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Pandas provides the .corr() method which can be used to calculate the correlation between two columns in a DataFrame. This method returns a correlation value between -1 and 1, which indicates the strength of the relationship between the two columns. The closer the correlation value is to 1 or -1, the stronger the relationship between the two columns. The .corr() method can be used with any numerical data in Pandas.

You can use the following syntax to calculate the correlation between two columns in a pandas DataFrame:

df['column1'].corr(df['column2'])

The following examples show how to use this syntax in practice.

**Example 1: Calculate Correlation Between Two Columns**

The following code shows how to calculate the correlation between columns in a pandas DataFrame:

import pandas as pd #create DataFrame df = pd.DataFrame({'points': [25, 12, 15, 14, 19, 23, 25, 29], 'assists': [5, 7, 7, 9, 12, 9, 9, 4], 'rebounds': [11, 8, 10, 6, 6, 5, 9, 12]}) #view first five rows of DataFrame df.head() points assists rebounds 0 25 5 11 1 12 7 8 2 15 7 10 3 14 9 6 4 19 12 6 #calculate correlation between points and assists df['points'].corr(df['assists']) -0.359384

The correlation coefficient is **-0.359**. Since this correlation is negative, it tells us that points and assists are negatively correlated.

In other words, as values in the points column increase, the values in the assists column tend to decrease.

**Example 2: Calculate Significance of Correlation**

To determine whether or not a correlation coefficient is statistically significant, you can use the **pearsonr(x, y)** function from the library.

The following code shows how to use this function in practice:

import pandas as pd from scipy.stats import pearsonr #create DataFrame df = pd.DataFrame({'points': [25, 12, 15, 14, 19, 23, 25, 29], 'assists': [5, 7, 7, 9, 12, 9, 9, 4], 'rebounds': [11, 8, 10, 6, 6, 5, 9, 12]}) #calculate p-value of correlation coefficient between points and assists pearsonr(df['points'], df['assists']) (-0.359384, 0.38192)

The first value in the output displays the correlation coefficient (-0.359384) and the second value displays the p-value (0.38192) associated with this correlation coefficient.

Since the is not less than α = 0.05, we would conclude that the correlation between points and assists is not statistically significant.