inequality¶
Implements inequality and segregation measures such as Gini, Lorenz Curve
-
quantecon.inequality.
gini_coefficient
[source]¶ Implements the Gini inequality index
Parameters: - y : array_like(float)
Array of income/wealth for each individual. Ordered or unordered is fine
Returns: - Gini index: float
The gini index describing the inequality of the array of income/wealth
References
-
quantecon.inequality.
lorenz_curve
[source]¶ Calculates the Lorenz Curve, a graphical representation of the distribution of income or wealth.
It returns the cumulative share of people (x-axis) and the cumulative share of income earned.
Parameters: - y : array_like(float or int, ndim=1)
Array of income/wealth for each individual. Unordered or ordered is fine.
Returns: - cum_people : array_like(float, ndim=1)
Cumulative share of people for each person index (i/n)
- cum_income : array_like(float, ndim=1)
Cumulative share of income for each person index
References
[1] https://en.wikipedia.org/wiki/Lorenz_curve Examples
>>> a_val, n = 3, 10_000 >>> y = np.random.pareto(a_val, size=n) >>> f_vals, l_vals = lorenz(y)
-
quantecon.inequality.
rank_size
(data, c=1.0)[source]¶ Generate rank-size data corresponding to distribution data.
Parameters: - data : array_like
the set of observations
- c : int or float
restrict plot to top (c x 100)% of the distribution
Returns: - rank_data : array_like(float, ndim=1)
Location in the population when sorted from smallest to largest
- size_data : array_like(float, ndim=1)
Size data for top (c x 100)% of the observations
Examples
>>> y = np.exp(np.random.randn(1000)) # simulate data >>> rank_data, size_data = rank_size(y, c=0.85)
-
quantecon.inequality.
shorrocks_index
(A)[source]¶ Implements Shorrocks mobility index
Parameters: - A : array_like(float)
Square matrix with transition probabilities (mobility matrix) of dimension m
Returns: - Shorrocks index: float
The Shorrocks mobility index calculated as
\[s(A) = \frac{m - \sum_j a_{jj} }{m - 1} \in (0, 1)\]An index equal to 0 indicates complete immobility.
References
[1] Wealth distribution and social mobility in the US: A quantitative approach (Benhabib, Bisin, Luo, 2017). https://www.econ.nyu.edu/user/bisina/RevisionAugust.pdf