Food Prices and Overweight Patterns in Italy

41

Table 5: Identification, estimates and residual diagnostics of the VECM and elasticity of substitution by sub-samples

VARIABLES		VAR SPECIFICATION		THEORETICAL RESTRICTIONS		VECM DIAGNOSTIC	ELASTICITY OF SUBSTITUTION
		Lag order	Rank of cointegration	Symmetry	Homogeneity and symmetry	Residuals serial correlation	η21	η12		Net effect ∆(η21 - η12)
Gender	Male	3	2	3.484 (1) [.062]	10.84 (3) [.012]	39.66[.309]	0.533 (.063)	0.354	(.044)	0.178
	Female	3	2	10.723 (1) [.001]	3.517 (3) [.318]	39.280[.325]	0.222 (.021)	0.140	(.013)	0.081
Education	High	2	3				not significant
	Low	3	2	0.237(1) [.625]	9.693 (3) [.021]	38.828[.343]	0.689 (.201)	0.456	(.127)	0.233
Relative poverty	Above	3	2				not significant
threshold	Below	4	2	0.170 (1) [.679]	11.91 (3) [.007]	47.711[.092]	0.591(.189)	0.394	(.124)	0.196
Age	< 35	2	2				not significant
	35 - 49	4	2	0.509 (1) [.475]	12.438 (3) [.006]	76.077[.348]	0.393 (.192)	0.267	(.130)	0.126
	50 - 64	3	2	1.878 (1) [.170]	2.947 (3) [.407]	38.043[.376]	0.543 (.064)	0.359	(.043)	0.184
	> 65	3	2	0.133 (1) [.714]	6.583 (3) [.086]	52.453[.037]	0.321 (.039)	0.201	(.024)	0.119

Note: High education stands for people that achieved a degree, master or PhD. Low education for the others. The criterium used to select the optimal lag order is the sequential modified LR test statistic.
The test of the rank of cointegration of the unrestricted VAR use the Johansen’s procedure. Cointegration test inferences of the AI model applied to each subsample are reported in Appendix. Degree of
freedom and p-values of the LR tests for the theoretical restrictions are reported in round and square brackets, respectively. Diagnostic autocorrelation test and estimations of substitution elasticities are
obtained by imposing symmetry and homogeneity in the VECM. Q-statistics distributed as a χ² is reported with the p-values in square brackets. The degree of freedom are 36 for VAR lag order of 3 and 72
for lag order of 4. In round brackets are reported bootstrap standard errors of the estiamated elasticities.