enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    Sample size determination. Sample size determination or estimation is the act of choosing the number of observations or replicates to include in a statistical sample. 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 ...

  3. Standard error - Wikipedia

    en.wikipedia.org/wiki/Standard_error

    This approximate formula is for moderate to large sample sizes; the reference gives the exact formulas for any sample size, and can be applied to heavily autocorrelated time series like Wall Street stock quotes.

  4. Ordinary least squares - Wikipedia

    en.wikipedia.org/wiki/Ordinary_least_squares

    t. e. Okun's law in macroeconomics states that in an economy the GDP growth should depend linearly on the changes in the unemployment rate. Here the ordinary least squares method is used to construct the regression line describing this law. In statistics, ordinary least squares (OLS) is a type of linear least squares method for choosing the ...

  5. Design effect - Wikipedia

    en.wikipedia.org/wiki/Design_effect

    In survey methodology, the design effect (generally denoted as , , or ) is a measure of the expected impact of a sampling design on the variance of an estimator for some parameter of a population. It is calculated as the ratio of the variance of an estimator based on a sample from an (often) complex sampling design, to the variance of an ...

  6. Power (statistics) - Wikipedia

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

    According to this formula, the power increases with the values of the effect size and the sample size n, and reduces with increasing variability . In the trivial case of zero effect size, power is at a minimum ( infimum ) and equal to the significance level of the test α , {\displaystyle \alpha \,,} in this example 0.05.

  7. Ratio estimator - Wikipedia

    en.wikipedia.org/wiki/Ratio_estimator

    where n is the sample size and N is the population size and s xy is the ... The sample estimate was 71,866.333 baptisms per year over this period giving a ratio of ...

  8. Simple linear regression - Wikipedia

    en.wikipedia.org/wiki/Simple_linear_regression

    However, those formulas do not tell us how precise the estimates are, i.e., how much the estimators ^ and ^ vary from sample to sample for the specified sample size. Confidence intervals were devised to give a plausible set of values to the estimates one might have if one repeated the experiment a very large number of times.

  9. Margin of error - Wikipedia

    en.wikipedia.org/wiki/Margin_of_error

    Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Donate; Help; Learn to edit; Community portal; Recent changes; Upload file