Selecting from a multi-indexed Series
The output of a single .groupby() operation on multiple columns is a Series with a MultiIndex. Working with this type of object is similar to working with a DataFrame:
- The outer index level is like the DataFrame rows.
- The inner index level is like the DataFrame columns.
In this exercise, you'll practice accessing data from a multi-indexed Series using the .loc[] accessor.
This exercise is part of the course
Analyzing Police Activity with pandas
Exercise instructions
- Save the output of the
.groupby()operation from the last exercise as a new object,arrest_rate. (This has been done for you.) - Print the
arrest_rateSeries and examine it. - Print the arrest rate for moving violations in bad weather.
- Print the arrest rates for speeding violations in all three weather conditions.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Save the output of the groupby operation from the last exercise
arrest_rate = ri_weather.groupby(['violation', 'rating']).is_arrested.mean()
# Print the 'arrest_rate' Series
print(____)
# Print the arrest rate for moving violations in bad weather
print(____)
# Print the arrest rates for speeding violations in all three weather conditions
print(____)