Assessing regional convergence of the size of middle classes in Euro-Mediterranean countries

Figures & data

Figure 1. Annual changes in lower- and upper- middle-class size. Source: EU-SILC (2004–17) and authors’ own elaboration.

This figure shows the evolution of the lower- and upper-middle class size for each one of the regions in the period 2004–17, where the class size for 2004 is set to 100. Note: class size in 2004 is 100.

Figure 2. Quartile map of lower- and upper-middle-income class size, 2004 and 2017.

This figure shows four quartile map of income class size in 2004 and 2017 as follows: (1) top left, lower-middle income size in 2004; (2) top right, lower-middle income size in 2017; (3) bottom left, upper-middle income size in 2004; and (4) bottom right, upper-middle income size in 2017.

Table 1. Moran’s index test for income classes by population, 2004–17.

Year	Lower-middle class			Upper-middle class
	Index	z-value	p-value	Index	z-value	p-value
2004	0.4667	5.4124	0.0000	0.0067	0.3840	0.3505
2005	0.5742	6.6069	0.0000	−0.0977	−1.0728	0.8583
2006	0.6431	7.3728	0.0000	0.0602	1.1312	0.1290
2007	0.4864	5.6321	0.0000	0.0191	0.5584	0.2883
2008	0.6769	7.7482	0.0000	0.3420	5.0650	0.0000
2009	0.5338	6.1588	0.0000	0.1793	2.7940	0.0026
2010	0.5242	6.0522	0.0000	0.1728	2.7032	0.0034
2011	0.6724	7.6983	0.0000	0.2169	3.3188	0.0005
2012	0.5777	6.6465	0.0000	0.1474	2.3494	0.0094
2013	0.6498	7.4469	0.0000	0.2488	3.7647	0.0001
2014	0.6981	7.9835	0.0000	0.1743	2.7243	0.0032
2015	0.6565	7.5220	0.0000	0.4154	6.0898	0.0000
2016	0.6043	6.9417	0.0000	0.0699	1.2670	0.1026
2017	0.7164	8.1869	0.0000	0.3212	4.7754	0.0000

Note: When the z-value > −1.96 and < 1.96, Moran’s index suggests there is a high likelihood that the spatial distribution of the residuals is the result of a random process. Otherwise, the p-value < 0.05 and the hypothesis of no spatial correlation is rejected at a 5% probability level. The weight matrix used is four nearest neighbours for lower-middle-income class and six nearest neighbours for upper-middle-income class.

Table 2. Conditional convergence model estimation (SDM): decomposition of gross domestic product (GDP) growth rate.

	Lower-middle		Upper-middle
Determinants	Coefficient	t-statistic	Coefficient	t-statistic
Intercept	0.003	0.289	0.045*	1.774
Initial class size	−0.411***	−15.928	−1.071***	−21.725
W*Initial class size	0.413***	12.041	0.863***	7.676
Neighbours’ class size growth rate	0.235***	3.916	0.311***	4.657
GDP variation rate (positive)	−0.189	−1.207	0.192	1.026
GDP variation rate (negative)	−0.274	−1.495	0.051	0.304
W*GDP variation rate (positive)	−0.242	−1.169	0.102	0.394
W*GDP variation rate (negative)	0.819***	3.056	−0.305	−0.960
R^2	0.365		0.504
Adjusted R^2	0.338		0.471
Log-likelihood ratio	1178.75		1087.11
Residuals variance	0.0004		0.0006
Observations	480		480

Note: Statistically significant at *10%, **5% and ***1%.

Table 3. Conditional convergence. Estimation of direct and indirect effects.

	Direct effect	Indirect effect	Total effect
Initial class size (lower-middle)	−0.395*** (−16.195)	0.400*** (10.809)	0.005 (0.153)
GDP variation rate (positive)	−0.196 (−1.247)	−0.368 (−1.630)	−0.564*** (−2.924)
GDP variation rate (negative)	−0.253 (−1.474)	0.972*** (3.191)	0.719*** (3.659)
Initial class size (upper-middle)	−1.047*** (−21.809)	0.754*** (5.185)	−0.293** (−2.138)
GDP variation rate (positive)	0.206 (1.165)	0.215 (0.678)	0.421 (1.475)
GDP variation rate (negative)	0.037 (0.237)	−0.394 (−1.006)	−0.357 (−1.086)

Note: Statistically significant at *10%, **5% and ***1%, t-statistics are shown in parentheses.

DATA AVAILABILITY

This paper used European Union Statistics on Income and Living Conditions (EU-SILC) data, which are public and can be freely accessed by contacting EUROSTAT. However, the authors cannot provide it due to the privacy clause signed in the contract with EUROSTAT.