Mastering Statistical Inference and Testing

Decoding Hypothesis Testing: Methods and P-Values

Learning Outcome

6

Understand statistical vs practical significance

5

Explain Type I and Type II errors

4

Interpret test statistics and p-values

3

Understand significance level (α)

2

Differentiate null and alternative hypotheses

1

Define hypothesis testing

Lets recall...

We use sample variability to answer questions:

Hook/Story/Analogy(Slide 4)

We follow a structured approach to make evidence-based decisions

Let us understand each step clearly....

What is Hypothesis Testing?

Hypothesis testing is a structured method used to evaluate a claim about a population using sample data

It compares two competing statements:

The goal is not to prove something true

The goal is to test whether there is enough evidence to reject the null hypothesis

Step 1: State the Hypotheses

H₀

Null Hypothesis

No effect exists

No difference between groups

Status quo remains unchanged

Important:

Hypotheses must be stated before collecting data

Important:

Hypotheses must be stated before collecting data

Research claim

Effect or difference exists

Something has changed

Example

H₁: μ > 100 (one-tailed)
H₁: μ ≠ 100 (two-tailed)

Step 2: Set the Significance Level (α)

Step 3: Choose the Test

Step 4: Calculate the Test Statistic

Measures how far the sample mean is from the hypothesized population mean

Large distance relative to variability → Stronger evidence against H₀

Step 5: Find the P-Value

If H₀ is true, what is the probability of observing this result (or more extreme)?

Smaller p-value → Stronger evidence against H₀

Step 6: Make Statistical Decision

We never “accept” H₀ absolutely
 

We only decide whether evidence is strong enough to reject it

Statistical significance is not equal to Practical Importance

Step 7: Interpret in Context

Summary

5

Reject or fail to reject H₀ (consider Type I & II errors)

4

Test statistic and p-value measure evidence

3

α defines acceptable error risk

2

H₀: no effect; H₁: research claim

1

Hypothesis testing evaluates claims using sample data

Quiz

Null hypothesis usually represents:

A. Research claim

B. No effect

C. Large sample

D. True statement

Quiz-Answer

Null hypothesis usually represents:

A. Research claim

B. No effect

C. Large sample

D. True statement

Decoding Hypothesis Testing: Methods and P-Values

By Content ITV

Decoding Hypothesis Testing: Methods and P-Values

  • 13