parametric statistical inference
DESCRIPTION
PARAMETRIC STATISTICAL INFERENCE. We are now going to test these statements Examine the likelihood (probability) that a suspected claim would occur if an existing claim were true What is the claim being challenged? What is the alternate claim? - PowerPoint PPT PresentationTRANSCRIPT
PARAMETRIC STATISTICAL INFERENCE
We are now going to test these statements
• Examine the likelihood (probability) that a suspected claim would occur if an existing claim were true
• What is the claim being challenged?• What is the alternate claim?
– If we get an outcome that would be unlikely if Ho were true and is in the direction suggested by Ha, we have evidence against Ho in favor of Ha.
– Make “unlikely” precise by calculating the probability that an alternate (suspected) event is observed assuming Ho to be true (default or existing claim is true)
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PARAMETRIC STATISTICAL INFERENCE
• The probability, computed assuming Ho is true, that the observed outcome would take a value as extreme or more extreme than that actually observed is called the P-VALUE of the test.
– The smaller the p-value the stronger is the evidence against Ho provided by the data.
1-SAMPLE Z STATISTIC FOR , known
• the test statistic assesses the evidence against the null hypothesis by allowing the calculation of p-value
• If the test statistic (Z-value) falls far from
the value suggested by the null hypothesis in the direction specified by the alternative hypothesis, it is good evidence against Ho and in favor of Ha.
P-value describes how strong the evidence is
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