# Plot Graphs - Pearson's Correlation Coefficient Calculator

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This little calculator helps you to investigate if two data series are linearly correlated. It calculates the correlation coefficient according to Pearson in just a single click. Just fill the two colums with your data and press "calculate". If the two colums do not have the same length the values exceeding the length of the shorter column will be skipped. The correlation coefficient here is calculated according the definition given by Pearson:
`r = (1/n sum_{i=0}^{n} (x_i-bar(x))*(y_i-bar(y)) ) / (sqrt(1/n sum_{i=0}^{n} (x_i-bar(x))^2)*sqrt(1/n sum_{i=0}^{n} (y_i-bar(y))^2) )`

## Pearson's Correlation Coefficient

- A correlation coefficient > 0 means a positive correlation
- A correlation coefficient < 0 means a anti-correlation

More about the statistical interpretation of the correlation coefficient...

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