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Code to the article "Analyzing Longitudinal Multirater Data with Individually Varying Time Intervals"

Proceeding of: 55th Asilomar Conference on Signals, Systems, and Computers, October 31 - November 3, 2021 Pacific Grove, California, USA. In the emerging Internet of Things, a massive number of devices may connect to one common receiver. Consequently, models that study this setting are variants of the classical multiple-access channel where the number of users grows with the blocklength. Roughly, these models can be classified into three groups based on two criteria: the notion of probability of error and whether users use the same codebook. The first group follows the classical notion of probability of error and assumes that users use different codebooks. In the second group, users use different codebooks, but a new notion of probability of error called per-user probability of error is considered. The third group considers the per-user probability of error and that users are restricted to use the same codebook. This group is also known as unsourced random access. For the first and second groups of models, scaling laws that describe the capacity per unit-energy as a function of the order of growth of users were characterized by Ravi and Koch (arxiv.org/abs/2012.10350). In this paper, we first review these results. We then present scaling laws for the third group of models, i.e., unsourced random access. J. Ravi and T. Koch have received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant No. 714161). T. Koch has further received funding from the Spanish Ministerio de Ciencia e Innovación under Grant PID2020-116683GB-C21 / AEI / 10.13039/501100011033.

Additional file 1: Fig. S1. Diagram of the unified metadata model, depicting the coupling between the underlying models and the cardinality relationship between metadata entities. (A) The hierarchical metadata model used by qPortal to describe the experimental design of a research project, containing general information of sample biology. (B) The hierarchical metadata model used by OMERO, focused on describing imaging data. Fig. S2. The file size distribution of the synthetic project and benchmark test. (A) The distribution of file sizes for the synthetic project per modality. The X-ray CT data was sampled from the LiTS [19] training dataset (130 tomograms), the H&E stained histology images were sampled from the training dataset of MoNuSeg [20] (30 images), and the genomics dataset was obtained from the 1000 genomes project [21] (260 paired-end illumina whole genome sequencing datasets). (B) Results of the benchmarking test for data registration, showing sequential registration times for imaging data (x-ray CT and histology images) and genomics sequencing data (WGS) for an increasing number of patients, where data for a single patient consists of 1 x-ray CT, 20 histology images, and 4 fastq files (paired-end data for cancer and healthy tissue, respectively). The curves follow the mean values of 4 registration runs (black dots).

We propose a saddlepoint approximation of the error probability of a binary hypothesis test between two i.i.d. distributions. The approximation is accurate, simple to compute, and yields a unified analysis in different asymptotic regimes. The proposed formulation is used to efficiently compute the meta-converse lower bound for moderate block-lengths in several cases of interest. This work has been funded in part by the European Research Council (ERC) under grants 714161 and 725411, by the Spanish Ministry of Economy and Competitiveness under grants TEC2013-41718-R, RYC-201416332, IJCI-2015-27020 and TEC2016-78434-C3 (AEI/FEDER, EU), by the Madrid Autonomous Community under grant S2103/ICE-2845 and by the Spanish Ministry of Education, Culture and Sport under grant FPU14/01274.

Additional file 1: Table S1. Fit indices for a multiple-group CFAs of the six-item scale for different levels of measurement invariance.

We derive a lower bound on the smallest output entropy that can be achieved via vector quantization of a $d$-dimensional source with given expected $r$th-power distortion. Specialized to the one-dimensional case, and in the limit of vanishing distortion, this lower bound converges to the output entropy achieved by a uniform quantizer, thereby recovering the result by Gish and Pierce that uniform quantizers are asymptotically optimal as the allowed distortion tends to zero. Our lower bound holds for all $d$-dimensional memoryless sources having finite differential entropy and whose integer part has finite entropy. In contrast to Gish and Pierce, we do not require any additional constraints on the continuity or decay of the source probability density function. For one-dimensional sources, the derivation of the lower bound reveals a necessary condition for a sequence of quantizers to be asymptotically optimal as the allowed distortion tends to zero. This condition implies that any sequence of asymptotically-optimal almost-regular quantizers must converge to a uniform quantizer as the allowed distortion tends to zero., Comment: 26 pages, 1 figure. Submitted to IEEE Transactions on Information Theory. Most important changes with respect to previous version: i) changed title (the old title was "Rate-distortion bounds for high-resolution vector quantization via Gibbs's inequality"); ii) added necessary conditions for a sequence of quantizers to be asymptotically optimal (Theorem 7 and Corollary 8)

We study channel capacity when a one-bit quantizer is employed at the output of the discrete-time average-power-limited Rayleigh-fading channel. We focus on the low signal-to-noise ratio regime, where communication at very low spectral efficiencies takes place, as in Spread Spectrum and Ultra-Wideband communications. We demonstrate that, in this regime, the best one-bit quantizer does not reduce the asymptotic capacity of the coherent channel, but it does reduce that of the noncoherent channel., Comment: 4 pages. To be presented at the 2012 International Zurich Seminar on Communications (IZS)

This paper studies on-chip communication with non-ideal heat sinks. A channel model is proposed where the variance of the additive noise depends on the weighted sum of the past channel input powers. It is shown that, depending on the weights, the capacity can be either bounded or unbounded in the input power. A necessary condition and a sufficient condition for the capacity to be bounded are presented., to be presented at 2007 IEEE Information Theory Workshop (ITW), replaced with version that will appear in the proceedings

China has had an enormous growth of energy and electricity consumption during the last decades. This has been fuelled primarily by using domestic coal resources. Until 1997, annual construction of power stations averaged around 15 GW which was not sufficient to alleviate the demand surplus. Forecasts envisaged continuation of this growth. The majority of power stations is small scale and reather inefficient. Local air pollution is becoming very strong and is increasingly seen as a politi-cal issue. Foreign investment in the power sector has been hampered by bureaucracy and unclear competencies. On the demand side, energy efficiency has improved markedly in the last two dec-ades, albeit from a very low basis. Due to the economic transformation, many proven incentives for efficiency improvement cannot be used any more. The Clean Development Mechanism (CDM) opens a host of possibilities to link foreign investment in the energy supply and demand sectors with projects that enhance efficiency and reduce greenhouse gas emissions. All big industrial countries have been very keen on climate policy coop-eration with China. While the official Chinese negotiation position towards the CDM and climate policy in general has been extremely cautious, many government bodies show great interest. The Asian financial crisis, which led to an electricity oversupply in 1998, gives the possibility to retire the most inefficient power plants.

Currently, international climate negotiations concentrate on design issues for the flexible instruments outlined in the Kyoto Protocol. As the 6th Conference of the Parties to the U.N. Framework Convention on Climate Change in late 2000 or early 2001 has to take decisions on these matters, it is imperative to develop solutions that combine long-term economic efficiency with long-term environmental effectiveness. Sometimes, a reconciliation of these targets is difficult and compromises have to be made. This report discusses solutions for three critical issues which have got different degrees of attention until now but are linked inasmuch their solution will be crucial for the success of the Kyoto Protocol. The authors have come across them due to their close involvement in the negotiation process. The first issue has been a major topic of debate - the possibility that Russia and other countries in transition may have an enormous surplus of emission permits due to their economic collapse. Unfettered trade in this surplus would artificially depress permit prices, reduce the incentive for long-term innovation and would not be linked to any efficiency improvement in the selling countries. Koch and Michaelowa discuss ways how incentives can be devised to link sales of emission permits with actions that lead to long-term emission reductions. They include an element of early action designed to prevent lock-in on an emission-intensive path of economic recovery by fostering investments whose emission reduction cannot be quantified but is nevertheless real. Early project-related Joint Implementation plays an important role in this context. The second issue is relatively technical but a necessary condition for the functioning of a global market in emission permits. It deals with the design of a system of national registries that track trades in permits. An International Registry would be the node of this system and guarantee that no fraudulent trades enter the system. A homogenous trading unit would be created. The way how trades are processed, the information requirements and the time-related aspect of the implementation of the registry system are discussed. Finally, the third issue seems remote but may prove challenging in the long term. International conflict will impact upon the Kyoto Protocol commitments. Wars like the one in Kosovo will lead to additional greenhouse gas emissions that have to be accounted for. Territorial changes will lead to changes in commitments. The authors discuss the different possibilities that change commitments and make recommendations how they could be accommodated in the Kyoto framework. Dr. Axel Michaelowa, a former staff member of HWWA Institute for Economic Research, is now working as an independent climate policy expert in Paris. Among other functions, he serves as a permanent advisor and project coordinator for HWWA on the economics of international climate policy. Tobias Koch is a specialist on Russian climate and energy policy. He is doing research with the Center for Energy Policy in Moscow and has also worked for the UN climate change secretariat on issues of emissions trading. However, the views expressed in this report are his personal ones.

Ultra reliable low latency communication (URLLC) is an important feature in future mobile communication systems, as they will require high data rates, large system capacity and massive device connectivity [11]. To meet such stringent requirements, many error-correction codes (ECC)s are being investigated; turbo codes, low density parity check (LDPC) codes, polar codes and convolutional codes [70, 92, 38], among many others. In this work, we present generalized low density parity check (GLDPC) codes as a promising candidate for URLLC. Our proposal is based on a novel class of GLDPC code ensembles, for which new analysis tools are proposed. We analyze the trade-o_ between coding rate and asymptotic performance of a class of GLDPC codes constructed by including a certain fraction of generalized constraint (GC) nodes in the graph. To incorporate both bounded distance (BD) and maximum likelihood (ML) decoding at GC nodes into our analysis without resorting to multi-edge type of degree distribution (DD)s, we propose the probabilistic peeling decoding (P-PD) algorithm, which models the decoding step at every GC node as an instance of a Bernoulli random variable with a successful decoding probability that depends on both the GC block code as well as its decoding algorithm. The P-PD asymptotic performance over the BEC can be efficiently predicted using standard techniques for LDPC codes such as Density evolution (DE) or the differential equation method. We demonstrate that the simulated P-PD performance accurately predicts the actual performance of the GLPDC code under ML decoding at GC nodes. We illustrate our analysis for GLDPC code ensembles with regular and irregular DDs. This design methodology is applied to construct practical codes for URLLC. To this end, we incorporate to our analysis the use of quasi-cyclic (QC) structures, to mitigate the code error floor and facilitate the code very large scale integration (VLSI) implementation. Furthermore, for the additive white Gaussian noise (AWGN) channel, we analyze the complexity and performance of the message passing decoder with various update rules (including standard full-precision sum product and min-sum algorithms) and quantization schemes. The block error rate (BLER) performance of the proposed GLDPC codes, combined with a complementary outer code, is shown to outperform a variety of state-of-the-art codes, for URLLC, including LDPC codes, polar codes, turbo codes and convolutional codes, at similar complexity rates. Programa Oficial de Doctorado en Multimedia y Comunicaciones Presidente: Juan José Murillo Fuentes.- Secretario: Matilde Pilar Sánchez Fernández.- Vocal: Javier Valls Coquillat