Systematic Random Sampling:
This method is usually used in those cases where a complete list of the population from which the sample has to be drawn is available.
Under this method the Kth item is picked up from the sample frame and k is the sampling interval defined as: K=N/n Where, N is the size of the population and n is the size of the sample.
Example: If 2000 items are to be selected from a universe of 2,000 items the k will be 10. Now if the starting number is say 6 then the Kth numbers will be 16th, 26th, 36th etc. It is therefore, necessary to select the starting point carefully either by drawing a card from a well shuffled pack of cards or by throwing a dice or by taking out a number chit from a lot of 10 numbers or so.
This method is usually used in those cases where a complete list of the population from which the sample has to be drawn is available.
Under this method the Kth item is picked up from the sample frame and k is the sampling interval defined as: K=N/n Where, N is the size of the population and n is the size of the sample.
Example: If 2000 items are to be selected from a universe of 2,000 items the k will be 10. Now if the starting number is say 6 then the Kth numbers will be 16th, 26th, 36th etc. It is therefore, necessary to select the starting point carefully either by drawing a card from a well shuffled pack of cards or by throwing a dice or by taking out a number chit from a lot of 10 numbers or so.
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