Table 4

Conditional elasticities and socio-demographic characteristics by income groups

	Low-income households		Middle-income households		High-income households		All households
Conditional demand (intensity) elasticity (Deaton model)
Price	−0.424***	(0.049)	−0.339***	(0.067)	−0.258**	(0.142)	−0.359***	(0.044)
Income	0.174**	(0.085)	0.241**	(0.128)	0.276	0.057	0.205***	(0.050)
Variables	Unit value	Budget share	Unit value	Budget share	Unit value	Budget share	Unit value	Budget share
Total expenditure (ln)	0.148***	−0.034***	0.208***	−0.025***	0.237***	−0.021***	0.191***	−0.029***
	(0.024)	(0.003)	(0.049)	(0.006)	(0.025)	(0.003)	(0.016)	(0.002)
Household size (ln)	−0.077***	0.005	−0.119**	−0.004	−0.129***	0.000	−0.098***	0.003*
	(0.026)	(0.004)	(0.049)	(0.006)	(0.022)	(0.002)	(0.016)	(0.002)
Male ratio	−0.077**	0.009**	−0.012	0.018***	−0.033	0.013***	−0.032**	0.014***
	(0.034)	(0.005)	(0.030)	(0.003)	(0.021)	(0.002)	(0.015)	(0.002)
Adult ratio	−0.108***	0.008*	−0.152***	0.004	−0.168***	0.012**	−0.133***	0.009***
	(0.034)	(0.005)	(0.038)	(0.004)	(0.051)	(0.005)	(0.022)	(0.003)
Maximum education: more than secondary complete
No education	−0.144*	0.073***	−0.107	0.002	−0.068	0.013*	−0.097**	0.029***
	(0.079)	(0.011)	(0.082)	(0.009)	(0.069)	(0.007)	(0.044)	(0.005)
Primary complete	−0.066***	0.006*	−0.092***	0.000	−0.110***	−0.001	−0.091***	0.001
	(0.024)	(0.003)	(0.025)	(0.003)	(0.025)	(0.003)	(0.014)	(0.002)
Secondary complete	−0.034*	0.003	−0.025	0.002	−0.073***	0.001	−0.049***	0.001
	(0.019)	(0.003)	(0.016)	(0.002)	(0.016)	(0.002)	(0.010)	(0.002)
HH activity: employed
Unemployed	−0.025	−0.002	−0.076*	0.004	−0.111*	−0.009	−0.046**	0.000
	(0.027)	(0.004)	(0.043)	(0.005)	(0.064)	(0.006)	(0.021)	(0.003)
Pensioners	−0.074***	0.001	−0.061***	−0.007***	−0.113***	−0.007***	−0.085***	−0.005***
	(0.020)	(0.003)	(0.020)	(0.002)	(0.018)	(0.002)	(0.011)	(0.001)
Constant	−0.815***	0.240***	−1.136***	0.198***	−1.217***	0.167***	−1.020***	0.214***
	(0.132)	(0.018)	(0.272)	(0.031)	(0.170)	(0.017)	(0.096)	(0.011)
Number of clusters	169	169	175	175	172	172	518	518
Cluster effect F¹	12.967***	2.321**	12.161***	3.147***	9.906***	3.509***	11.735***	2.938***
Observations	1869	1869	2017	2017	1907	1907	5793	5793
R-squared	0.612	0.348	0.587	0.337	0.592	0.360	0.609	0.340

Source: Own calculation; ***p<0.01, **p<0.05, *p<0.1.
Cluster fixed effects confirm the existence of time and spatial variation (Deaton); SEs for both price and expenditure elasticity are calculated using bootstrap procedure of 1000 replications. Note: Tests showed the absence of statistically significant difference between price elasticities among all income groups: low-income and middle-income groups (χ²(1)=1.39, prob >χ²=0.2379); low-income and high-income groups (χ²(1)=1.48, prob >χ²=0.2239); middle-income and high-income groups (χ²(1)=0.40, prob >χ²=0.5276). Also, test showed the absence of statistically significant difference between income elasticities among all income groups: low-income and middle-income groups (χ²(1)=0.21, prob >χ²=0.6502); low-income and high-income groups (χ²(1)=1.04, prob >χ²=0.3078); middle-income and high-income groups (χ²(1)=0.07, prob >χ²=0.7935).