plot

The plot module provides users with Python only implementations of common electoral plots.

A novel addition to social science analysis is the disproportionality bar plot, which graphically depicts the disproportionality between expected and realized results. Bar widths are the proportion of shares (ex: votes received), and heights are the difference or relative difference between shares and allocations (ex: parliament seats received).

Functions

• poli_sci_kit.plot.dispr_bar()

• poli_sci_kit.plot.parliament()

• poli_sci_kit.utils.gen_parl_points()

• poli_sci_kit.utils.swap_parl_allocations()

poli_sci_kit.plot.dispr_bar(shares, allocations, labels=None, colors=None, total_shares=None, total_alloc=None, percent=False, dsat=0.95, axis=None)

Plots the difference in allocated seats to received shares.

Parameters:

shareslist

The shares amounts or those that allocations should be compared to.

allocationslist

The allocated amounts.

labelslist (default=None)

A list of group names as labels for the x-axis.

colorslist or list of listsoptional (default=None)

The colors of the groups as hex keys.

total_sharesint (default=None)

The total share amounts.

Note: allows for subsets of the total groups.

total_allocint (default=None)

The total number of allocations amounts.

Note: allows for subsets of the total groups.

percentbool (default=False)

Whether the y-axis should depict relative changes or not.

dsatfloatoptional (default=default_sat)

The degree of desaturation to be applied to the colors.

axisstroptional (default=None)

Adds an axis to plots so they can be combined.

Returns:

axmatplotlib.pyplot.subplot

A bar plot with aggregate or relative seat-share differences and bar widths representing share proportions.

poli_sci_kit also provides Python only implementations of both rectangular and semicircle parliament plots:

poli_sci_kit.plot.parliament(allocations, labels=None, colors=None, style='semicircle', num_rows=2, marker_size=200, speaker=False, df_seat_lctns=None, dsat=0.95, axis=None, legend=False, **kwargs)

Produces a parliament plot given seat allocations.

Parameters:

allocationslist

The share of seats given to the regions or parties.

labelslist (contains strs)optional (default=None)

The names of the groups.

colorslistoptional (default=None)

The colors of the groups as hex keys.

stylestr (default=semicircle)

Whether to plot the parliament as a semicircle or a rectangle.

num_rowsint (default=2)

The number of rows in the plot.

marker_sizeint or float (default=200)

The size of the scatterplot markers that make up the plot.

speakerbooloptional (default=False)

Whether to include a point for the speaker of the house colored by their group.

Note: ‘True’ colors the point based on the largest group, but passing a name from ‘labels’ is also possible.

df_seat_lctnsdfoptional (default=None)

A df of coordinates to plot.

dsatfloatoptional (default=default_sat)

The degree of desaturation to be applied to the colors.

axisstroptional (default=None)

Adds an axis to plots so they can be combined.

Returns:

axmatplotlib.pyplot.subplot

Parliament seat distribution as either an arc or a rectangle, each having the option to be converted to seats.

The parliament plot function is built on top of scatter plots that are derived in the package’s utils module:

poli_sci_kit.utils.gen_parl_points(allocations, labels=None, style='semicircle', num_rows=2, speaker=False)

Produces a df with coordinates for a parliament plot.

Parameters:

allocationslist

The share of seats given to the regions or parties.

labelslistoptional (default=None)

The names of the groups.

stylestr (default=semicircle)

Whether to plot the parliament as a semicircle or a rectangle.

num_rowsint (default=2)

The number of rows in the plot.

speakerbooloptional (default=False)

Whether to include a point for the speaker of the house colored by their group.

Note: ‘True’ colors the point based on the largest group, but passing a name from ‘labels’ is also possible.

Returns:

df_seat_lctnspd.DataFrame

A dataframe with points to be converted to a parliament plot via seaborn’s scatterplot.

A final function to swap poorly allocated seats is also provided in utils:

poli_sci_kit.utils.swap_parl_allocations(df, row_0, pos_0, row_1, pos_1)

Replaces two allocations of the parliament plot df to clean up coloration.

Parameters:

dfpandas.DataFrame

DataFrame containing parliament data

row_0int

The row of one seat to swap.

pos_0int

The position in the row of one seat to swap.

row_1int

The row of the other seat to swap.

pos_1int

The position in the row of the other seat to swap.

Returns:

df_seat_lctnspd.DataFrame

A parliament plot allocations data frame with two allocations swapped