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The Normal (Gaussian) Distribution
Formula
The normal distribution, also known as the Gaussian distribution or bell curve, is the most important probability distribution in statistics. It is defined by two parameters: the mean and the standard deviation.
Approximately 68% of values fall within one standard deviation of the mean, 95% within two, and 99.7% within three, known as the 68-95-99.7 rule.
Common use cases:
- Standardized test scoring
- Quality control process limits
- Financial risk modeling
Frequently Asked Questions
Maria Gonzalez
Registered Dietitian, RD, MPH
Maria is a Registered Dietitian with a Master's in Public Health. She focuses on evidence-based nutrition assessment tools including BMI, calorie calculations, and body composition analysis.
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