Conclusion

The present research is devoted to the analysis of the effects of quantitative and dummy variables on the volume of trade between countries, the impact of entering the economic integration agreements on the dynamics of export of countries that form BRICS, the relationship between trade liberalizations under the different types of EIAs and the values of export between BRICS country and its trading partner. In this study we deal with the problem of endogeneity bias of economic integration agreements through panel techniques - we apply the fixed-effects specification to obtain the precise estimates of the effects of EIAs on the export flows. The fixed-effects estimation is one of the most effective ways of eliminating the endogeneity and, thus, our most precise model is fixed-effects model that includes quantitative control variables such as GDP, population, area, dummy variables such as common official language, acceptance to the European Union, GATT/WTO, one variable that represents the absence of integration between countries and four variables for all types of the agreements. Apart from previous studies, we use а large data set with а huge number of country pairs and years and we adjust our model to the varying types of EIAs. The results of our study are as follows.

The overall R-squared for the basic model and the second model are high enough to say that the obtained coefficients are accurate (see the Appendix 1). The first model failed to provide the proper outcomes. Most of the obtained estimates are precise because they are significant at the one and five percent levels of significance (see Таblе 1 and Таblе 3). Thus, the results of the basic model and second model are correct and we can evaluate whether they coincided with the hypotheses that were proposed in the introduction.

On the one l1and, we are аblе to prove that some of our hypotheses are true. We confirmed that the greater the values of GDP or population of the country are, the more it trades. The increase in BRICS country's GDP enlarges the export volume bу 119% and the growth in the GDP of the importing country enhances the import bу 11.5%. The increase in the population of one of the BRICS countries, enlarges the export bу 40%, the same is relevant for the importing country where the growth in the population indexes results in the approximately 41% increase in the volume of import. The membership of the importing country in World Trade Organization (GATT/WTO) and European Union (EU) increases the amount of its import on 73.2% and 92% respectively. This result coincides with the proposed hypothesis that if trading partners are the members of World Trade Organization (GATT/WTO) or the members of European Union (EU) then they trade with BRICS countries more.We found that that the absence of integration between countries lowers the values of export on approximately 52%. It is in line with the hypothesis that the absence of integration between trading countries lowers the volumes of trade.

On the other hand, some of the proposed hypotheses proved to bе wrong. For example, the existence of common official language decreases the export from BRICS country on 87%. Thus, if countries have common official language then they trade less in opposite to our statement in the introduction. That саn bе explained due to the fact that the official languages of BRICS countries are mainly utilized only in these countries and, thus, they trade more with countries which have other languages. The size of the area of the trading countries affects the trade differently. The larger the area of the BRICS country is, the less it exports (31% less), but the greater the size of the importing country is, the more it imports (24% more). So, the outcome doesn't match our hypothesis for BRICS countries and the greater the values of area of the BRICS country are, the less it trades. Although, the hypothesis is true for the trading partner.

Furthermore, we answered our research question and under the establishment of the integration agreements as well as under the deepening of the partnership between BRICS and importing countries the effects on export values are positive. We confirmed that the OWPTAs have larger trade effects than the deeper EIAs (74% more export under OWPTA), and the TWPTAs have greater effects than FTAs and customs unions, but these results do not fully support one of the hypotheses of our research that the deepening of the partnership between BRICS country and the country that it traded within the period of time 1990-2005 results in the increase in the trade volumes. The reason for it is that the OWPTAs have the largest impact on export values and other types of the agreements have а comparatively small or insignificant effect on the export.

There are several ways to continue this study. Firstly, the future researchers can consider the extensive and intensive goods margins of trade instead of estimating only one­ way export flows from BRICS country to its trading partner. Secondly, they can include more specific economic variables such as the price of the goods, the inflation rate, the quantity of goods exported or imported into the gravity equation to observe the effects of these additional variables on the trade between BRICS countries and their trading partners. Also, а longer time period can bе chosen to derive even more accurate results of the estimation for the models under investigation in the future. The specifications of the standard gravity model proposed in this research can have а practical implementation in other economic works.