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README.md

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 # PyTradeShifts
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 [![License](https://img.shields.io/badge/License-Apache_2.0-blue.svg)](https://opensource.org/licenses/Apache-2.0) ![Testing](https://github.com/allfed/pytradeshifts/actions/workflows/testing.yml/badge.svg)
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-PyTradeShifts is using a network model to simulate how trade communities might shift due to changes in yield. This is based on the model presented in [Hedlung et al. (2022)](https://iopscience.iop.org/article/10.1088/1748-9326/aca68b). To make it possible to directly use yield reductions to change the trade flows, re-exports have to be accounted for. This is done using the re-export algorithm from [Croft et al. (2018)](https://www.sciencedirect.com/science/article/pii/S0959652618326180), as implemented in Hedlung et al. (2022). 
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+## What this is and what it can be used for
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+PyTradeShifts is using a network model to simulate how trade communities might shift due to changes in yield. This is based on the model presented in [Hedlung et al. (2022)](https://iopscience.iop.org/article/10.1088/1748-9326/aca68b). To make it possible to directly use yield reductions to change the trade flows, we have to account for re-exports. This is done using the re-export algorithm from [Croft et al. (2018)](https://www.sciencedirect.com/science/article/pii/S0959652618326180), as implemented in Hedlung et al. (2022), which allows countries only to export as much as they actually produce. 
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+This allows us to change the trade flows, by changing the yields. Therefore, you can take any yield modelling results you have for different crops, feed them into this model and see how the trade flows change due to the changed yields. All this can be done via a single interface, which is explained below and in the [Jupyter notebooks of this repository](https://github.com/allfed/pytradeshifts/tree/main/scripts). 
 
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 ## Installation
 To install the pytradeshifts Model package, we recommend setting up a virtual environment. This will ensure that the package and its dependencies are isolated from other projects on your machine, which can prevent conflicts and make it easier to manage your dependencies. Here are the steps to follow: