Читать книгу Informatics and Machine Learning. From Martingales to Metaheuristics онлайн

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Log‐normal distributions are used in geology and mining, medicine, environment, atmospheric science, and so on, where skewed distribution occurrences are very common. In Geology, the concentration of elements and their radioactivity in the Earth's crust are often shown to be log‐normal distributed. The infection latent period, the time from being infected to disease symptoms occurs, is often modeled as a log‐normal distribution. In the environment, the distribution of particles, chemicals, and organisms is often log‐normal distributed. Many atmospheric physical and chemical properties obey the log‐normal distribution. The density of bacteria population often follows the log‐normal distribution law. In linguistics, the number of letters per words and the number of words per sentence fit the log‐normal distribution. The length distribution for introns, in particular, has very strong support in an extended heavy‐tail region, likewise for the length distribution on exons or open reading frames (ORFs) in genomic deoxyribonucleic acid (DNA). The anomalously long‐tailed aspect of the ORF‐length distribution is the key distinguishing feature of this distribution, and has been the key attribute used by biologists using ORF finders to identify likely protein‐coding regions in genomic DNA since the early days of (manual) gene structure identification.