Sampling according to Slovin's formula if the population size is large
When selecting a sample
when the population size is large. For example country population, state
population, or village population. Such a large population cannot be included
directly in the research. So a group representing this population is called a
sample. We intend to include this sample in research, but we face many
difficulties in selecting a sample from a large population. Primarily some
people visit 5%, 10% of the sample
population. Or they determine the sample size from the population as a percentage.
But even if this method is used, it is necessary to select the sample in a
scientific manner. For this, we need to select the sample using some statistical
techniques. If we select a sample based on these statistical techniques, the
sample is considered to be representative of the population. For this, we will
see how to use Slovin's formula
Example -
18000 farmers
are members of Sahyadri Agro Farm. How many farmers will be included in the
sample? Based on Slovin's formula method, the sample selection is done as
follows.
|
Slovin's formula - n = N / (1+Ne2)
n: sample size required N: population size e: Acceptable margin of
error (0.05) |
n = N / (1+Ne2) n = 18000
/ (1+18000(0.05)2) n = 18000
/ (18001(0.0025) n = 18000
/ 45.0025 n = 399.98 n = 400 |
From this out of 18000 farmers in Sahyadri Agro Farm 400 farmers will be selected as samples.