Effective Sample Size Calculator
Compute weight-based effective sample size, normalized weights and the largest normalized weight.
Open toolCalculate equal-cluster design effect, effective sample size and sample-size enlargement. Provide Equal cluster size m, Intracluster correlation ρ, Supplied sample size / SRS target to compute results directly in your browser. DEFF = 1+(m−1)ρ and must be positive. Effective n = nominal n/DEFF; enlarged target = supplied SRS target × DEFF. Equal cluster sizes are assumed; this page does not apply a formula for unequal clusters. Numeric output uses up to 12 significant digits; floating-point rounding can occur.
Enter the inputs, then select Calculate.
Result will appear here
The Design Effect Calculator evaluates Equal cluster size m, Intracluster correlation ρ, Supplied sample size / SRS target in client-side JavaScript using the deterministic rule below and updates the output panel immediately without uploading data to a server.
Calculate equal-cluster design effect, effective sample size and sample-size enlargement.
DEFF = 1+(m−1)ρ and must be positive. Effective n = nominal n/DEFF; enlarged target = supplied SRS target × DEFF. Equal cluster sizes are assumed; this page does not apply a formula for unequal clusters. Numeric output uses up to 12 significant digits; floating-point rounding can occur.
Review the input parameters, allowed value ranges, and worked reference cases for the Design Effect Calculator below before running your calculation.
| Parameter / Scenario | Default / Sample Value | Rule or Allowed Range | Output / Usage Note |
|---|---|---|---|
| Input: Equal cluster size m | 20 | Range: 1 to 1000000 | Required workspace parameter |
| Input: Intracluster correlation ρ | 0.05 | Range: -1 to 1 | Required workspace parameter |
| Input: Supplied sample size / SRS target | 1000 | Range: 1 to 1000000000 | Required workspace parameter |
| Worked Case 1: Baseline run (Equal cluster size m = 20) | Preloaded / test values | Calculate equal-cluster design effect, effective sample size and sample-size enlargement | Equal cluster size m = 20; Intracluster correlation ρ = 0.05; Supplied sample size / SRS target = 1000. Output: Equal-cluster design effect: 1.95; Effective sample size : 512.820512821; Sample-size multiplier: 1.95; Enlarged sample for supplied SRS target: 1950. |
| Worked Case 2: Comparison scenario (Comparison equal cluster size m check) | Preloaded / test values | Calculate equal-cluster design effect, effective sample size and sample-size enlargement | Equal cluster size m = 10; Intracluster correlation ρ = 0.1; Supplied sample size / SRS target = 100. Output: Equal-cluster design effect: 1.9; Effective sample size: 52.6315789474; Sample-size multiplier: 1.9; Enlarged sample for supplied SRS target: 190. |
Follow these three steps to configure Equal cluster size m, Intracluster correlation ρ, Supplied sample size / SRS target, verify unit and boundary rules, and export your Design Effect Calculator output.
DEFF = 1+(m−1)ρ and must be positive. Effective n = nominal n/DEFF; enlarged target = supplied SRS target × DEFF. Equal cluster sizes are assumed; this page does not apply a formula for unequal clusters. Numeric output uses up to 12 significant digits; floating-point rounding can occur.
Select Calculate, check the labelled result, then use Copy result or Download result.txt.
These concrete scenarios illustrate how the Design Effect Calculator processes baseline inputs, comparison checks, and boundary constraints.
Equal cluster size m = 20; Intracluster correlation ρ = 0.05; Supplied sample size / SRS target = 1000. Output: Equal-cluster design effect: 1.95; Effective sample size : 512.820512821; Sample-size multiplier: 1.95; Enlarged sample for supplied SRS target: 1950.
Equal cluster size m = 10; Intracluster correlation ρ = 0.1; Supplied sample size / SRS target = 100. Output: Equal-cluster design effect: 1.9; Effective sample size: 52.6315789474; Sample-size multiplier: 1.9; Enlarged sample for supplied SRS target: 190.
When solving for 'design effect calculator', verify that Equal cluster size m, Intracluster correlation ρ, Supplied sample size / SRS target use consistent units and stay within the documented scope: DEFF = 1+(m−1)ρ and must be positive. Effective n = nominal n/DEFF; enlarged target = supplied SRS target × DEFF. Equal cluster sizes are assumed; this page does not apply a formula for unequal clusters. Numeric output uses up to 12 significant digits; floating-point rounding can occur.
The output panel reports the exact result derived from Equal cluster size m, Intracluster correlation ρ, Supplied sample size / SRS target alongside any unit or formatting notes.
Every calculation follows the rule: Calculate equal-cluster design effect, effective sample size and sample-size enlargement. Because JavaScript uses IEEE 754 double-precision floating-point arithmetic, numeric outputs display up to 12 significant digits where applicable.
Always cross-check the displayed result against the scope note (DEFF = 1+(m−1)ρ and must be positive. Effective n = nominal n/DEFF; enlarged target = supplied SRS target × DEFF. Equal cluster sizes are assumed; this page does not apply a formula for unequal clusters. Numeric output uses up to 12 significant digits; floating-point rounding can occur) before applying the value to production specifications, financial models, or lab records.
Review these boundary constraints and validation rules before relying on the Design Effect Calculator output.
Operational scope: DEFF = 1+(m−1)ρ and must be positive. Effective n = nominal n/DEFF; enlarged target = supplied SRS target × DEFF. Equal cluster sizes are assumed; this page does not apply a formula for unequal clusters. Numeric output uses up to 12 significant digits; floating-point rounding can occur. Inputs that violate minimum/maximum bounds or required format rules are rejected with a clear diagnostic prompt.
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Compute weight-based effective sample size, normalized weights and the largest normalized weight.
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Open toolAnswers about using Design Effect Calculator and understanding its results.
The Design Effect Calculator applies the rule: Calculate equal-cluster design effect, effective sample size and sample-size enlargement. Enter Equal cluster size m, Intracluster correlation ρ, Supplied sample size / SRS target into the workspace and the tool computes the exact output in your browser.
Yes. Provide Equal cluster size m, Intracluster correlation ρ, Supplied sample size / SRS target using the documented units and format shown in the quick reference table above. Preloaded default values let you test the workflow immediately.
DEFF = 1+(m−1)ρ and must be positive. Effective n = nominal n/DEFF; enlarged target = supplied SRS target × DEFF. Equal cluster sizes are assumed; this page does not apply a formula for unequal clusters. Numeric output uses up to 12 significant digits; floating-point rounding can occur. Confirm that your inputs fall within the allowed ranges before exporting the result.
Yes. All calculations for the Design Effect Calculator execute 100% locally in your browser's JavaScript runtime. No inputs or results are uploaded to any external server.
Choose another tool for your next calculation, conversion, or text task.