Araştırma Makalesi
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Yenilenmiş Akıllı Telefon Pazarının Makine Öğrenmesi ile Analizi

Yıl 2026, Cilt: 40 Sayı: 1, 42 - 59, 01.01.2026
https://doi.org/10.16951/trendbusecon.1607949

Öz

Yenilenmiş akıllı telefon pazarı, ekonomik ve çevresel faydaları nedeniyle son zamanlarda dikkat çekmektedir. Özellikle, artan çevre bilinci ve uygun maliyetli alternatiflerin aranması, yenilenmiş ürünlere olan talebi artırmıştır. Ancak, bu pazarın dinamikleri ve fiyatlandırma uygulamaları, yeni cihaz pazarından farklıdır.
Fiyat oluşumu, cihazın durumu ve modeli gibi ürüne özgü çeşitli faktörlere bağlıdır. Ancak, bu çok faktörlü yapıyı analiz etmek ve doğru fiyat tahminleri yapmak tüketiciler, satıcılar ve yeniden üreticiler için hala zorlu bir görevdir. Bu bağlamda, makine öğrenimi yüksek doğrulukta fiyat tahmini yapılmasına destek olabilir.
Yenilenmiş akıllı telefonlar için özellik tabanlı fiyat tahmin modelleri geliştirmek, fiyat dalgalanmalarını açıklamaya ve kullanım ve yenileme sonrası durumu dikkate alarak cihazın değerini tahmin etmeye yardımcı olur. Bu çalışmada, tahmin doğruluğunu artırmak için hem geleneksel makine öğrenimi hem de derin öğrenme yöntemleri kullanılmıştır. Model performansı MSE, MAE, RMSE ve R² puanı kullanılarak değerlendirilmiştir. XGB Regressor, geleneksel makine öğrenimi algoritmaları arasında 0,9902 R² ile en iyi sonucu elde etmiştir. Derin öğrenme modelleri arasında LSTM de 0,9870 R² ile güçlü bir performans göstermiştir.

Teşekkür

SENATECH BİLGİ TEKNOLOJİLERİ SANAYİ TİCARET A.Ş.'ye gerçek piyasa verilerine ulaşma, sektörel deneyimlerle çalışmanın bulgularını doğrulama ve alan uzmanlarıyla saha araştırmaları gerçekleştirme konusundaki değerli katkıları için içten teşekkürlerimizi sunarız.

Kaynakça

  • Agostini, L., Bigliardi, B., Filippelli, S., & Galati, F. (2021). Seller reputation, distribution and intention to purchase refurbished products. Journal of Cleaner Production, 316, 128296. https://doi.org/10.1016/j.jclepro.2021.128296.
  • Barros, M., & Dimla, E. (2021). From planned obsolescence to the circular economy in the smartphone industry: An evolution of strategies embodied in product features. Proceedings of the Design Society, 1, 1607-1616. https://doi.org/10.1017/pds.2021.422.
  • F. M. Basysyar and G. Dwilestari. (2022). House price prediction using exploratory data analysis and machine learning with feature selection, Acadlore Trans. Mach. Learn., vol. 1, no. 1, pp. 11-21. https://doi.org/10.56578/ataiml010103.
  • Bigliardi, B., Filippelli, S., & Quinto, I. (2022). Environmentally-conscious behaviours in the circular economy. An analysis of consumers' green purchase intentions for refurbished smartphones. Journal of Cleaner Production, 378, 134379. https://doi.org/10.1016/j.jclepro.2022.134379.
  • Charbuty, B., & Abdulazeez, A. (2021). Classification Based on Decision Tree Algorithm for Machine Learning. (2021). Journal of Applied Science and Technology Trends, 2(01), 20-28. https://doi.org/10.38094/jastt20165.
  • Chen, J., & Lin, S. (2004). A neural network approach-decision neural network (DNN) for preference assessment. in IEEE Transactions on Systems, Man, and Cybernetics, Part C (Applications and Reviews), vol. 34, no. 2, pp. 219-225, May 2004. https://doi.org/10.1109/TSMCC.2003.819703.
  • Chicco D, Warrens MJ, Jurman G. (2021). The coefficient of determination R-squared is more informative than SMAPE, MAE, MAPE, MSE and RMSE in regression analysis evaluation. PeerJ Computer Science 7:e623. https://doi.org/10.7717/peerj-cs.623.
  • Dhapte, A. (2024, October). Global refurbished smartphone market overview. Market Research Future. Retrieved from https://www.marketresearchfuture.com/reports/refurbished-smartphone-market-11690.
  • Gülmez, B., & Kulluk, S. (2023). Türkiye’de ikinci el araçların büyük veri ve makine öğrenme teknikleriyle analizi ve fiyat tahmini. Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi, 38(4), 2279-2290. https://doi.org/10.17341/gazimmfd.980840.
  • Halim, S., San, G. S., & Oentoro, J. (2022). Identifying factors that influence customers’ interest in buying refurbished smartphones: An Indonesian context. Petra Christian University, https://so01.tci- thaijo.org/index.php/APST/article/view/258256.
  • Harms, R., & Linton, J. D. (2016). Willingness to pay for eco‐certified refurbished products: The effects of environmental attitudes and knowledge. Journal of industrial ecology, 20(4), 893-904. https://doi.org/10.1111/jiec.12301.
  • Hazelwood, D. A., & Pecht, M. G. (2021). Life extension of electronic products: a case study of smartphones. Ieee Access, 9, 144726-144739. https://doi.org/10.1109/ACCESS.2021.3121733.
  • Hodson, T. O. (2022). Root mean square error (RMSE) or mean absolute error (MAE): When to use them or not. Geoscientific Model Development Discussions, 2022, 1-10. https://doi.org/10.5194/gmd-15-5481-2022.
  • Hossain, M. S., Al-Hamadani, S. M., & Rahman, M. T. (2015). E-waste: a challenge for sustainable development. Journal of Health Pollution, 5(9), 3-11. https://doi.org/10.5696/2156-9614-5-9.3.
  • Intelligence, M. (2023). Used and refurbished smartphone market size. Mordor Intelligence. Retrieved from https://www.mordorintelligence.com/industry-reports/used-and-refurbished-smartphone-market.
  • Jose, J., Raj, V., Seaban, S. V., & Jose, D. V. (2023). Machine Learning Algorithms for Prediction of Mobile Phone Prices. Paper presented at the International Conference On Innovative Computing And Communication. https://doi.org/10.1007/978-981-99-3010-4_7.
  • Long, W., Lu, Z., & Cui, L. (2019). Deep learning-based feature engineering for stock price movement prediction. Knowledge-Based Systems, 164, 163-173. https://doi.org/10.1016/j.knosys.2018.10.034.
  • Mhatre, P., & Srivatsa, H. S. (2019). Modelling the purchase intention of millennial and Generation X consumers, towards refurbished mobile phones in India. International Journal of Green Economics, 13(3-4), 257-275. https://doi.org/10.1504/IJGE.2019.104512.
  • Montgomery, D. C., Peck, E. A., & Vining, G. G. (2021). Introduction to linear regression analysis: John Wiley & Sons.
  • Mugge, R., Jockin, B., & Bocken, N. (2017). How to sell refurbished smartphones? An investigation of different customer groups and appropriate incentives. Journal of Cleaner Production, 147, 284-296. https://doi.org/10.1016/j.jclepro.2017.01.111.
  • Muljani, N., & Koesworo, Y. (2019). The impact of brand image, product quality and price on purchase intention of smartphone. International Journal of Research Culture Society, 3(1), 99-103. https://repository.ukwms.ac.id/id/eprint/18107.
  • Nousi, P., Tsantekidis, A., Passalis, N., Ntakaris, A., Kanniainen, J., Tefas, A., & Iosifidis, A. (2019). Machine learning for forecasting mid-price movements using limit order book data. IEEE Access, 7, 64722–64736. https://doi.org/10.1109/ACCESS.2019.2916793.
  • Pachange, S. (2023, September 4). Refurbished smartphone market growth, size, share, demand, trends, and forecasts to 2032. Custom Market Insights. Retrieved from https://www.custommarketinsights.com/report/refurbished-smartphone-market/.
  • Patel, J., Shah, S., Thakkar, P., & Kotecha, K. (2015). Predicting stock and stock price index movement using trend deterministic data preparation and machine learning techniques. Expert systems with applications, 42(1), 259-268. https://doi.org/10.1016/j.eswa.2014.07.040.
  • Plan, C. E. A. (2020). For a cleaner and more competitive Europe. European Commission : Brussels, Belgium, 28.
  • Plevris, V., Solorzano, G., Bakas, N. P., & Ben Seghier, M. (2022). Investigation of performance metrics in regression analysis and machine learning-based prediction models. Paper presented at the 8th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS Congress 2022). https://doi.org/10.23967/eccomas.2022.155.
  • Polat, M., & Akan, Y. (2020). Akıllı Telefon Piyasasında Firmalar Arasındaki Rekabetin Stratejik Olarak İncelenmesi: Oyun Teorisi Kapsamında Uygulamalı Bir Çalışma. Iğdır Üniversitesi Sosyal Bilimler Dergisi(24), 677-700.
  • Rana, D. S., Dhondiyal, S. A., Singh, S., Kukreti, S., & Dhyani, A. (2024). Predicting Mobile Prices with Machine Learning Techniques. Paper presented at the 2024 International Conference on Computational Intelligence and Computing Applications (ICCICA). https://doi.org/10.1109/ICCICA60014.2024.10585222.
  • Richter, J. L., Svensson-Hoglund, S., Frolov, T., Dalhammar, C., Thidell, A., & Russell, J. (2021). Reaping What WEEE Sow: The potential for harvesting spare parts for repair and refurbishment. Paper presented at the 4th Conference on Product Lifetimes and the Environment (PLATE), Limerick. https://doi.org/10.31880/10344/10240.
  • Rientjes, A., & Denis, S. Strategic marketing as a driver of sustainable consumption: Use-case in the smartphone industry (Master’s thesis, Université catholique de Louvain). Louvain School of Management. http://hdl.handle.net/2078.1/thesis:45599.
  • Russell, J. D., & Nasr, N. Z. (2023). Value-retained vs. impacts avoided: the differentiated contributions of remanufacturing, refurbishment, repair, and reuse within a circular economy. Journal of Remanufacturing, 13(1), 25-51. https://doi.org/10.1007/s13243-022-00119-4.
  • Sherstinsky, A. (2020). Fundamentals of recurrent neural network (RNN) and long short-term memory (LSTM) network. Physica D: Nonlinear Phenomena, 404, 132306. https://doi.org/10.1016/j.physd.2019.132306.
  • Srikanth, B., Sharma, S., Chaubey, V. P., & Kumar, A. (2023). Forecasting the Prices using Machine Learning Techniques: Special Reference to used Mobile Phones. Paper presented at the 2023 Second International Conference on Augmented Intelligence and Sustainable Systems (ICAISS). https://doi.org/10.1109/ICAISS58487.2023.10250685.
  • Tatachar, A. V. (2021). Comparative assessment of regression models based on model evaluation metrics. International Journal of Innovative Technology Exploring Engineering, 8(9), 853-860.
  • Van Weelden, E., Mugge, R., & Bakker, C. (2016). Paving the way towards circular consumption: exploring consumer acceptance of refurbished mobile phones in the Dutch market. Journal of Cleaner Production, 113, 743-754. https://doi.org/10.1016/j.jclepro.2015.11.065.
  • Vorasayan, J., & Ryan, S. M. (2006). Optimal price and quantity of refurbished products. Production Operations Management, 15(3), 369-383. https://doi.org/10.1111/j.1937-5956.2006.tb00251.x.
  • Weng, B. (2017). Application of machine learning techniques for stock market prediction (Order No. 30265729). Available from ProQuest Dissertations & Theses Global. (2779138486). Retrieved from https://www.proquest.com/dissertations-theses/application-machine-learning-techniques-stock/docview/2779138486/se-2.
  • Wiche, P., Pequeño, F., & Granato, D. (2022). Life cycle analysis of a refurbished smartphone in Chile. Paper presented at the E3S Web of Conferences. https://doi.org/10.1051/e3sconf/202234901011.
  • Zhang, X., Hu, Y., Xie, K., Wang, S., Ngai, E., & Liu, M. (2014). A causal feature selection algorithm for stock prediction modeling. Neurocomputing, 142, 48-59. https://doi.org/10.1016/j.neucom.2014.01.057.

Analysing the Refurbished Smart Phone Market with Machine Learning

Yıl 2026, Cilt: 40 Sayı: 1, 42 - 59, 01.01.2026
https://doi.org/10.16951/trendbusecon.1607949

Öz

The refurbished smartphone market has recently attracted attention because of its economic and environmental benefits. In particular, rising environmental awareness and the search for cost-effective alternatives have increased demand for refurbished products. However, the dynamics of this market and its pricing practices differ from those of the new-device market.
Price formation depends on several product-specific factors, including device condition and model. Yet, analysing this multi-factor structure and producing accurate price estimates remains challenging for consumers, sellers, and remanufacturers. In this context, machine learning can support high-accuracy price prediction.
Developing feature-based price prediction models for refurbished smartphones helps to explain price fluctuations and to estimate a device’s value by considering usage and post-refurbishment condition. In this study, both traditional machine learning and deep learning methods are used to improve prediction accuracy. Model performance is evaluated using MSE, MAE, RMSE, and the R² score. The XGB Regressor achieved the best result among the traditional machine learning algorithms, with an R² of 0.9902. Among the deep learning models, LSTM also performed strongly, reaching an R² of 0.9870.

Teşekkür

We thank SENATECH Information Technology Industry Trade Inc. for giving us real market data, using its industry knowledge to check the study's results, and doing field research with professionals in this field.

Kaynakça

  • Agostini, L., Bigliardi, B., Filippelli, S., & Galati, F. (2021). Seller reputation, distribution and intention to purchase refurbished products. Journal of Cleaner Production, 316, 128296. https://doi.org/10.1016/j.jclepro.2021.128296.
  • Barros, M., & Dimla, E. (2021). From planned obsolescence to the circular economy in the smartphone industry: An evolution of strategies embodied in product features. Proceedings of the Design Society, 1, 1607-1616. https://doi.org/10.1017/pds.2021.422.
  • F. M. Basysyar and G. Dwilestari. (2022). House price prediction using exploratory data analysis and machine learning with feature selection, Acadlore Trans. Mach. Learn., vol. 1, no. 1, pp. 11-21. https://doi.org/10.56578/ataiml010103.
  • Bigliardi, B., Filippelli, S., & Quinto, I. (2022). Environmentally-conscious behaviours in the circular economy. An analysis of consumers' green purchase intentions for refurbished smartphones. Journal of Cleaner Production, 378, 134379. https://doi.org/10.1016/j.jclepro.2022.134379.
  • Charbuty, B., & Abdulazeez, A. (2021). Classification Based on Decision Tree Algorithm for Machine Learning. (2021). Journal of Applied Science and Technology Trends, 2(01), 20-28. https://doi.org/10.38094/jastt20165.
  • Chen, J., & Lin, S. (2004). A neural network approach-decision neural network (DNN) for preference assessment. in IEEE Transactions on Systems, Man, and Cybernetics, Part C (Applications and Reviews), vol. 34, no. 2, pp. 219-225, May 2004. https://doi.org/10.1109/TSMCC.2003.819703.
  • Chicco D, Warrens MJ, Jurman G. (2021). The coefficient of determination R-squared is more informative than SMAPE, MAE, MAPE, MSE and RMSE in regression analysis evaluation. PeerJ Computer Science 7:e623. https://doi.org/10.7717/peerj-cs.623.
  • Dhapte, A. (2024, October). Global refurbished smartphone market overview. Market Research Future. Retrieved from https://www.marketresearchfuture.com/reports/refurbished-smartphone-market-11690.
  • Gülmez, B., & Kulluk, S. (2023). Türkiye’de ikinci el araçların büyük veri ve makine öğrenme teknikleriyle analizi ve fiyat tahmini. Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi, 38(4), 2279-2290. https://doi.org/10.17341/gazimmfd.980840.
  • Halim, S., San, G. S., & Oentoro, J. (2022). Identifying factors that influence customers’ interest in buying refurbished smartphones: An Indonesian context. Petra Christian University, https://so01.tci- thaijo.org/index.php/APST/article/view/258256.
  • Harms, R., & Linton, J. D. (2016). Willingness to pay for eco‐certified refurbished products: The effects of environmental attitudes and knowledge. Journal of industrial ecology, 20(4), 893-904. https://doi.org/10.1111/jiec.12301.
  • Hazelwood, D. A., & Pecht, M. G. (2021). Life extension of electronic products: a case study of smartphones. Ieee Access, 9, 144726-144739. https://doi.org/10.1109/ACCESS.2021.3121733.
  • Hodson, T. O. (2022). Root mean square error (RMSE) or mean absolute error (MAE): When to use them or not. Geoscientific Model Development Discussions, 2022, 1-10. https://doi.org/10.5194/gmd-15-5481-2022.
  • Hossain, M. S., Al-Hamadani, S. M., & Rahman, M. T. (2015). E-waste: a challenge for sustainable development. Journal of Health Pollution, 5(9), 3-11. https://doi.org/10.5696/2156-9614-5-9.3.
  • Intelligence, M. (2023). Used and refurbished smartphone market size. Mordor Intelligence. Retrieved from https://www.mordorintelligence.com/industry-reports/used-and-refurbished-smartphone-market.
  • Jose, J., Raj, V., Seaban, S. V., & Jose, D. V. (2023). Machine Learning Algorithms for Prediction of Mobile Phone Prices. Paper presented at the International Conference On Innovative Computing And Communication. https://doi.org/10.1007/978-981-99-3010-4_7.
  • Long, W., Lu, Z., & Cui, L. (2019). Deep learning-based feature engineering for stock price movement prediction. Knowledge-Based Systems, 164, 163-173. https://doi.org/10.1016/j.knosys.2018.10.034.
  • Mhatre, P., & Srivatsa, H. S. (2019). Modelling the purchase intention of millennial and Generation X consumers, towards refurbished mobile phones in India. International Journal of Green Economics, 13(3-4), 257-275. https://doi.org/10.1504/IJGE.2019.104512.
  • Montgomery, D. C., Peck, E. A., & Vining, G. G. (2021). Introduction to linear regression analysis: John Wiley & Sons.
  • Mugge, R., Jockin, B., & Bocken, N. (2017). How to sell refurbished smartphones? An investigation of different customer groups and appropriate incentives. Journal of Cleaner Production, 147, 284-296. https://doi.org/10.1016/j.jclepro.2017.01.111.
  • Muljani, N., & Koesworo, Y. (2019). The impact of brand image, product quality and price on purchase intention of smartphone. International Journal of Research Culture Society, 3(1), 99-103. https://repository.ukwms.ac.id/id/eprint/18107.
  • Nousi, P., Tsantekidis, A., Passalis, N., Ntakaris, A., Kanniainen, J., Tefas, A., & Iosifidis, A. (2019). Machine learning for forecasting mid-price movements using limit order book data. IEEE Access, 7, 64722–64736. https://doi.org/10.1109/ACCESS.2019.2916793.
  • Pachange, S. (2023, September 4). Refurbished smartphone market growth, size, share, demand, trends, and forecasts to 2032. Custom Market Insights. Retrieved from https://www.custommarketinsights.com/report/refurbished-smartphone-market/.
  • Patel, J., Shah, S., Thakkar, P., & Kotecha, K. (2015). Predicting stock and stock price index movement using trend deterministic data preparation and machine learning techniques. Expert systems with applications, 42(1), 259-268. https://doi.org/10.1016/j.eswa.2014.07.040.
  • Plan, C. E. A. (2020). For a cleaner and more competitive Europe. European Commission : Brussels, Belgium, 28.
  • Plevris, V., Solorzano, G., Bakas, N. P., & Ben Seghier, M. (2022). Investigation of performance metrics in regression analysis and machine learning-based prediction models. Paper presented at the 8th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS Congress 2022). https://doi.org/10.23967/eccomas.2022.155.
  • Polat, M., & Akan, Y. (2020). Akıllı Telefon Piyasasında Firmalar Arasındaki Rekabetin Stratejik Olarak İncelenmesi: Oyun Teorisi Kapsamında Uygulamalı Bir Çalışma. Iğdır Üniversitesi Sosyal Bilimler Dergisi(24), 677-700.
  • Rana, D. S., Dhondiyal, S. A., Singh, S., Kukreti, S., & Dhyani, A. (2024). Predicting Mobile Prices with Machine Learning Techniques. Paper presented at the 2024 International Conference on Computational Intelligence and Computing Applications (ICCICA). https://doi.org/10.1109/ICCICA60014.2024.10585222.
  • Richter, J. L., Svensson-Hoglund, S., Frolov, T., Dalhammar, C., Thidell, A., & Russell, J. (2021). Reaping What WEEE Sow: The potential for harvesting spare parts for repair and refurbishment. Paper presented at the 4th Conference on Product Lifetimes and the Environment (PLATE), Limerick. https://doi.org/10.31880/10344/10240.
  • Rientjes, A., & Denis, S. Strategic marketing as a driver of sustainable consumption: Use-case in the smartphone industry (Master’s thesis, Université catholique de Louvain). Louvain School of Management. http://hdl.handle.net/2078.1/thesis:45599.
  • Russell, J. D., & Nasr, N. Z. (2023). Value-retained vs. impacts avoided: the differentiated contributions of remanufacturing, refurbishment, repair, and reuse within a circular economy. Journal of Remanufacturing, 13(1), 25-51. https://doi.org/10.1007/s13243-022-00119-4.
  • Sherstinsky, A. (2020). Fundamentals of recurrent neural network (RNN) and long short-term memory (LSTM) network. Physica D: Nonlinear Phenomena, 404, 132306. https://doi.org/10.1016/j.physd.2019.132306.
  • Srikanth, B., Sharma, S., Chaubey, V. P., & Kumar, A. (2023). Forecasting the Prices using Machine Learning Techniques: Special Reference to used Mobile Phones. Paper presented at the 2023 Second International Conference on Augmented Intelligence and Sustainable Systems (ICAISS). https://doi.org/10.1109/ICAISS58487.2023.10250685.
  • Tatachar, A. V. (2021). Comparative assessment of regression models based on model evaluation metrics. International Journal of Innovative Technology Exploring Engineering, 8(9), 853-860.
  • Van Weelden, E., Mugge, R., & Bakker, C. (2016). Paving the way towards circular consumption: exploring consumer acceptance of refurbished mobile phones in the Dutch market. Journal of Cleaner Production, 113, 743-754. https://doi.org/10.1016/j.jclepro.2015.11.065.
  • Vorasayan, J., & Ryan, S. M. (2006). Optimal price and quantity of refurbished products. Production Operations Management, 15(3), 369-383. https://doi.org/10.1111/j.1937-5956.2006.tb00251.x.
  • Weng, B. (2017). Application of machine learning techniques for stock market prediction (Order No. 30265729). Available from ProQuest Dissertations & Theses Global. (2779138486). Retrieved from https://www.proquest.com/dissertations-theses/application-machine-learning-techniques-stock/docview/2779138486/se-2.
  • Wiche, P., Pequeño, F., & Granato, D. (2022). Life cycle analysis of a refurbished smartphone in Chile. Paper presented at the E3S Web of Conferences. https://doi.org/10.1051/e3sconf/202234901011.
  • Zhang, X., Hu, Y., Xie, K., Wang, S., Ngai, E., & Liu, M. (2014). A causal feature selection algorithm for stock prediction modeling. Neurocomputing, 142, 48-59. https://doi.org/10.1016/j.neucom.2014.01.057.
Toplam 39 adet kaynakça vardır.

Ayrıntılar

Birincil Dil İngilizce
Konular Büyük Veri, Modelleme ve Simülasyon, Planlama ve Karar Verme, Yapay Zeka (Diğer)
Bölüm Araştırma Makalesi
Yazarlar

Berrin Beyza Özen 0009-0005-3646-5875

Muhammed Fatih Alaeddinoğlu

Tolga Aydın 0000-0002-8971-3255

Gönderilme Tarihi 30 Aralık 2024
Kabul Tarihi 18 Temmuz 2025
Yayımlanma Tarihi 1 Ocak 2026
Yayımlandığı Sayı Yıl 2026 Cilt: 40 Sayı: 1

Kaynak Göster

APA Özen, B. B., Alaeddinoğlu, M. F., & Aydın, T. (2026). Analysing the Refurbished Smart Phone Market with Machine Learning. Trends in Business and Economics, 40(1), 42-59. https://doi.org/10.16951/trendbusecon.1607949

Content of this journal is licensed under a Creative Commons Attribution 4.0 International License

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