Achieve the appropriate accuracy of results by design
Know whether your findings are truly significant or not
Sampling & Significance
Advice on sampling methods, including:
- Stratification
- Clustering
- Quotas
We can advise on minimum and optimum sample sizes required for the types of analysis and accuracies you desire.
We offer help with calculating true differences between findings (including locating the appropriate test)..
| Sample Size | 99% confidence | 95% confidence | 90% confidence |
200 |
+/- 8.96% |
+/- 6.86% |
+/- 5.78% |
300 |
+/- 7.35% |
+/- 5.62% |
+/- 4.73% |
500 |
+/- 5.72% |
+/- 4.37% |
+/- 3.67% |
1000 |
+/- 4.06% |
+/- 3.09% |
+/- 2.60% |
1500 |
+/- 3.32% |
+/- 2.53% |
+/- 2.12% |
2000 |
+/- 2.88% |
+/- 2.19% |
+/- 1.84% |