association_rules metric difference between confidence and lift results

[mz3r0]

Hi, new to association rules here.

I was reading: https://rasbt.github.io/mlxtend/user_guide/frequent_patterns/association_rules/

When using either metric, the resulting dataframe has many columns, including 'confidence' and 'lift'.

I noticed that, for the same threshold, using either metric returns a different number of rules.

How does confidence and lift values in the metric parameter affect the results and why are there two columns with the same name in the resulting dataframe?