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Topic Review
Gompertz Function with R
The Gompertz function is a sigmoid curve being a special case of a logistic curve. Although it was originally designed to describe mortality, it is now used in biology. For example, it is useful to describe many  phenomena such as the growth of a cancerous tumor confined to an organ without metastasis, the growth of the number of individuals in a population, e.g. prey in a Volterra-Lotka model, the germination of seeds, etc. It also models as the logistic function the growth of a colony of bacteria or in an epidemic the spread of the number of infected people. However, despite its many applications, in many cases the fitting of experimental data to the Gompertz function is not always straightforward. In this article we present a protocol that will be useful when performing the data regression to this curve using the statistical package R.
  • 20.1K
  • 07 Apr 2021
Topic Review
Forensic Statistics
Forensic statistics is the application of probability models and statistical techniques to scientific evidence, such as DNA evidence, and the law. In contrast to "everyday" statistics, to not engender bias or unduly draw conclusions, forensic statisticians report likelihoods as likelihood ratios (LR). This ratio of probabilities is then used by juries or judges to draw inferences or conclusions and decide legal matters. Jurors and judges rely on the strength of a DNA match, given by statistics, to make conclusions and determine guilt or innocence in legal matters. In forensic science, the DNA evidence received for DNA profiling often contains a mixture of more than one person's DNA. DNA profiles are generated using a set procedure, however, the interpretation of a DNA profile becomes more complicated when the sample contains a mixture of DNA. Regardless of the number of contributors to the forensic sample, statistics and probabilities must be used to provide weight to the evidence and to describe what the results of the DNA evidence mean. In a single-source DNA profile, the statistic used is termed a random match probability (RMP). RMPs can also be used in certain situations to describe the results of the interpretation of a DNA mixture. Other statistical tools to describe DNA mixture profiles include likelihood ratios (LR) and combined probability of inclusion (CPI), also known as random man not excluded (RMNE). Computer programs have been implemented with forensic DNA statistics for assessing the biological relationships between two or more people. Forensic science uses several approaches for DNA statistics with computer programs such as; match probability, exclusion probability, likelihood ratios, Bayesian approaches, and paternity and kinship testing. Although the precise origin of this term remains unclear, it is apparent that the term was used in the 1980s and 1990s. Among the first forensic statistics conferences were two held in 1991 and 1993.
  • 2.2K
  • 12 Oct 2022
Topic Review
Extreme values statistic
One of the pillars of experimental sciences is sampling. Based on analysis conducted on samples the estimations for the populations are made. The distributions are split in two main groups: continuous and discrete and the present study applies for the continuous ones. One of the challenges of the sampling is the accuracy of it, or, in other words how representative is the sample for the population from which was drawn. Another challenge, connected with this one, is the presence of the outliers - observations wrongly collected, not actually belonging to the population subjected to study. The present study proposes a statistic (and a test) intended to be used for any continuous distribution to detect the outliers, by constructing the confidence interval for the extreme value in the sample, at certain (preselected) risk of being in error, and depending on the sample size. The proposed statistic is operational for known distributions (having known their probability density function) and is dependent too on the statistical parameters of the population.
  • 1.1K
  • 29 Oct 2020
Topic Review
Digital Marketing Utilization Index in Digital Marketing Capability
The digital marketing utilization index (DMUI) measures an organization’s ability to utilize digital marketing to create value for the company through the utilization of the readiness of the innovation ecosystem, digital marketing technology, and digital transformation.
  • 1.7K
  • 06 Sep 2022
Topic Review
Diffusion of Solar PV Energy
Solar photovoltaic energy (solar PV) is considered a very attractive solution among renewable energy sources (RES), especially for households. According to the most recent IEA report on renewables, the growth of renewable power capacity at the world level has reached another record in 2021, driven by solar photovoltaic energy; solar PV alone has accounted for more than half of all renewable power expansion in 2021, followed by wind and hydropower.
  • 1.0K
  • 28 Apr 2022
Topic Review
Data Mining in Agriculture
Data mining in agriculture is a recent research topic, consisting of the application of data mining techniques to agriculture. Recent technologies are able to provide extensive information on agricultural-related activities, which can then be analyzed in order to find relevant information. A related, but not equivalent term is precision agriculture.
  • 777
  • 18 Nov 2022
Topic Review
Data Analysis/4 Data Mining
Data mining (sometimes called knowledge discovery) is the process of analyzing and summarizing data into useful information which can be used to understand common features, the origin of data and to extract hidden predictive information. Data mining is used in science, engineering, modeling and analysis of financial markets.
  • 392
  • 15 Nov 2022
Topic Review
CT for Double Lung and Colorectal Cancer Screening
Annual screening of lung cancer (LC) with chest low-dose computed tomography (CT) and screening of colorectal cancer (CRC) with CT colonography every 5 years are recommended by the United States Prevention Service Task Force. 
  • 191
  • 20 Oct 2022
Topic Review
Consensus Big Data Clustering for Bayesian Mixture Models
In the context of big-data analysis, the clustering technique holds significant importance for the effective categorization and organization of extensive datasets. However, pinpointing the ideal number of clusters and handling high-dimensional data can be challenging. To tackle these issues, several strategies have been suggested, such as a consensus clustering ensemble that yields more significant outcomes compared to individual models. Another valuable technique for cluster analysis is Bayesian mixture modelling, which is known for its adaptability in determining cluster numbers. 
  • 177
  • 18 Aug 2023
Topic Review
Chi square statistic
The Chi-Square test is based on a series of assumptions frequently used in the statistical analysis of experimental data. The main weakness of the chi-square test is that is very accurate only in convergence (in large size samples), and for small sample sizes is exposed to errors of both types (type I and type II). On two scenarios of use - goodness of fit and contingencies assessment (2x2 tables of contingency) - here are discussed different aspects involving it. Further knowledge on the regard of the type of the error in contingencies assessment push further the analysis of the data, while in the same time opens the opportunity to devise a method for filling the gaps in contingencies (e.g. censored data), both scenarios being discussed here in detail. A program designed to fill the gaps in the assumption of the association is provided.
  • 3.6K
  • 24 Dec 2020
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