were satisfi ed with the food services of hospital has a suffi cient intake of energy and protein. It is needed to restore system of food operation in hospital, especially on the punctuality of food distributionand fl avor of food, considering that those indicator, were source of dissatisfaction.Keywords: food service satisfaction, patients, the level of energy and protein suffi ciency

Hubungan Upaya Ibu dalam Mempersiapkan Masa Pubertas dengan Perilaku Seksual Remaja

2020 ◽  
Vol 7 (2) ◽  
pp. 301-306
Author(s):  
Yona Septina
Keyword(s):  
Sexual Behavior ◽  
Risky Sexual Behavior ◽  
Random Sampling ◽  
Degrees Of Freedom ◽  
P Value ◽  
Adolescent Sexual Behavior ◽  
Chi Square ◽  
A Value ◽  
Chi Square Test

Rendahnya kontrol orang tua terhadap prilaku seksual remaja dapat menyebabkan remaja melakukan prilaku seksual yang beresiko. Penelitian ini bertujuan untuk mengetahui hubungan upaya ibu dalam mempersiapkan masa pubertas dengan perilaku seksual remaja di Desa Sukamantri Kecamatan Sukamantri Kabupaten Ciamis tahun 2016. Penelitian ini merupakan penelitian deskriptif analitik. Populasi dalam penelitian ini adalah seluruh remaja awal usia 12 sampai 15 di Desa Sukamantri Kecamatan Sukamantri Kabupaten Ciamis tahun 2016 sebanyak 1.113 orang. Ukuran sampel yang digunakan adalah sebanyak 92 orang dengan cara random sampling dan menggunakan rumus slovin. Instrumen penelitian menggunakan angket dengan skala Guttman. Uji hipotesis menggunakan uji Chi-Square. Hasil penelitian menunjukan bahwa upaya ibu dalam mempersiapkan masa pubertas di di Desa Sukamantri Kabupaten Ciamis termasuk kategori baik 53,3% dan kurang 46,7%. Perilaku seksual remaja di Desa Sukamantri Kabupaten Ciamis  termasuk kategori baik 56,5% dan buruk 43,5%. Hubungan upaya ibu mempersiapkan masa pubertas dengan perilaku seksual remaja di Desa Sukamantri Kabupaten Ciamis dengan nilai 2 = 80,644 dengan derajat kebebasan (df) 1 dan p-value atau Sig 0,000, dapat disimpulkan bahwa ada hubungan signifikan antara upaya ibu dalam mempersiapkan pubertas dengan dengan prilaku seksual remaja sehingga peran ibu dalam mempersiapkan masa remaja sangat penting untuk dilakukan. Low parental control over adolescent sexual behavior can cause teens to engage in risky sexual behavior. This study aimed to determine the correlation of maternal efforts in preparing for puberty and teenage sexual behavior in Sukamantri Village, Sukamantri District, Ciamis Regency in 2016. This study was a descriptive analytic study. The population in this study was all early teens aged 12 to 15 in Sukamantri Village, Sukamantri District, Ciamis Regency in 2016 as many as 1,113 people. The sample was 92 people taken by random sampling and using the Slovin formula. The instrument used a Guttman scale questionnaire. The hypothesis testing used the Chi-Square test. The results showed that maternal efforts in preparing for puberty in Sukamantri Village, Ciamis Regency were 53.3% in the good category and 46.7% less in the lack category. Teenage sexual behavior in Sukamantri Village, Ciamis Regency was 56.5% in the good category and 43.5% in bad category. The correlation ofmaternal efforts to prepare for puberty and adolescent sexual behavior in Sukamantri Village, Ciamis Regency with a value of 2 = 80,644 with degrees of freedom (df) 1 and p-value or Sig 0,000. It could be concluded that there was a significant correlation between maternal efforts in preparing puberty with teenage sexual behavior. The role of mothers in preparing for adolescence is very important things to do.

scholarly journals Pengetahuan Akseptor Tentang KB Suntik 3 Bulan Dengan Ketepatan Waktu Kunjungan Ulang di BPRB Bina Sehat Kasihan, Bantul, Yogyakarta

2016 ◽  
Vol 3 (2) ◽  
pp. 103
Author(s):  
Sri Lestari ◽  
Susiana Sariyati ◽  
Wahyuningsih Wahyuningsih
Keyword(s):  
Family Planning ◽  
Degrees Of Freedom ◽  
P Value ◽  
Knowledge Level ◽  
Chi Square ◽  
Cross Sectional ◽  
Test Analysis ◽  
High Knowledge ◽  
Chi Square Test ◽  
Cross Sectional Design

<p>Family planning (FP) program has important role in realizing Indonesian people prosperous, besides health and education program. Contraceptive injection high effectiveness if the injection carried out regularly and appropriate schedule. Promptness revisit in FP injection is infl uenced by acceptors knowledge about FP injection and supported with a good memory. The knowledge level is one factor that causing acceptors choosing or not a method of contraception. The purpose of this study was to know relationship between knowledge level of acceptors and three months contraception injection with promptness revisit. This study was an observational analytic with cross sectional design. Technique sampling used was purposive sampling, resulted on 63 respondents. The study was done by granting the questionnaire to acceptors who revisit at BPRB Bina Sehat Kasihan Bantul In July 2014. Test analysis used chi-square. The results showed that knowledge of acceptors family planning about 3 months injection was 57 (90.5%) respondents in high knowledge. Timeliness revisit of acceptors 3 months injection was 60 (95.2%) respondents revisit timely. According to the analysis of using formulas chi-square test with standard signifi cance 0.05 and degrees of freedom 1, obtained chi-square count was 0.332 or p-value 0.565 while chi-square table was 3.841. In conclusion, there was no relationship between knowledge level of acceptors family planning and 3 months injection with promptness revisit at BPRB Bina Sehat Kasihan Bantul.</p>

scholarly journals CLIMA ORGANIZACIONAL COMO FACTOR EN LA SATISFACCIÓN LABORAL DE UNA EMPRESA DE SERVICIOS

2020 ◽  
Vol 13 (21) ◽  
pp. 15
Author(s):  
Karina Govea Andrade ◽  
Doménica Zuñiga Briones
Keyword(s):  
Job Satisfaction ◽  
Organizational Climate ◽  
Work Environment ◽  
Degrees Of Freedom ◽  
Chi Square ◽  
Satisfaction Scale ◽  
Service Company ◽  
Environment Scale ◽  
Chi Square Test ◽  
Support Autonomy

En el presente trabajo se determinó la relación positiva entre el clima organizacional y la satisfacción laboral, mediante una investigación no experimental de alcance descriptivo y correlacional en una población de 40 colaboradores dentro de una empresa de servicios en la ciudad de Guayaquil, Ecuador. El instrumento utilizado para analizar el clima organizacional fue el cuestionario de Work Environment Scale (WES) de Moos compuesto por 90 ítems que integra factores como implicación, cohesión, apoyo, autonomía, organización, presión, claridad, control, innovación y comodidad; mientras que, para la satisfacción laboral se utilizó la escala de satisfacción de Warr, Cook y Wall que consta de 15 interrogantes para medir la satisfacción intrínseca y extrínseca. Los resultados fueron procesados mediante tablas de frecuencia de datos obtenidos y datos esperados con un nivel de confianza del 90% y con 4 de grados de libertad. Los resultados indicaron que 24 personas estuvieron conformes con el clima organizacional de la empresa, en cambio y para la satisfacción laboral se obtuvieron 32 personas satisfechas. Para comprobar las hipótesis planteadas, complementándose con la encuesta realizada, se utilizó la prueba chi-cuadrado obteniendo 10,57, en comparación con el chi-crítico de 7,779, se determinó que la relación entre el clima organizacional y la satisfacción laboral es positiva.Palabras Claves: Clima organizacional, Satisfacción laboral, Empresa de Servicios. AbstractIn the present work we determined the positive relationship between organizational climate and job satisfaction, through a quantitative, non-experimental research in a population of 40 staff within a service company in the city of guayaquil-ecuador. The instrument used to analyze the organizational climate was the Questionnaire of Work Environment Scale (WES) Moos composed of 90 items that integrates factors such as involvement, cohesion, support, autonomy, organization, pressure, clarity, control, innovation and comfort; while, for job satisfaction was used the satisfaction scale of Warr, Cook and Wall that consists of 15 questions to measure the intrinsic and extrinsic satisfaction. The results were processed using frequency tables of data obtained and expected data with a confidence level of 90% and with 4 degrees of freedom. The results indicated that 24 people were satisfied with the organizational climate of the company, in change and job satisfaction were obtained 32 people met. To test the hypothesis raised, along with the survey, the chi-square test was used getting 10.57, compared with the chi-critical of 7.779, it was determined that the relationship between the organizational climate and job satisfaction is positive.Keywords: Organizational climate, job satisfaction, Service Company.

scholarly journals C3: A Command-line Catalogue Cross-matching tool for modern astrophysical survey data

2016 ◽  
Vol 12 (S325) ◽  
pp. 327-332
Author(s):  
Giuseppe Riccio ◽  
Massimo Brescia ◽  
Stefano Cavuoti ◽  
Amata Mercurio ◽  
Anna Maria Di Giorgio ◽  
...  
Keyword(s):  
High Performance ◽  
Current Data ◽  
Command Line ◽  
Analysis Pipeline ◽  
Analysis Techniques ◽  
Generic Data ◽  
Multi Wavelength ◽  
Line Process ◽  
Cross Matching ◽  
Cross Match

AbstractIn the current data-driven science era, it is needed that data analysis techniques has to quickly evolve to face with data whose dimensions has increased up to the Petabyte scale. In particular, being modern astrophysics based on multi-wavelength data organized into large catalogues, it is crucial that the astronomical catalog cross-matching methods, strongly dependant from the catalogues size, must ensure efficiency, reliability and scalability. Furthermore, multi-band data are archived and reduced in different ways, so that the resulting catalogues may differ each other in formats, resolution, data structure, etc, thus requiring the highest generality of cross-matching features. We presentC3(Command-line Catalogue Cross-match), a multi-platform application designed to efficiently cross-match massive catalogues from modern surveys. Conceived as a stand-alone command-line process or a module within generic data reduction/analysis pipeline, it provides the maximum flexibility, in terms of portability, configuration, coordinates and cross-matching types, ensuring high performance capabilities by using a multi-core parallel processing paradigm and a sky partitioning algorithm.

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