What happens when we do not know the standard deviation of a population? What is the impact on the formula? why?
When we don't know standard deviation then we have to use sample
standard deviation . The denominator changes from n to
n-1. Standard Deviation of sample = ((X -
X_{i})^{2}/(n-1))^{0.5} . The formula is
n-1 to factor in the degree of freedom.
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What happens when we do not know the standard deviation of a population? What is the...
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