Bayesian Ideas in Survey Sampling: The Legacy of Basu

Survey sampling and, more generally, Official Statistics are experiencing an important renovation time. On one hand, there is the need to exploit the huge information potentiality that the digital revolution made available in terms of data. On the other hand, this process occurred simultaneously with a progressive deterioration of the quality of classical sample surveys, due to a decreasing willingness to participate and an increasing rate of missing responses. The switch from survey-based inference to a hybrid system involv- ing register-based information has made more stringent the debate and the possible resolution of the design-based versus model-based approaches con- troversy. In this new framework, the use of statistical models seems unavoid- able and it is today a relevant part of the official statistician toolkit. Models are important in several different contexts, from Small area estimation to non sampling error adjustment, but they are also crucial for correcting bias due to over and undercoverage of administrative data, in order to prevent potential selection bias, and to deal with different definitions and/or errors in the measurement process of the administrative sources. The progressive shift from a design-based to a model-based approach in terms of super-population is a matter of fact in the practice of the National Statistical Institutes. How- ever, the introduction of Bayesian ideas in official statistics still encounters difficulties and resistance. In this work, we attempt a non-systematic review of the Bayesian development in this area and try to highlight the extra ben- efit that a Bayesian approach might provide. Our general conclusion is that, while the general picture is today clear and most of the basic topics of survey sampling can be easily rephrased and tackled from a Bayesian perspective, much work is still necessary for the availability of a ready-to-use platform of Bayesian survey sampling in the presence of complex sampling design, non-ignorable missing data patterns, and large datasets

A stochastic estimated version of the Italian dynamic General Equilibrium Model (IGEM)

We estimate with Bayesian techniques the Italian dynamic General Equilibrium Model (IGEM), which has been developed at the Italian Treasury Department, Ministry of Economy and Finance, to assess the effects of alter-native policy interventions. We analyze and discuss the estimated effects of various shocks on the Italian economy. Compared to the calibrated version used for policy analysis, we find a lower wage rigidity and higher adjustment costs. The degree of prices and wages indexation to past inflation is much smaller than the indexation level assumed in the calibrated model. No substantial difference is found in the estimated monetary parameters. Estimated fiscal multipliers are slightly smaller than those obtained from the calibrated version of the model

10-Gb/s Operation of a Colorless Self-Seeded Transmitter Over More Than 70 km of SSMF

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Self-Seeded RSOA-Fiber Cavity Lasers vs. ASE Spectrum-Sliced or Externally Seeded Transmitters—A Comparative Study

Reflective semiconductor optical amplifier fiber cavity lasers (RSOA-FCLs) are appealing, colorless, self-seeded, self-tuning and cost-efficient upstream transmitters. They are of interest for wavelength division multiplexed passive optical networks (WDM-PONs) based links. In this paper, we compare RSOA-FCLs with alternative colorless sources, namely the amplified spontaneous emission (ASE) spectrum-sliced and the externally seeded RSOAs. We compare the differences in output power, signal-to-noise ratio (SNR), relative intensity noise (RIN), frequency response and transmission characteristics of these three sources. It is shown that an RSOA-FCL offers a higher output power over an ASE spectrum-sliced source with SNR, RIN and frequency response characteristics halfway between an ASE spectrum-sliced and a more expensive externally seeded RSOA. The results show that the RSOA-FCL is a cost-efficient WDM-PON upstream source, borrowing simplicity and cost-efficiency from ASE spectrum slicing with characteristics that are, in many instances, good enough to perform short-haul transmission. To substantiate our statement and to quantitatively compare the potential of the three schemes, we perform data transmission experiments at 5 and 10 Gbit/s

Self-Seeded RSOAs WDM PON Field Trial for Business and Mobile Fronthaul Applications

GEth, CPRI and 10 Gbit/s transmissions are experimented using amplified and standard self-seeded RSOA WDM PON systems. A field trial setup was exploited to test the system performance in terms of reach and optical budget

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Emergenza abitativa e baracche a Roma tra le due guerre

La ricerca prende spunto da un più ampio ambito di indagine volto ad approfondire il tema delle condizioni abitative a Roma nel corso del Novecento. Per larghi tratti la storia postunitaria di Roma è stata caratterizzata da un deficit di spazi abitativi che talora ha assunto i caratteri di emergenza sociale, particolarmente acuta per i soggetti con minori capacità di spesa. Una delle conseguenze dell’insufficiente offerta di abitazioni per i ceti più popolari fu il diffondersi di insediamenti informali, baraccopoli composte da alloggi che rispondevano agli elementari bisogni abitativi di immigrati e famiglie già residenti. Tali presenze, in diverse aree della città ben percepibili fino all’inizio degli anni Ottanta, furono oggetto delle attenzioni delle autorità locali che in più occasioni provvidero a censire i baraccati. Quei censimenti forniscono dati utili alla comprensione del fenomeno ma molti aspetti restano da approfondire. A questo riguardo, un’opportunità viene offerta dalla documentazione conservata presso l’Archivio Storico Capitolino, tra la quale figura anche l’intero corpus delle schede di rilevazione compilate in occasione del censimento dei baraccati del 1933. Si tratta di documenti riguardanti oltre 4.400 famiglie che contengono una considerevole mole di elementi analitici finora usati solo parzialmente. Attraverso la costruzione di un database che ne recepisca integralmente il potenziale informativo, l’uso di aggiornate metodologie statistiche e sistemi di georiferimento, rendono oggi possibile indagare con un inedito grado di dettaglio le caratteristiche demografiche, sociali ed economiche di coloro che abitavano le baraccopoli romane nei primi anni Trenta. La realizzazione della base di dati, è tuttora in corso – sono stati inseriti le informazioni relative a circa 1.500 schede, poco meno di un terzo del totale – ma alcune prime elaborazioni, sebbene parziali e provvisorie, lasciano già emergere nuovi ed interessanti spunti da valutare anche in chiave comparativa con quanto evidenziato dalle rilevazioni condotte dal dopoguerra

Bayesian estimate of population count with false captures: a latent class approach

We propose a capture–recapture model for estimating the size of a population based on multiple lists in presence of out-of-scope units (false captures). Our Bayesian approach makes use of a class of log–linear models with a latent structure. We also address the presence of sources providing partial information implementing a Gibbs Sampler algorithm which generates a sample from the posterior distribution of the population size in the presence of missing data. The proposed method is applied to simulated data sets

Population size estimation from incomplete multisource lists: A Bayesian perspective on latent class modelling

We propose a capture–recapture model for estimating the size of a population of interest based on a set of administrative sources and/or surveys in the presence of out-of-scope units (false captures). Our Bayesian approach makes use of a certain class of log - linear models with a latent structure. We also address the presence of sources providing partial information implementing a Gibbs Sampler algorithm which generates from the posterior distribution of the population size in presence of missing data. The proposed method is applied to simulated data set