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Hypothesis Testing

Null vs Alternative

Rejection region and significance level

Type I error vs type II error

Test for the mean. Population variance known

p-value

Test for the mean. Population variance unknown

Test for the mean. Dependent samples

Test for the mean. Independent samples (Part1)

Test for the mean. Independent samples (Part2)

Scientific Method​

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Hypotheses​

  • A hypothesis is "an idea that can be tested"
  • It is a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation

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Examples of hypotheses​

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Decisions you can take​

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Level of significance and types of tests​

  • Level of significance (α) - The probability of rejecting a null hypothesis that is true; the probability of making this error.

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Statistical errors (Type I and Type II Error)​

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P-value​

  • The p-value is the smallest level of significance at which we can still reject the null hypothesis, given the observed sample statistic

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Formulae for Hypothesis Testing​

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