Statistics Basics
Fundamental statistical measures and concepts.
The data
0
- Measure
- Mean (Average)
- Description
- Sum of all values divided by count.
- Formula
- xbar = Sum(xi) / n
1
- Measure
- Median
- Description
- Middle value when data is sorted. Robust to outliers.
- Formula
- Middle element (or avg of two)
2
- Measure
- Mode
- Description
- Most frequently occurring value in the dataset.
- Formula
- argmax frequency
3
- Measure
- Variance
- Description
- Average squared deviation from the mean.
- Formula
- sigma2 = Sum(xi - xbar)2 / n
4
- Measure
- Standard Deviation
- Description
- Square root of variance; measures spread in original units.
- Formula
- sigma = sqrt(variance)
5
- Measure
- Correlation
- Description
- Measure of linear relationship between two variables.
- Formula
- r = Cov(X,Y) / (sigma_x * sigma_y)
6
- Measure
- Z-Score
- Description
- Number of standard deviations a value is from the mean.
- Formula
- z = (x - xbar) / sigma
Fetch the same bytes
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curl "https://yjtoon.com/api/dataset/statistics-basics?format=toon"
const res = await fetch( "https://yjtoon.com/static-data/dataset/statistics-basics.toon" ); const toon = await res.text();
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