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  2. Z-test - Wikipedia

    en.wikipedia.org/wiki/Z-test

    This test leverages the property that the sample proportions (which is the average of observations coming from a Bernoulli distribution) are asymptotically normal under the Central Limit Theorem, enabling the construction of a z-test. The z-statistic for comparing two proportions is computed using: = ^ ^ ^ (^) (+) Where: ^ = sample proportion ...

  3. Test statistic - Wikipedia

    en.wikipedia.org/wiki/Test_statistic

    Test statistic is a quantity derived from the sample for statistical hypothesis testing. [1] A hypothesis test is typically specified in terms of a test statistic, considered as a numerical summary of a data-set that reduces the data to one value that can be used to perform the hypothesis test.

  4. p-chart - Wikipedia

    en.wikipedia.org/wiki/P-chart

    In statistical quality control, the p-chart is a type of control chart used to monitor the proportion of nonconforming units in a sample, where the sample proportion nonconforming is defined as the ratio of the number of nonconforming units to the sample size, n. [1] The p-chart only accommodates "pass"/"fail"-type inspection as determined by ...

  5. Standard normal table - Wikipedia

    en.wikipedia.org/wiki/Standard_normal_table

    gives a probability that a statistic is greater than Z. This equates to the area of the distribution above Z. Example: Find Prob(Z ≥ 0.69). Since this is the portion of the area above Z, the proportion that is greater than Z is found by subtracting Z from 1. That is Prob(Z ≥ 0.69) = 1 − Prob(Z ≤ 0.69) or {{{1}}}.

  6. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    The sample size is an important feature of any empirical study in which the goal is to make inferences about a population from a sample. In practice, the sample size used in a study is usually determined based on the cost, time, or convenience of collecting the data, and the need for it to offer sufficient statistical power. In complex studies ...

  7. Ionic strength - Wikipedia

    en.wikipedia.org/wiki/Ionic_strength

    The molar ionic strength, I, of a solution is a function of the concentration of all ions present in that solution. [3]= = where one half is because we are including both cations and anions, c i is the molar concentration of ion i (M, mol/L), z i is the charge number of that ion, and the sum is taken over all ions in the solution.

  8. Charge number - Wikipedia

    en.wikipedia.org/wiki/Charge_number

    Atomic numbers (Z) are a special case of charge numbers, referring to the charge number of an atomic nucleus, as opposed to the net charge of an atom or ion. The charge numbers for ions (and also subatomic particles ) are written in superscript, e.g., Na + is a sodium ion with charge number positive one (an electric charge of one elementary ...

  9. Normalization (statistics) - Wikipedia

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

    In statistics and applications of statistics, normalization can have a range of meanings. [1] In the simplest cases, normalization of ratings means adjusting values measured on different scales to a notionally common scale, often prior to averaging.