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Bharath Prasad
Bharath Prasad

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Parametric vs Nonparametric Tests: Which One Should You Use for Your Data?

When working with data, one of the first questions you’ll face is: What kind of statistical test should I use? The answer often lies between a parametric and non parametric test—two fundamental approaches to data analysis.

Parametric tests (like t-tests and ANOVA) are powerful and precise. They assume your data is normally distributed, has equal variances, and is measured on an interval or ratio scale. When those assumptions are met, parametric tests deliver strong, reliable results.

But let’s face it—real-world data isn’t always that neat. That’s where nonparametric tests come in. These are your flexible, assumption-light alternatives. Whether your data is skewed, ordinal, or doesn’t meet normality, nonparametric methods like the Mann-Whitney U or Kruskal-Wallis test step up to the challenge.

So what’s the difference between parametric and non parametric test methods? Simply put: parametric tests require structure but offer more power, while nonparametric tests work on a broader range of data types but may be slightly less precise.

TL;DR:
Use parametric tests if your data is clean, normal, and continuous.

Use nonparametric tests if your data is messy, ordinal, or doesn’t follow assumptions.

Choosing the right one = more accurate insights.

Understanding these tests is essential for developers, data analysts, and researchers. Make sure your next analysis starts on the right foot.

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