24. Sopranzetti S. Riding free trade agreements and international trade: a network approach. World Econ. (2018) 41:1549-66. doi: 10.1111/twec.12599 In all section 3 calculations, we defined the average length of the path between the two ITN C1 and C2 sub-graphs. This choice was motivated by the distribution of the probabilities of the average trail length for all pairs of countries through a trade agreement (Figure 11). It thus allows to take into account paths of sufficient quality between these sub-graphs, while avoiding the excessive contributions of the loops inside one of them. As formalized in the equation (2), dependency measures allow the definition of IT output, which describes the probability of a unitary property delivered from C1 to the end in C2. Entry IT describes this probability of a successive payment flow.
In Figure 1, we schematically illustrate the pathways that contribute to IT through an exemplary trade network between China (CHN) and Vietnam (VNM). China`s IT production in Vietnam, TIout (CHN, VNM), is for goods routes originating in China and ending in Vietnam (see Figure 1A). On the other hand, China`s IT input to Vietnam, TIin (VNM, CHN), takes into account the trajectories of financial flows (see Figure 1B). The channels are defined in the opposite direction, as cash flows are used in relation to the supply of materials, goods or services on the commercial network. The definition of IT is not symmetrical: the corresponding paths of this exemplary network that contribute to the TIs from Vietnam to China are represented by Figure 1C for TIout (VNM, CHN) and Figure 1D for TIin (CHN, VNM). Note that in the IT definition, we do not take into account the paths that cross a third country. To search for documents relating to regional trade agreements in the WTO`s online database, follow this link to access the WTO document database and insert the codes in the search engine icon. WTO members are allowed to conclude the RTA under certain conditions, defined in three sentences. These rules include the creation and operation of customs unions and free trade zones for trade in goods (Article XXIV of the 1994 General Agreement on Tariffs and Trade), regional or comprehensive agreements for trade in goods between developing countries (empowerment clause) and trade agreements on services (Article V of the General Agreement on Trade in Services). In general, ATRs must essentially cover all trade – unless they are subject to the enabling clause – and make trade between RTA countries freer without increasing trade barriers with the outside world. Regional trade agreements (ATRs) have multiplied over the years and have achieved, including a significant increase in major multilateral agreements being negotiated.
Non-discrimination between trading partners is one of the fundamental principles of the WTO; However, reciprocal preferential agreements between two or more partners are one of the exceptions and are allowed by the WTO subject to a number of provisions. Information on WTO-notified ATRs is available in the RTA database. The World Trade Organization (WTO) Regional Trade Agreement  provides details on negotiated regional trade agreements. It contains information on all agreements that have been notified to the WTO or for which an announcement was made at an early stage between 1948 and today. When a trade agreement is negotiated between exactly two parties, it is called BTA. Otherwise, a trade agreement with more stakeholders is referred to as a multilateral trade agreement. We are also talking about a BTA when a party (or both parties) consists of a regional trading bloc itself. B, for example, when the European Union negotiates an agreement with Mexico.