Tax-Calculator Utilities

Tax-Calculator Utilities

taxcalc.utils

PUBLIC low-level utility functions for Tax-Calculator.

taxcalc.utils.add_income_table_row_variable(dframe, income_measure, bin_edges)

Add a variable to specified Pandas DataFrame, dframe, that specifies the table row and is called ‘table_row’. The rows are defined by the specified bin_edges function argument. Note that the bin groupings are LEFT INCLUSIVE, which means that bin_edges=[1,2,3,4] implies these three bin groupings: [1,2), [2,3), [3,4).

Parameters:

• dframe (Pandas DataFrame) – the object to which we are adding bins

• income_measure (String) – specifies income variable used to construct bins

• bin_edges (list of scalar bin edges) –

Returns:

dframe – the original input plus the added ‘table_row’ column

Return type:

Pandas DataFrame

taxcalc.utils.add_quantile_table_row_variable(dframe, income_measure, num_quantiles, pop_quantiles=False, decile_details=False, weight_by_income_measure=False)

Add a variable to specified Pandas DataFrame, dframe, that specifies the table row and is called ‘table_row’.

When weight_by_income_measure=False, the rows hold an equal number of people if pop_quantiles=True or an equal number of filing units if pop_quantiles=False.

When weight_by_income_measure=True, the rows hold an equal number of income dollars.

This function assumes that specified dframe contains columns for the specified income_measure and for sample weights, s006, and when pop_quantiles=True, number of exemptions, XTOT.

. When num_quantiles is 10 and decile_details is True,

the bottom decile is broken up into three subgroups (neg, zero, and pos income_measure) and the top decile is broken into three subgroups (90-95, 95-99, and top 1%).

taxcalc.utils.atr_graph_data(vdf, year, mars='ALL', atr_measure='combined', pop_quantiles=False)

Prepare average tax rate data needed by xtr_graph_plot utility function.

Parameters:

• vdf (a Pandas DataFrame object containing variables and tax liabilities) – (See Calculator.atr_graph method for required elements of vdf.)

• year (integer) – specifies calendar year of the data in vdf

• mars (integer or string) –

  specifies which filing status subgroup to show in the graph

  • ’ALL’: include all filing units in sample

  • 1: include only single filing units

  • 2: include only married-filing-jointly filing units

  • 3: include only married-filing-separately filing units

  • 4: include only head-of-household filing units

• atr_measure (string) –

  specifies which average tax rate to show on graph’s y axis

  • ’itax’: average individual income tax rate

  • ’ptax’: average payroll tax rate

  • ’combined’: sum of average income and payroll tax rates

• pop_quantiles (boolean) – specifies whether or not quantiles contain an equal number of people (True) or an equal number of filing units (False)

Return type:

dictionary object suitable for passing to xtr_graph_plot utility function

taxcalc.utils.bootstrap_se_ci(data, seed, num_samples, statistic, alpha)

Return bootstrap estimate of standard error of statistic and bootstrap estimate of 100*(1-2*alpha)% confidence interval for statistic in a dictionary along with specified seed and nun_samples (B) and alpha.

taxcalc.utils.ce_aftertax_expanded_income(df1, df2, custom_params=None, require_no_agg_tax_change=True)

Return dictionary that contains certainty-equivalent of the expected utility of after-tax expanded income computed for several constant-relative-risk-aversion parameter values for each of two Pandas DataFrame objects: df1, which represents the pre-reform situation, and df2, which represents the post-reform situation. Both DataFrame objects must contain ‘s006’, ‘combined’, and ‘expanded_income’ columns.

IMPORTANT NOTES: These normative welfare calculations are very simple. It is assumed that utility is a function of only consumption, and that consumption is equal to after-tax income. This means that any assumed responses that change work effort will not affect utility via the correpsonding change in leisure. And any saving response to changes in after-tax income do not affect consumption.

The cmin value is the consumption level below which marginal utility is considered to be constant. This allows the handling of filing units with very low or even negative after-tax expanded income in the expected-utility and certainty-equivalent calculations.

taxcalc.utils.certainty_equivalent(exputil, crra, cmin)

Calculate and return certainty-equivalent of exputil of consumption assuming an isoelastic utility function with crra and cmin as parameters.

Parameters:

• exputil (float) – expected utility value

• crra (non-negative float) – constant relative risk aversion parameter of isoelastic utility function

• cmin (positive float) – consumption level below which marginal utility is assumed to be constant

Return type:

certainty-equivalent of specified expected utility, exputil

taxcalc.utils.create_diagnostic_table(dframe_list, year_list)

Extract diagnostic table from list of Pandas DataFrame objects returned from a Calculator dataframe(DIST_VARIABLES) call for each year in the specified list of years.

Parameters:

• dframe_list (list of Pandas DataFrame objects containing the variables) –

• year_list (list of calendar years corresponding to the dframe_list) –

Return type:

Pandas DataFrame object containing the diagnostic table

taxcalc.utils.create_difference_table(vdf1, vdf2, groupby, tax_to_diff, pop_quantiles=False)

Get results from two different vdf, construct tax difference results, and return the difference statistics as a table.

Parameters:

• vdf1 (Pandas DataFrame including columns named in DIFF_VARIABLES list) – for example, object returned from a dataframe(DIFF_VARIABLES) call on the basesline Calculator object

• vdf2 (Pandas DataFrame including columns in the DIFF_VARIABLES list) – for example, object returned from a dataframe(DIFF_VARIABLES) call on the reform Calculator object

• groupby (String object) –

  options for input: ‘weighted_deciles’ or

  ’standard_income_bins’ or ‘soi_agi_bins’

  determines how the rows in the resulting Pandas DataFrame are sorted

• tax_to_diff (String object) – options for input: ‘iitax’, ‘payrolltax’, ‘combined’ specifies which tax to difference

• pop_quantiles (boolean) – specifies whether or not weighted_deciles contain an equal number of people (True) or an equal number of filing units (False)

Returns:

• difference table as a Pandas DataFrame with DIFF_TABLE_COLUMNS and

• groupby rows.

• NOTE (when groupby is ‘weighted_deciles’, the returned table has three) – extra rows containing top-decile detail consisting of statistics for the 0.90-0.95 quantile range (bottom half of top decile), for the 0.95-0.99 quantile range, and for the 0.99-1.00 quantile range (top one percent); and the returned table splits the bottom decile into filing units with negative (denoted by a 0-10n row label), zero (denoted by a 0-10z row label), and positive (denoted by a 0-10p row label) values of the specified income_measure.

taxcalc.utils.create_distribution_table(vdf, groupby, income_measure, pop_quantiles=False, scaling=True)

Get results from vdf, sort them by expanded_income based on groupby, and return them as a table.

Parameters:

• vdf (Pandas DataFrame including columns named in DIST_TABLE_COLUMNS list) – for example, an object returned from the distribution_table_dataframe function in the Calculator distribution_tables method

• groupby (String object) –

  options for input: ‘weighted_deciles’ or

  ’standard_income_bins’ or ‘soi_agi_bins’

  determines how the rows in the resulting Pandas DataFrame are sorted

• income_measure (String object) – options for input: ‘expanded_income’ or ‘expanded_income_baseline’ determines which variable is used to sort rows

• pop_quantiles (boolean) – specifies whether or not weighted_deciles contain an equal number of people (True) or an equal number of filing units (False)

• scaling (boolean) – specifies whether or not table entry values are scaled

Returns:

• distribution table as a Pandas DataFrame with DIST_TABLE_COLUMNS and

• groupby rows.

• NOTE (when groupby is ‘weighted_deciles’, the returned table has three) – extra rows containing top-decile detail consisting of statistics for the 0.90-0.95 quantile range (bottom half of top decile), for the 0.95-0.99 quantile range, and for the 0.99-1.00 quantile range (top one percent); and the returned table splits the bottom decile into filing units with negative (denoted by a 0-10n row label), zero (denoted by a 0-10z row label), and positive (denoted by a 0-10p row label) values of the specified income_measure.

taxcalc.utils.delete_file(filename)

Remove specified file if it exists.

taxcalc.utils.expected_utility(consumption, probability, crra, cmin)

Calculate and return expected utility of consumption.

Parameters:

• consumption (numpy array) – consumption for each filing unit

• probability (numpy array) – samplying probability of each filing unit

• crra (non-negative float) – constant relative risk aversion parameter of isoelastic utility function

• cmin (positive float) – consumption level below which marginal utility is assumed to be constant

Return type:

expected utility of consumption array

taxcalc.utils.get_sums(dframe)

Compute unweighted sum of items in each column of Pandas DataFrame, dframe.

Return type:

Pandas Series object containing column sums indexed by dframe column names.

taxcalc.utils.isoelastic_utility_function(consumption, crra, cmin)

Calculate and return utility of consumption.

Parameters:

• consumption (float) – consumption for a filing unit

• crra (non-negative float) – constant relative risk aversion parameter

• cmin (positive float) – consumption level below which marginal utility is assumed to be constant

Return type:

utility of consumption

taxcalc.utils.json_to_dict(json_text)

Convert specified JSON text into an ordered Python dictionary.

Parameters:

json_text (string) – JSON text.

Raises:

ValueError: – if json_text contains a JSON syntax error.

Returns:

dictionary – JSON data expressed as an ordered Python dictionary.

Return type:

collections.OrderedDict

taxcalc.utils.mtr_graph_data(vdf, year, mars='ALL', mtr_measure='combined', mtr_variable='e00200p', alt_e00200p_text='', mtr_wrt_full_compen=False, income_measure='expanded_income', pop_quantiles=False, dollar_weighting=False)

Prepare marginal tax rate data needed by xtr_graph_plot utility function.

Parameters:

• vdf (a Pandas DataFrame object containing variables and marginal tax rates) – (See Calculator.mtr_graph method for required elements of vdf.)

• year (integer) – specifies calendar year of the data in vdf

• mars (integer or string) –

  specifies which filing status subgroup to show in the graph

  • ’ALL’: include all filing units in sample

  • 1: include only single filing units

  • 2: include only married-filing-jointly filing units

  • 3: include only married-filing-separately filing units

  • 4: include only head-of-household filing units

• mtr_measure (string) –

  specifies which marginal tax rate to show on graph’s y axis

  • ’itax’: marginal individual income tax rate

  • ’ptax’: marginal payroll tax rate

  • ’combined’: sum of marginal income and payroll tax rates

• mtr_variable (string) – any string in the Calculator.VALID_MTR_VARS set specifies variable to change in order to compute marginal tax rates

• alt_e00200p_text (string) – text to use in place of mtr_variable when mtr_variable is ‘e00200p’; if empty string then use ‘e00200p’

• mtr_wrt_full_compen (boolean) – see documentation of Calculator.mtr() argument wrt_full_compensation (value has an effect only if mtr_variable is ‘e00200p’)

• income_measure (string) –

  specifies which income variable to show on the graph’s x axis

  • ’wages’: wage and salary income (e00200)

  • ’agi’: adjusted gross income, AGI (c00100)

  • ’expanded_income’: sum of AGI, non-taxable interest income, non-taxable social security benefits, and employer share of FICA taxes.

• pop_quantiles (boolean) – specifies whether or not quantiles contain an equal number of people (True) or an equal number of filing units (False)

• dollar_weighting (boolean) – False implies both income_measure percentiles on x axis and mtr values for each percentile on the y axis are computed without using dollar income_measure weights (just sampling weights); True implies both income_measure percentiles on x axis and mtr values for each percentile on the y axis are computed using dollar income_measure weights (in addition to sampling weights). Specifying True produces a graph x axis that shows income_measure (not filing unit) percentiles.

Return type:

dictionary object suitable for passing to xtr_graph_plot utility function

taxcalc.utils.pch_graph_data(vdf, year, pop_quantiles=False)

Prepare percentage change in after-tax expanded income data needed by pch_graph_plot utility function.

Parameters:

• vdf (a Pandas DataFrame object containing variables) – (See Calculator.pch_graph method for required elements of vdf.)

• year (integer) – specifies calendar year of the data in vdf

• pop_quantiles (boolean) – specifies whether or not quantiles contain an equal number of people (True) or an equal number of filing units (False)

Return type:

dictionary object suitable for passing to pch_graph_plot utility function

taxcalc.utils.pch_graph_plot(data, width=850, height=500, xlabel='', ylabel='', title='')

Plot percentage change in after-tax expanded income using data returned from the pch_graph_data function.

Parameters:

• data (dictionary object returned from ?tr_graph_data() utility function) –

• width (integer) – width of plot expressed in pixels

• height (integer) – height of plot expressed in pixels

• xlabel (string) – x-axis label; if ‘’, then use label generated by pch_graph_data

• ylabel (string) – y-axis label; if ‘’, then use label generated by pch_graph_data

• title (string) – graph title; if ‘’, then use title generated by pch_graph_data

Return type:

bokeh.plotting figure object containing a raster graphics plot

Notes

See Notes to xtr_graph_plot function.

taxcalc.utils.read_egg_csv(fname, index_col=None)

Read from egg the file named fname that contains CSV data and return pandas DataFrame containing the data.

taxcalc.utils.read_egg_json(fname)

Read from egg the file named fname that contains JSON data and return dictionary containing the data.

taxcalc.utils.unweighted_sum(dframe, col_name)

Return unweighted sum of Pandas DataFrame col_name items.

taxcalc.utils.weighted_sum(dframe, col_name)

Return weighted sum of Pandas DataFrame col_name items.

taxcalc.utils.write_graph_file(figure, filename, title)

Write HTML file named filename containing figure. The title is the text displayed in the browser tab.

Parameters:

• figure (bokeh.plotting figure object) –

• filename (string) – name of HTML file to which figure is written; should end in .html

• title (string) – text displayed in browser tab when HTML file is displayed in browser

Return type:

Nothing

taxcalc.utils.xtr_graph_plot(data, width=850, height=500, xlabel='', ylabel='', title='', legendloc='bottom_right')

Plot marginal/average tax rate graph using data returned from either the mtr_graph_data function or the atr_graph_data function.

Parameters:

• data (dictionary object returned from ?tr_graph_data() utility function) –

• width (integer) – width of plot expressed in pixels

• height (integer) – height of plot expressed in pixels

• xlabel (string) – x-axis label; if ‘’, then use label generated by ?tr_graph_data

• ylabel (string) – y-axis label; if ‘’, then use label generated by ?tr_graph_data

• title (string) – graph title; if ‘’, then use title generated by ?tr_graph_data

• legendloc (string) – options: ‘top_right’, ‘top_left’, ‘bottom_left’, ‘bottom_right’ specifies location of the legend in the plot

Return type:

bokeh.plotting figure object containing a raster graphics plot

Notes

USAGE EXAMPLE:

gdata = mtr_graph_data(...)
gplot = xtr_graph_plot(gdata)

THEN when working interactively in a Python notebook:

bp.show(gplot)

OR when executing script using Python command-line interpreter:

bio.output_file('graph-name.html', title='?TR by Income Percentile')
bio.show(gplot)  [OR bio.save(gplot) WILL JUST WRITE FILE TO DISK]

WILL VISUALIZE GRAPH IN BROWSER AND WRITE GRAPH TO SPECIFIED HTML FILE

To convert the visualized graph into a PNG-formatted file, click on the “Save” icon on the Toolbar (located in the top-right corner of the visualized graph) and a PNG-formatted file will written to your Download directory.

The ONLY output option the bokeh.plotting figure has is HTML format, which (as described above) can be converted into a PNG-formatted raster graphics file. There is no option to make the bokeh.plotting figure generate a vector graphics file such as an EPS file.