. Author manuscript; available in PMC: 2009 Jun 2.

Published in final edited form as: Health Econ. 2009 Jun;18(6):727–742. doi: 10.1002/hec.1473

Table VI.

OLS log linear regression of antimalarial tablet prices for shops^a

	Model 1			Model 2
	n 154; F<0.0001; R² 0.9024			n 154; F<0.0001; R² 0.9035
Explanatory variables	Coefficient	Standard error	p Value	Coefficient	Standard error	p Value
HHI volume	0.947	0.320	0.005^*
HHI value				1.028	0.299	0.001^*
Amodiaquine	1.698	0.132	<0.001^*	1.690	0.134	<0.001^*
Quinine	3.490	0.151	<0.001^*	3.454	0.152	<0.001^*
SP	1.886	0.117	<0.001^*	1.883	0.117	<0.001^*
Packaged	0.451	0.104	<0.001^*	0.423	0.104	<0.001^*
Other_Africa	0.187	0.116	0.114	0.158	0.114	0.175
Asia	0.071	0.157	0.654	0.064	0.157	0.685
Europe	0.040	0.162	0.804	0.082	0.160	0.610
Innovator	0.588	0.198	0.005^*	0.555	0.193	0.006^*
Branded_generic	0.163	0.121	0.183	0.145	0.117	0.218
Ulanga	0.237	0.148	0.117	0.298	0.186	0.116
Rufiji	0.172	0.098	0.084	0.137	0.097	0.164
General_store	0.327	0.121	0.010^*	0.314	0.122	0.013^*
Rural_area	0.114	0.105	0.284	0.081	0.095	0.401
Constant	2.707	0.161	<0.001^*	2.683	0.158	<0.001^*

Five observations were dropped because of missing data on country of manufacture or tablet size. Source: Outlet Survey Nov Dec 2001.

Each observation is an antimalarial drug. As the HHI was measured at the sub market level, the strata were defined as the sub markets, and tested with an F test of (14, 34).

Coefficient significant at 5% level.