Quickly and accurately perform Z-Test calculations using your Z-Score and the direction of your hypothesis test (one-sided or two-sided). Ideal for researchers, students, and statisticians needing immediate insights into their data analysis.
Z‑Test Calculator
Calculate the p‑value from a given z‑score.
* Enter the z‑score and select whether the test is one‑tailed or two‑tailed.
Step 1: Enter Z‑Score and Test Type
e.g., 1.96
Select one-tailed or two-tailed test.
How to Use This Calculator:
- Enter your Z-Score: Input the calculated Z-Score from your data analysis.
- Select Test Side: Choose either:
- One-sided Test (direction-specific)
- Two-sided Test (direction-neutral)
- Click Calculate: Obtain instant results for statistical significance.
Example Calculation:
If your Z-Score is 1.96 and you select a two-sided test, the calculator will quickly provide the associated p-value, indicating significance at typical alpha levels (e.g., α = 0.05).
Frequently Asked Questions:
- What is a Z-Test? A Z-Test checks for statistical significance between a sample mean and a known population mean, assuming the population variance is known.
- When should I use a one-sided vs. two-sided test? Use a one-sided test for directional hypotheses (greater than or less than). Use a two-sided test when testing for any difference without direction.
- Why is Z-Score important in a Z-Test? The Z-Score measures how many standard deviations the sample mean differs from the population mean, directly influencing significance.
Understanding Results:
- P-value: Represents the probability of observing your result if the null hypothesis is true. A lower p-value (usually ≤ 0.05) indicates significant results.
- Interpretation Guide: Clearly explains practical implications of significant or non-significant outcomes.
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