However, in more recent economic literature, a theoretical basis for the gravity model has been derived from the factor proportions model (Deardorff 1998), Ricardo's trade model (Eaton and Kortum 2001 , 2002 or monopolistic competition with differentiated products (Anderson and van Wincoop 2003; Bergstrand et al. 2013).
The distributions of potential influencing factor proportions were compared by the χ test.
No significant differences were found in demographic factors, proportion of interns, and proportion of categorical residents between the groups of subjects viewing the video of the veteran vs. the non-veteran (Table 1).
Several SES factors (proportion of management positions, years of continuous employment, and annual household income) and folate intake were found to be significantly lower in the subjects with depressive symptom (SES factors: p < 0.001; folate intake: P = 0.001).
As to SES factors, proportion of management positions, years of continuous employment, and unadjusted annual household income were found to be significantly lower in the subjects with depressive symptom.
Of the five factors, proportion of primary inocula as sexual propagules and cost of virulence accounted for most variation (measured as deviance) in TF: 12.6% and 10.1%, respectively (Table 1).
The first part of this course covers the factor-proportions theory of international trade.
The first part of this course covers Ricardian, factor-proportions and monopolistic-competition models of international trade.
