Zenga's New Index of Economic Inequality, Its Estimation, and an Analysis of Incomes in Italy

Table 3

Confidence intervals for 𝑍_𝐹 in the 2006 Italian income distribution.

	𝑍𝑛 estimator				𝑍𝑛 estimator
	95%		99%		95%		99%
	Lower	Upper	Lower	Upper	Lower	Upper	Lower	Upper
Northwest∶𝑛=1988, 𝑍𝑛=0.5953, 𝑍𝑛=0.5948
Normal	0.5775	0.6144	0.5717	0.6202	0.5771	0.6138	0.5713	0.6196
Student	0.5786	0.6168	0.5737	0.6240	0.5791	0.6172	0.5748	0.6243
Percent	0.5763	0.6132	0.5710	0.6193	0.5758	0.6124	0.5706	0.6185
BCa	0.5789	0.6160	0.5741	0.6234	0.5785	0.6156	0.5738	0.6226
Northeast∶𝑛=1723, 𝑍𝑛=0.6108, 𝑍𝑛=0.6108
Normal	0.5849	0.6393	0.5764	0.6478	0.5849	0.6393	0.5764	0.6479
Student	0.5874	0.6526	0.5796	0.6669	0.5897	0.6538	0.5836	0.6685
Percent	0.5840	0.6379	0.5773	0.6476	0.5839	0.6379	0.5772	0.6475
BCa	0.5894	0.6478	0.5841	0.6616	0.5894	0.6479	0.5842	0.6615
Center∶𝑛=1574, 𝑍𝑛=0.6316, 𝑍𝑛=0.6316
Normal	0.5957	0.6708	0.5839	0.6826	0.5956	0.6708	0.5838	0.6827
Student	0.5991	0.6991	0.5897	0.7284	0.6036	0.7016	0.5977	0.7311
Percent	0.5948	0.6689	0.5864	0.6818	0.5948	0.6688	0.5863	0.6818
BCa	0.6024	0.6850	0.5963	0.7021	0.6024	0.6850	0.5963	0.7020
South∶𝑛=1620, 𝑍𝑛=0.6557, 𝑍𝑛=0.6543
Normal	0.6358	0.6770	0.6293	0.6834	0.6346	0.6756	0.6282	0.6820
Student	0.6371	0.6805	0.6313	0.6902	0.6371	0.6796	0.6320	0.6900
Percent	0.6351	0.6757	0.6286	0.6828	0.6337	0.6742	0.6276	0.6812
BCa	0.6375	0.6793	0.6325	0.6888	0.6363	0.6778	0.6315	0.6873
Islands∶𝑛=861, 𝑍𝑛=0.6109, 𝑍𝑛=0.6095
Normal	0.5918	0.6317	0.5856	0.6380	0.5910	0.6302	0.5848	0.6364
Student	0.5927	0.6339	0.5864	0.6405	0.5928	0.6330	0.5874	0.6401
Percent	0.5897	0.6297	0.5839	0.6360	0.5885	0.6275	0.5831	0.6340
BCa	0.5923	0.6324	0.5868	0.6414	0.5914	0.6307	0.5860	0.6394
Italy (entire population)∶𝑛=7766, 𝑍𝑛=0.6470, 𝑍𝑛=0.6464
Normal	0.6346	0.6596	0.6307	0.6636	0.6341	0.6591	0.6302	0.6630
Student	0.6359	0.6629	0.6327	0.6686	0.6358	0.6627	0.6331	0.6683
Percent	0.6348	0.6597	0.6314	0.6640	0.6343	0.6592	0.6309	0.6635
BCa	0.6363	0.6619	0.6334	0.6676	0.6358	0.6613	0.6330	0.6669