What is the difference between mean and median?

Mean is the average (sum/count), while median is the middle value. Median is more resistant to outliers. For symmetric data they're similar; for skewed data they differ significantly.

What does IQR tell me?

The Interquartile Range (IQR) spans the middle 50% of your data. It's robust to outliers and used to identify them: values below Q1-1.5×IQR or above Q3+1.5×IQR are typically considered outliers.

How do I identify outliers?

Lower bound: Q1 - 1.5 × IQR. Upper bound: Q3 + 1.5 × IQR. Any data point outside these bounds is a potential outlier.

What is the five-number summary?

A concise data description using: minimum, Q1, median, Q3, and maximum. These five numbers provide a quick understanding of data distribution, center, and spread.

Why is standard deviation important?

Standard deviation quantifies data variability. In a normal distribution, ~68% of data falls within 1 std dev of the mean, ~95% within 2, and ~99.7% within 3.

Descriptive Statistics Calculator

Free descriptive statistics calculator. Analyze your data with 12 key metrics including mean, median, quartiles, IQR, variance, and standard deviation for comprehensive data exploration.

Get complete statistical summary: min, max, mean, median, mode, quartiles, variance, and standard deviation.

Mean = \frac{\sum x _{i}}{n}, Variance = \frac{\sum ( x _{i} - μ ) ^{2}}{n}, IQR = Q_{3} - Q_{1}

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