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One and Two Sample Test of Hypothesis

Statistical Decision: - Very often is practice; we are called upon to make decisions about population on the basic of sample information; such decisions are called Statistical Decision.

Statistical Hypothesis: - Such assumptions about the population may or may not be true are called Statistical Hypothesis.

Null Hypothesis: - If we want to decide whether one assumption or procedure is letter than another. Null Hypothesis is the positive rejection of Hypothesis. It is defined as Ho.

Alternative Hypothesis: - The Alternative Hypothesis is the logical opposite to the Null Hypothesis. It is defined as Ha.

One Tail Test: - A test of any Statistical Hypothesis where the alternative is one sided such as

Ho : μ = μo or Ho : μ = μo

Ha : μ > μo or Ha : μ < μo

Is called one Sided Test.

Two Tailed Test: A test of any Statistical Hypothesis where the alternative is two sided such as

Ho : μ = μo

Ha : μ ≠ μo

Is called Two Sided Test.

A test of the mean of a normal distribution against two sided alternative:

A test of the mean of a normal distribution against right sided alternative:

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