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  2. Systematic sampling - Wikipedia

    en.wikipedia.org/wiki/Systematic_sampling

    In survey methodology, one-dimensional systematic sampling is a statistical method involving the selection of elements from an ordered sampling frame. The most common form of systematic sampling is an equiprobability method. [ 1 ]

  3. Simple random sample - Wikipedia

    en.wikipedia.org/wiki/Simple_random_sample

    If a systematic pattern is introduced into random sampling, it is referred to as "systematic (random) sampling". An example would be if the students in the school had numbers attached to their names ranging from 0001 to 1000, and we chose a random starting point, e.g. 0533, and then picked every 10th name thereafter to give us our sample of 100 ...

  4. Sampling (statistics) - Wikipedia

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

    A visual representation of the sampling process. In statistics, quality assurance, and survey methodology, sampling is the selection of a subset or a statistical sample (termed sample for short) of individuals from within a statistical population to estimate characteristics of the whole population. The subset is meant to reflect the whole ...

  5. Design effect - Wikipedia

    en.wikipedia.org/wiki/Design_effect

    Where is the sample size, = / is the fraction of the sample from the population, () is the (squared) finite population correction (FPC), is the unbiassed sample variance, and (¯) is some estimator of the variance of the mean under the sampling design. The issue with the above formula is that it is extremely rare to be able to directly estimate ...

  6. Line plot survey - Wikipedia

    en.wikipedia.org/wiki/Line_plot_survey

    Line plot survey is a systematic sampling technique used on land surfaces for laying out sample plots within a rectangular grid to conduct forest inventory or agricultural research. It is a specific type of systematic sampling , similar to other statistical sampling methods such as random sampling , but more straightforward to carry out in ...

  7. Stratified sampling - Wikipedia

    en.wikipedia.org/wiki/Stratified_sampling

    Proportionate allocation uses a sampling fraction in each of the strata that are proportional to that of the total population. For instance, if the population consists of n total individuals, m of which are male and f female (and where m + f = n), then the relative size of the two samples (x 1 = m/n males, x 2 = f/n females) should reflect this proportion.

  8. Forest inventory - Wikipedia

    en.wikipedia.org/wiki/Forest_inventory

    This grid will have preassigned plot areas to be sampled. It means more efficient logistics and removes some of the human bias that may be there with simple random sampling. Systematic stratified sampling: The most common type [citation needed] of inventory is one that uses a stratified random sampling technique. In includes first grouping by ...

  9. Probability-proportional-to-size sampling - Wikipedia

    en.wikipedia.org/wiki/Probability-proportional...

    The pps sampling results in a fixed sample size n (as opposed to Poisson sampling which is similar but results in a random sample size with expectancy of n). When selecting items with replacement the selection procedure is to just draw one item at a time (like getting n draws from a multinomial distribution with N elements, each with their own ...