Miracle-dz/UniFAR-FTUs huggingface dataset:
CHAIN LADDER AND ERROR PROPAGATION

Abstract We show how estimators for the chain ladder prediction error in Mack's (1993) distribution-free stochastic model can be derived using the error propagation formula. Our method allows for the treatment of the general case of the prediction error of the loss development result between two arbitrary future horizons. In the well-known special cases considered previously by Mack (1993) and Merz and Wüthrich (2008), our estimators coincide with theirs. However, the algebraic form in which we cast them is new, considerably more compact and more intuitive to understand. For example, in the classical case treated by Mack (1993), we show that the mean squared prediction error divided by the squared estimated ultimate loss can be written as ∑jû2j, where ûj measures the (relative) uncertainty around the jth development factor and the proportion of the estimated ultimate loss that it affects. The error propagation method also provides a natural split into process error and parameter error. Our proofs identify and exploit symmetries of “chain ladder processes” in a novel way. For the sake of wider practical applicability of the formulae derived, we allow for incomplete historical data and the exclusion of outliers in the triangles.
Status and Projection Estimates of Agricultural Implements and Machinery in India

It is an accepted fact that higher levels of production in agriculture need higher levels of power availability. In the absence of adequate power supply, agricultural operations cannot be completed in time and yields would be adversely affected. Availability of adequate farm power is very crucial for timely farm operations for increasing production and productivity and handling the crop produce to reduce losses. With the increase in intensity of cropping the turnaround time is drastically reduced and it is not possible to harvest and thresh the standing crop, on one hand, and prepare seed bed and do timely sowing operations of subsequent crop, on the other hand, in the limited time available, unless adequate farm power is available. As such there is a strong need for more authentic figures relating to the items pertaining to agricultural implements and machinery. In the changing scenario, it has became more important to have projection estimates of total number of tractors, power tillers, diesel engines, electric pumps and other power-operated agricultural machinery and implements for the future years. Making use of available yearly data, the projected population of agricultural machinery and implements for future years at All-India level has been worked out in this paper.
Non-parametric determination of H and He interstellar fluxes from cosmic-ray data

Top-of-atmosphere (TOA) cosmic-ray (CR) fluxes from satellites and balloon-borne experiments are snapshots of the solar activity imprinted on the interstellar (IS) fluxes. Given a series of snapshots, the unknown IS flux shape and the level of modulation (for each snapshot) can be recovered. We wish (i) to provide the most accurate determination of the IS H and He fluxes from TOA data alone, (ii) to obtain the associated modulation levels (and uncertainties) while fully accounting for the correlations with the IS flux uncertainties, and (iii) to inspect whether the minimal force-field approximation is sufficient to explain all the data at hand. Using H and He TOA measurements, including the recent high-precision AMS, BESS-Polar, and PAMELA data, we performed a non-parametric fit of the IS fluxes $J^{\rm IS}_{\rm H,~He}$ and modulation level $\phi_i$ for each data-taking period. We relied on a Markov chain Monte Carlo (MCMC) engine to extract the probability density function and correlations (hence the credible intervals) of the sought parameters. Although H and He are the most abundant and best measured CR species, several datasets had to be excluded from the analysis because of inconsistencies with other measurements. From the subset of data passing our consistency cut, we provide ready-to-use best-fit and credible intervals for the H and He IS fluxes from MeV/n to PeV/n energy (with a relative precision in the range [2-10\%] at 1$\sigma$). Given the strong correlation between $J^{\rm IS}$ and $\phi_i$ parameters, the uncertainties on $J^{\rm IS}$ translate into $\Delta\phi\approx \pm 30$~MV (at 1$\sigma$) for all experiments. We also find that the presence of $^3$He in He data biases $\phi$ towards higher $\phi$ values by $\sim 30$~MV. The force-field approximation gives an excellent ($\chi^2/$dof$=1.02$) description of the recent high-precision TOA H and He fluxes.
A Simple Panel‐CADF Test for Unit Roots

In this paper we propose a simple extension to the panel case of the covariate-augmented Dickey Fuller (CADF) test for unit roots developed in Hansen (1995). The extension we propose is based on a p-values combination approach that takes into account cross-section dependence. We show that the test is easy to compute, has good size properties and gives power gains with respect to other popular panel approaches. A procedure to compute the asymptotic p-values of Hansen’s CADF test is also a side-contribution of the paper. We also complement Hansen (1995) and Caporale and Pittis (1999) with some new theoretical results. Two empirical applications are carried out for illustration purposes on international data to test the PPP hypothesis and the presence of a unit root in international industrial production indices.
RESAMPLING PROCEDURES TO COMPARE TWO SURVIVAL DISTRIBUTIONS IN THE PRESENCE OF RIGHT-CENSORED DATA

SUMMARY In this simulation study, the accuracy of the size of four classes of test procedures asymptotic normal test, permutation test, bootstrap hypothesis test, and bootstrap interval test were compared using the logrank and Prentice-Wilcoxon two sample test statistics. Sample sizes of 20 and 50 per group were used. Twenty observations per group yielded differences in the test procedures. When the Prentice-Wilcoxon test statistic was employed, the asymptotic test procedure was the most accurate; resampling procedures did not improve upon its accuracy. Using the logrank test statistic, the permutation or bootstrap hypothesis testing procedures were closest to the nominal significance level. The more popular asymptotic normal logrank test was consistently anticonservative. When the number of observations in each group was increased to 50, the test procedures were comparable. Power comparisons were also examined. The test with the greatest power was dependent upon the two survival patterns and the choice of test statistic.
Inquiring about Loss Aversion of Achievement Value

According to the achievement motivation theory, in achievement context, students may have to not only approach success/gain (e.g., strive to get a better grade) but also avoid failure/loss (e.g., avoid performing worse). However, these two types of achievement motivation have often been investigated separately. In contrast, loss aversion, a central argument in prospect theory, posits that avoiding losses has a greater impact on preferences than does approaching gains; suggesting that gain approach and loss avoidance should be treated as asymmetric forces that can be analyzed simultaneously to study approach to gain and avoidance to loss among students in terms of grades. The main purposes of this study were to propose an alternative measure to frame the dynamic evaluation process in the context of achievement that considers students’ sensitivity to performance change, and to further investigate students’ loss aversion in relation to grades through intrapersonal and interpersonal comparisons. A total of 41 and 72 college students participated in study 1 and study 2, respectively. One-way repeated measure ANOVA was conducted for the former sample while the single sample t-tests and independent sample ANOVA were used for the latter. Through the implementation of this alternative measure, the results revealed that (1) college students were more sensitive to performance changes than to their current or final performance, and (2) loss aversion was dependent on the referents. Students were averse to interpersonal loss, but not to intrapersonal loss. These findings indicate the usefulness of the proposed measure for investigating the asymmetric responses between two types of achievement motivation, and the proposed measure can be used to extend and revise the explanatory boundaries of prospect theory and self-discrepancy theory.
Group music therapy for people living with mental health conditions in the community: A pilot longitudinal quantitative micro-analysis study

ABSTRACT Introduction Music therapy has growing evidence for its effectiveness in mental health. People with mental health conditions often face significant barriers in obtaining personal valued social roles and feeling a sense of belonging to their community. Overcoming these barriers is an important step in the recovery process. This pilot study investigated whether long-term group music therapy might have an impact on participants’ social skill development, group cohesion and expression of emotional states. Method The study was an exploratory, retrospective, quantitative, longitudinal single-case study (N = 8). Five video recorded sessions were selected and micro-analyzed by independent raters, who rated the Group Environmental Scale (n = 8) and Individual Behavior Observation Categorization scale (n = 4). Statistical analysis was carried out to identify trends over time. The study was registered in ClinicalTrials.gov (NCT04435405). Results A longitudinal improvement was found in the group domains of Relationship (1.6-fold), Personal growth (1.9-fold) and System maintenance (1.5-fold) along the 9-month follow-up period. On the individual level, an improvement was found over time in social skills and group cohesion (4.85-fold), affect (3.15-fold), and musical activities performances (19.9-fold). Discussion The study demonstrated longitudinal improvement trends in social skills, group cohesion and expression of emotional states (affect) in the group as a whole and in each of the four individual assessments. Future studies which will include a larger sample and longer follow-up periods are needed.
Maximum Likelihood Estimation for Contingency Tables and Logistic Regression with Incorrectly Linked Data

Data linkage is the act of bringing together records that are believed to belong to the same unit ( e.g. , person or business) from two or more files. It is a very common way to enhance dimensions such as time and breadth or depth of detail. Data linkage is often not an error-free process and can lead to linking a pair of records that do not belong to the same unit. There is an explosion of record linkage applications, yet there has been little work on assuring the quality of analyses using such linked files. Naively treating such a linked file as if it were linked without errors will, in general, lead to biased estimates. This paper develops a maximum likelihood estimator for contingency tables and logistic regression with incorrectly linked records. The estimation technique is simple and is implemented using the well-known EM algorithm. A well known method of linking records in the present context is probabilistic data linking. The paper demonstrates the effectiveness of the proposed estimators in an empirical study which uses probabilistic data linkage.
Phase Matching in Microstructured Lithium Niobate on Insulator Waveguides

The recent development of the Lithium Niobate on Insulator (LNOI) fabrication process has opened a bright future for integrating ultra-compact photonic circuits. Due to its excellent nonlinear properties, as a waveguide material, Lithium Niobate supports nonlinear optical processes including efficient sum frequency generation and second harmonic generation. To enhance these effects, precise control of mode confinement and modal phase matching is required. In this work, we engineer an LNOI waveguide to match the effective refractive indices of the fundamental mode, TE00 at the fundamental wavelength and second-order mode, TE20 at the second harmonic wavelength. As waveguide geometry plays an essential role, optimization of waveguide parameters is crucial for the design of high-performance, feasible devices. Here, we numerically engineer and characterize the influence of rib waveguide geometry parameters including etching depth, <inline-formula> <tex-math notation="LaTeX">$D$ </tex-math></inline-formula>, width, <inline-formula> <tex-math notation="LaTeX">$W$ </tex-math></inline-formula> and sidewall angle, <inline-formula> <tex-math notation="LaTeX">$\theta $ </tex-math></inline-formula> on the phase matching condition. We find that the waveguide phase matching condition is most susceptible to variations in the sidewall angle. For the optimized parameter values of <inline-formula> <tex-math notation="LaTeX">$\{D,\theta \} = \{450\,\mathrm {nm}, 10^{o}\}$ </tex-math></inline-formula>, the phase-matching wavelength tunability is achieved through the waveguide width control.
Rate, Power, and Energy Efficiency Trade-Offs in Massive MIMO Systems With Carrier Aggregation

This work considers a multi-cell, multi-carrier massive MIMO network with carrier aggregation capabilities, and tackles both the rate versus power consumption and the rate versus energy efficiency (EE) trade-offs, by jointly optimizing the number of employed carriers, transmit antennas, base station density, and transmit power. Provably convergent algorithms for both trade-off problems are developed, together with closed-form results for the individual optimization of the considered resources, taking three main carrier aggregation techniques into account, namely inter-carrier, intra-carrier contiguous, and intra-carrier non-contiguous. Numerical results show how the use of carrier aggregation represents an effective way of increasing the network rate and EE, while keeping the power consumption at bay. By using carrier aggregation, it is possible to reduce the number of deployed antennas, without sacrificing the rate performance and increasing the system EE.
The Free Product of Two Groups with a Malnormal Amalgamated Subgroup

In [1], B. Baumslag defined a subgroup U of a group G to be malnormal in G if gug –1 ∈ U, 1 ≠ u ∈ U, implies that g ∈ U. Baumslag considered the class of amalgamated products (A * B; U) in which U is malnormal in both A and B. These amalgamated products play an important role in the investigations of B. B. Newman [13] of groups with one defining relation having torsion. In this paper, we shall be concerned primarily with a generalization of this class. Let U be a subgroup of a group G and let u ∈ U. Then the extended normalizer EG(u, U) of u relative to U in G is defined by if u ≠ 1, and by EG(u, U) = U if u = 1.
Revealing the sources and sinks of negative cluster ions in an urban environment through quantitative analysis

Abstract. Atmospheric cluster ions are important constituents in the atmosphere, and their concentrations and compositions govern their role in atmospheric chemistry. However, there is currently limited quantitative research on atmospheric ion compositions, sources, and sinks, especially in the urban atmosphere where pollution levels and human populations are intense. In this study, we measured the compositions of negative cluster ions and neutral molecules using an atmospheric pressure interface high-resolution time-of-flight mass spectrometer (APi-TOF) and a chemical ionization mass spectrometer in urban Beijing. Quantitative analysis of cluster ions was performed by their comparison with condensation sink (CS), reagent ions, and neutral molecules. We demonstrate the feasibility of quantifying cluster ions with different compositions using in situ-measured ion mobility distributions from a neutral cluster and air ion spectrometer (NAIS). The median concentration of negative cluster ions was 85 (61–112 for 25 %–75 %) cm−3 during the measurement period, which was negatively correlated with CS. The negative cluster ions mainly consisted of inorganic nitrogen-containing ions, inorganic sulfur-containing ions, and organic ions in the form of adducts with NO3- or HSO4-. The CHON-related organic ions accounted for over 70 % of the total organic ions. Although the molecules clustered with NO3- and HSO4- had similar compositions, we found that HSO4- clustered more efficiently with CHO and CHONnonNPs species (CHON excluding nitrated phenols), while NO3- clustered more efficiently with nitrated phenols (CHONNPs). Additionally, most organic ions were positively correlated with neutral molecules, resulting in similar diurnal cycles of organic ions and neutral molecules. However, an exception was found for CHONNPs, the concentration of which is also significantly influenced by the reagent ions NO3-. The charge fractions are generally higher for molecules with higher molecular weight and a higher oxidation state, and the opposite diurnal variations in charging fractions between H2SO4 and organic species indicate a charging competition between them. Finally, we choose HSO4- and C3H3O4- as representatives to calculate the contribution of different formation and loss pathways. We found their losses are condensational loss onto aerosol particles (73 %–75 %), ion–molecule reaction losses (19 %), and ion–ion recombination losses (6 %–8 %).
Identifying the Soybean microRNAs Related to Phytophthora sojae Based on RNA Sequencing and Bioinformatics Analysis

Phytophthora root rot in soybeans is caused by a pathogen called Phytophthora sojae (P. sojae), which results in a significant decrease in soybean production within affected regions. MicroRNAs (miRNAs) are a class of small non-coding RNA molecules that play a key post-transcriptional regulatory role in eukaryotes. In this paper, the miRNAs that respond to P. sojae were analyzed from the gene level to complement the study of molecular resistance mechanisms in soybean. The study utilized high-throughput sequencing of soybean data to predict miRNAs that respond to P. sojae, analyze their specific functions, and verify regulatory relationships using qRT-PCR. The results showed that the miRNAs in soybean respond to P. sojae infection. MiRNAs can be transcribed independently, suggesting the presence of transcription factor binding sites in the promoter regions. Additionally, we performed an evolutionary analysis on conserved miRNAs that respond to P. sojae. Finally, we investigated the regulatory relationships among miRNAs, genes, and transcription factors, and identified five regulatory patterns. These findings lay the groundwork for future studies on the evolution of miRNAs responsive to P. sojae.
The Boundedness of Commutators for the Marcinkiewicz Integrals

In this paper, the authors consider the boundedness of commutators for the Marcinkiewicz integral μΩb on Lp(Rn) and Hardy spaces, here Ω being a homogeneous function of degree zero on Rn and satisfying a class of Lq-Dini condition. The results in this paper are substantial improvements over some known results.
Multiscale feature analysis of forecast errors of 500 hPa geopotential height for the CMA‐GFS model

Using ERA5 reanalysis data from March 2021 to February 2022 and the China Meteorological Administration Global Forecasting System (CMA‐GFS) operational forecast dataset of 500 hPa geopotential height in the Northern Hemisphere in the same period, the multiscale features of forecast errors are analyzed. The results indicate that the anomaly correlation coefficient (ACC) of 500 hPa geopotential height and its multiscale components in the Northern Hemisphere keep decreasing with the extension of forecast lead time, and there are no seasonal differences in the evolution of the ACC. The effective forecast skills by season for the CMA‐GFS model are above 6 days at multiscale, with the highest skills in winter and the planetary‐scale components. In space, significant seasonal differences are observed in the locations of the extreme values of multiscale forecast errors for 500 hPa geopotential height, and the spatial distribution of forecast errors reflects the inadequate prediction of the intensity of large‐scale trough and ridge systems at middle and high latitudes and the phase‐shift prediction of small troughs and ridges at middle latitudes. Generally, the forecast errors of the original field and planetary‐scale component show wavelike or banded distribution, and the synoptic‐scale forecast errors are always distributed in latitudinal wavelike patterns alternating between positive and negative, without significant differences in the distribution of land, sea, and terrain. The first empirical orthogonal function modes of multiscale forecast errors almost retain their respective feature. In temporal, the spring, summer, and autumn time series all have quasi‐biweekly positive and negative phase transitions within the monthly scale, and the significant phase transition in winter only occurs around January 1st. These results deepen the understanding of the distribution and possible causes of forecast errors of the CMA‐GFS model and provide ideas for the improvement and revision of the model.
Collision, Coalescence and Breakup of Raindrops. Part I: Experimentally Established Coalescence Efficiencies and Fragment Size Distributions in Breakup

Abstract The collision, coalescence and breakup of single raindrop pairs were studied at terminal velocities and laboratory pressure (100 kPa) in 761 collision experiments (out of 14 000 attempts). Six size combinations were used with drop pair diameters of [0.18;. 0.0395 cm], [0.40; 0.0395 cm], [0.44; 0.0395 cm], [0.18; 0.0715 cm], [0.18; 0.10 cm] and [0.30; 0.10 cm]. For averaging purposes the experiments were repeated over one hundred times for each pair. The new coalescence efficiencies and fragment size distributions in breakup turned out to be consistent with those of McTaggart-Cowan and List (1975b) and permitted the combination of the two data sets into a single data bank spanning essentially the entire range of raindrop sizes. The analysis addressed three main geometric shapes formed by the drops after initial contact, namely, filaments, sheets and disks, and the fragment size distributions after breakup. Significant collisional growth, i.e., coalescence, occurred only when drops <0.06 cm in diame.
Multilayer External Enclosing Wall Structures with Air Gaps or Channels

Precise meanings of thermophysical processes taking place in air gaps have decisive importance in composite cladding structure systems’ calculation and modeling. The climatic load conditions in Kazakhstan can significantly affect the microclimate of premises in general. In this work, a review study is carried out to obtain the relevant scientific literature on enclosing structures with air gaps under various climatic conditions. The review mainly covers research institutes from Sweden, Norway, France, Saudi Arabia, Russia, and China. On the issue of the air gap parameter’s influence on thermophysical processes, 16 papers were analyzed, and on the issue of air infiltration, 12 papers were analyzed. However, the review shows a lack of research in this area under various climatic conditions. At the same time, experience has shown that the principle of multilayer protection from climatic influences creates a favorable microclimate in buildings, but due to a possible temperature drop, wall structures made of composite building materials can be quite favorable under some conditions, and under others they may be less favorable. Therefore, working out a new energy-saving design with air gaps for climatic conditions with large temperature fluctuations during summer and winter is an urgent task.