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  2. Alternative abiogenesis scenarios - Wikipedia

    en.wikipedia.org/wiki/Alternative_abiogenesis...

    A scenario is a set of related concepts pertinent to the origin of life (abiogenesis), such as the iron-sulfur world. Many alternative abiogenesis scenarios have been proposed by scientists in a variety of fields from the 1950s onwards in an attempt to explain how the complex mechanisms of life could have come into existence. These include ...

  3. Pivot table - Wikipedia

    en.wikipedia.org/wiki/Pivot_table

    A pivot table is a table of values which are aggregations of groups of individual values from a more extensive table (such as from a database, spreadsheet, or business intelligence program) within one or more discrete categories. The aggregations or summaries of the groups of the individual terms might include sums, averages, counts, or other ...

  4. Pivotal quantity - Wikipedia

    en.wikipedia.org/wiki/Pivotal_quantity

    Then is called a pivotal quantity (or simply a pivot). Pivotal quantities are commonly used for normalization to allow data from different data sets to be compared. It is relatively easy to construct pivots for location and scale parameters: for the former we form differences so that location cancels, for the latter ratios so that scale cancels.

  5. Power Pivot - Wikipedia

    en.wikipedia.org/wiki/Power_Pivot

    Power Pivot allows for importing data from multiple sources, such as databases (SQL Server, Microsoft Access, etc.), OData data feeds, Excel files, and other sources, facilitating comprehensive data analysis within a single environment. [10] The VertiPaq compression engine is used to hold the data model in memory on the client computer ...

  6. Error threshold (evolution) - Wikipedia

    en.wikipedia.org/wiki/Error_threshold_(evolution)

    It can be seen that, for example, one third of the mutations of the [001] molecules will produce [000] molecules, while the other two thirds will produce the class 2 molecules [011] and [101]. We can now write the expression for the child populations n i ′ {\displaystyle n'_{i}} of class i in terms of the parent populations n j {\displaystyle ...

  7. Abiogenesis - Wikipedia

    en.wikipedia.org/wiki/Abiogenesis

    If the deep marine hydrothermal setting was the site for the origin of life, then abiogenesis could have happened as early as 4.0-4.2 Gya. If life evolved in the ocean at depths of more than ten meters, it would have been shielded both from impacts and the then high levels of ultraviolet radiation from the sun.

  8. Bootstrapping (statistics) - Wikipedia

    en.wikipedia.org/wiki/Bootstrapping_(statistics)

    Based on the assumption that the original data set is a realization of a random sample from a distribution of a specific parametric type, in this case a parametric model is fitted by parameter θ, often by maximum likelihood, and samples of random numbers are drawn from this fitted model. Usually the sample drawn has the same sample size as the ...

  9. Substitution model - Wikipedia

    en.wikipedia.org/wiki/Substitution_model

    In biology, a substitution model, also called models of sequence evolution, are Markov models that describe changes over evolutionary time. These models describe evolutionary changes in macromolecules, such as DNA sequences or protein sequences, that can be represented as sequence of symbols (e.g., A, C, G, and T in the case of DNA or the 20 "standard" proteinogenic amino acids in the case of ...