simple random sampling by statisticalaid.com

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Uncomplicated random sampling

Simple random sampling is considered the easiest and most pop method of probability sampling. To perform simple random sampling, all a researcher must do is ensure that all members of the population are included in a main list, and that subjects are then selected randomly from this master list.

While simple random sampling creates samples that are highly representative of the population, it tin be fourth dimension consuming and tedious when creating large samples.

The following 8-step procedure may exist followed in cartoon a elementary random sample of north units from a population of North units.

  •     Assign serial numbers to the units in the population from 1 through Northward.
  •      Decide on the random number table to exist used.
  •      Cull an North-digit random number from any point in the random number tabular array.
  •      If this random number is less than or equal to N, this is your commencement selected unit.
  •      Move on to the next random number not exceeding N, vertically, horizontally or in whatever other direction systematically and choose your 2d unit.
  •      If at whatsoever stage of your choice, the random number chosen exceeds Northward, discard it and choose the adjacent random number.
  •      If, farther, whatsoever random number is repeated, it must too be discarded and be replaced by a fresh random number actualization side by side.
  •      The process stops one time you lot arrive at your desired sample size.

In that location are two approaches that aim to minimize any biases in the process of unproblematic random sampling:

  • Methods of lottery
  • Random number table method

Application of simple random sampling

  •      A list of all members of population is prepared. Each element is marked with a specific number (suppose from 1 toDue north).
  • due northitems are chosen among a population size ofN.This can be done either with the use of random number tables or random number generator software.
  •      The Effluvious Company is planning to carry a study to estimate the proportion of toilet soap users who prefer a certain color or flavor of their product. A unproblematic random sample of customers may be used for this purpose. It is assumed in this example that a listing (sampling frame) of the consumers is available to the research team.
  •      A forester in Chittagong Hill Tracts may wish to judge the volume of timber or proportion of diseased trees in a forest by se geographic points in the surface area covered by the forest and then attaching a plot of fixed size and shape to that point. All the trees inside the sample plots may be studied. But over again the basic design is a simple random sample.

Advantages of Simple Random Sampling

  • Information technology is a fair method of sampling and if applied appropriately information technology helps to reduce any bias involved as compared to whatsoever other sampling method involved.
  • Since it involves a large sample frame information technology is unremarkably easy to pick smaller sample size from the existing larger population.
  • The person who is conducting the enquiry doesn't need to have a prior knowledge of the data being collected. One tin simply ask a question to gather the researcher need not be a subject expert.
  • This sampling method is a very basic method of collecting the data. There is no technical cognition required and demand basic listening and recording skills….(more)

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