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

    The table shown on the right can be used in a two-sample t-test to estimate the sample sizes of an experimental group and a control group that are of equal size, that is, the total number of individuals in the trial is twice that of the number given, and the desired significance level is 0.05. [4]

  3. Sampling (statistics) - Wikipedia

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

    Formulas, tables, and power function charts are well known approaches to determine sample size. Steps for using sample size tables: Postulate the effect size of interest, α, and β. Check sample size table [20] Select the table corresponding to the selected α; Locate the row corresponding to the desired power; Locate the column corresponding ...

  4. Descriptive statistics - Wikipedia

    en.wikipedia.org/wiki/Descriptive_statistics

    For example, in papers reporting on human subjects, typically a table is included giving the overall sample size, sample sizes in important subgroups (e.g., for each treatment or exposure group), and demographic or clinical characteristics such as the average age, the proportion of subjects of each sex, the proportion of subjects with related ...

  5. Data collection - Wikipedia

    en.wikipedia.org/wiki/Data_collection

    Data collection or data gathering is the process of gathering and measuring information on targeted variables in an established system, which then enables one to answer relevant questions and evaluate outcomes. Data collection is a research component in all study fields, including physical and social sciences, humanities, [2] and business ...

  6. Theoretical sampling - Wikipedia

    en.wikipedia.org/wiki/Theoretical_sampling

    Flexibility occurs in this style of sampling when the researchers want to increase the sample size due to new factors that arise during the research. Flexibility also occurs when the researcher's wishes to use a small sample during the initial stages of the research but increase the sample size to test developing generalizations.

  7. Systematic sampling - Wikipedia

    en.wikipedia.org/wiki/Systematic_sampling

    where n is the sample size, and N is the population size. Using this procedure each element in the population has a known and equal probability of selection (also known as epsem). This makes systematic sampling functionally similar to simple random sampling (SRS). However, it is not the same as SRS because not every possible sample of a certain ...

  8. Data analysis - Wikipedia

    en.wikipedia.org/wiki/Data_analysis

    Data analysis is a process for obtaining raw data, and subsequently converting it into information useful for decision-making by users. [1] Data is collected and analyzed to answer questions, test hypotheses, or disprove theories. [11] Statistician John Tukey, defined data analysis in 1961, as:

  9. Survey sampling - Wikipedia

    en.wikipedia.org/wiki/Survey_sampling

    Quota Samples: The sample is designed to include a designated number of people with certain specified characteristics. For example, 100 coffee drinkers. This type of sampling is common in non-probability market research surveys. Convenience Samples: The sample is composed of whatever persons can be most easily accessed to fill out the survey.