Describe The 8 Steps In The Hypothesis Testing Proces 977969

Describe the 8 steps in the process for hypothesis testing Explain the decision criteria for rejecting the null hypothesis for both the p value method and the critical value method

Describe the 8 steps in the process for hypothesis testing. Explain the decision criteria for rejecting the null hypothesis for both the p-value method and the critical value method.

Hypothesis testing is a fundamental process in statistics that allows researchers to make inferences about a population parameter based on sample data. The process involves systematically evaluating a claim or assumption regarding a population characteristic, such as the mean or proportion. The eight key steps in hypothesis testing provide a structured approach to this evaluation, ensuring rigor and clarity in decision-making.

1. State the hypotheses in words: Begin by clearly articulating the research question or claim. This involves framing the null hypothesis (H₀), which represents the default or status quo assumption, and the alternative hypothesis (H₁), which reflects the research claim or what the researcher aims to support.

2. Translate hypotheses into symbols: Convert the verbal hypotheses into mathematical notation, typically involving parameters such as the population mean (μ) or proportion. For example, H₀: μ = 65,000 versus H₁: μ

3. Choose a significance level (α): Determine the threshold probability for making a Type I error — rejecting a true null hypothesis. Common choices include 0.05, 0.01, or 0.10, indicating a 5%, 1%, or 10% risk, respectively. The significance level defines how extreme the data must be to reject the null hypothesis.

4. Identify the rejection and acceptance regions: Based on α and the nature of the test (left-tailed, right-tailed, or two-tailed), find the critical values that demarcate rejection and non-rejection zones on the distribution curve used for testing.

5. Create the distribution curve and find the critical values: Graph the standard distribution (normal or t distribution) and mark the critical values. These are the cutoff points beyond which the null hypothesis will be rejected. For example, for α=0.05 in a left-tailed test, the critical z-value is approximately -1.96.

6. Calculate the test statistic: Use the sample data to compute the test statistic, which quantifies how far the observed sample mean (or proportion) is from the hypothesized population parameter, standardized by the standard error. For large sample sizes with known population variance, a Z-test is often used; otherwise, a t-test may be appropriate.

7. Make a decision based on the test statistic: Compare the calculated test statistic to the critical value. If it falls into the rejection region, reject H₀; otherwise, do not reject H₀. Alternatively, determine the p-value and compare it to α; if p-value ≤ α, reject H₀.

8. State the conclusion in words: Interpret the statistical decision in the context of the original research question. For example, “There is sufficient evidence at the 5% significance level to conclude that the average salary is less than $65,000,” or “We fail to reject the null hypothesis, and thus, we cannot conclude that the average salary differs from $65,000.”

Decision Criteria for Rejecting Null Hypothesis

When using the critical value method, rejection occurs if the test statistic exceeds the critical value in the tail(s) of the distribution. Specifically, for a left-tailed test, if Z critical value, reject H₀. For a two-tailed test at α=0.05, if |Z| > 1.96, reject H₀.

In the p-value method, reject the null hypothesis if the p-value is less than or equal to the significance level (p-value ≤ α). The p-value represents the probability of observing a test statistic as extreme or more extreme than the one calculated, assuming H₀ is true. A small p-value indicates strong evidence against H₀, prompting rejection.

Both methods lead to the same conclusion; the critical value approach focuses on cutoff points in the distribution, while the p-value approach assesses the extremeness of the observed data directly. The choice of method often depends on convenience and context in reporting results.

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