Document Type : Research Paper

Authors

1 PhD Student in Financial Economics, Faculty of Economics and Management, Tabriz University, Tabriz, Iran

2 W.E. Nelson Professor of Financial Economics, University of Portland, Portland, the USA

3 Professor of Financial Economics, Faculty of Economics and Management, Tabriz University, Tabriz, Iran

Abstract

The present research aimed to investigate the relationship between Iran’s stock price index and nine macroeconomic variables during 1996–2019. Three methods were employed to reduce uncertainty, namely three Bayesian averaging methods (BMA, BMS, BAS), weighted average least squares (WALS), and Vselect. The experimental results of the Bayesian methods and WALS showed that the exchange rate and the consumer price index are the most important variables among the nine macroeconomic variables considered in the model. Moreover, the results revealed that the exchange rate has a minor impact on the stock price index, while the stock price index exerts a substantial effect on the exchange rate. The findings of Vselect validated the conclusion that these two variables are the primary drivers of stock price estimation and are present in nearly all predictive models
Introduction
The harmonization of financial markets with the macroeconomic sector is crucial for stabilizing the economy and achieving the adopted policies. In recent years, several significant studies have been conducted on financial markets, particularly the stock market, highlighting their pivotal role in allocating capital resources efficiently in advanced economies. Empirical evidence supports the view that financial markets have evolved in tandem with all sectors of the economy. Therefore, it can be argued that financial markets constitute one of the most vital components of any country’s economy. Throughout history, major economic crises have resulted from the collapse of financial markets, which underscores their critical significance. The financial market comprises several components, with the stock market being a crucial part. Economists view it as a barometer of a country’s economic health due to its ability to reflect macroeconomic asset prices more accurately than other markets. The uncertainty surrounding stock prices in stock markets is a significant aspect of the entire economy, capable of generating and disrupting unsustainable growth. For investors, the risk of participating in an investment is a crucial consideration. To comprehend total risk, it is beneficial to examine two aspects: systematic and non-systematic risk.
The present study aimed to examine the impact of economic factors on stock market prices in Iran with the high degree of risk involved. There is a consensus among economists that asset prices are responsive to economic news, and that stock prices and economic factors are strongly interconnected. Thus, this research investigated the potential impact of macroeconomic factors on the Iranian stock price index from 1996 to 2019 using Bayesian averaging methods, followed by an analysis of the effect size of each variable through the weighted average least square method (WALS).
Materials and Methods
Researchers often draw conclusions based on the assumptions of their selected model, assuming that it can accurately predict real-world situations. However, this approach may overlook true uncertainty, leading to non-conservative conclusions. Statistical models comprise two parts: variables and assumptions, and the model selected based on these assumptions to estimate the variables. Uncertainty exists at both levels. For instance, a researcher estimating the impact of influential factors on an independent variable may choose a model based on their assumptions and report their estimates. But is this the best answer? Another researcher with different assumptions may opt for a different model with lower variance and error. In other words, numerous models may fit the sample data equally well but with different coefficient estimates and standard errors. Bayesian model averaging (BMA) is a robust method that aims to remove uncertainty. It assesses the robustness of results to alternative specifications by computing posterior distributions for coefficients and models. This study employed three models of BMA, BMS, and BAS, using various averaging methods to verify the reliability of the results. Moreover, two non-Bayesian methods, namely WALS and Vselect, were used to select the best variables for predicting the optimal models.
Conclusion
This study tried to investigate the relationship between Iran’s stock market index and nine macroeconomic variables during 1996–2019 by using the models that identify and limit uncertainty. The models selected include three Bayesian averaging models as well as WALS and Vselect which were used to verify the results obtained. The results indicated that only two variables, the exchange rate and consumer price index, are statistically significant when assuming a uniform distribution of the prior distribution function, which is the assumption of the BMS method. The remaining variables are not statistically significant. Furthermore, the estimates derived from the BMA and BAS models were quite similar, with the exception of less important variables. However, the similarity decreased in the BAS method. Moreover, WALS and Vselect confirmed the results obtained from all the three methods.

Keywords

Main Subjects

Abu Nouri, E. & Ziauddin, H. (2019). Yield and volatility between world oil price and stock market index of OPEC member countries. Economic Modeling Quarterly, 14(1), 1-24. [In Persian]
Akbar, M., Khan, S. A., & Khan, F. (2012). The relationship of stock prices and macroeconomic variables revisited: Evidence from Karachi stock exchange. African Journal of Business Management, 6(4), 1315-1322.
Al-Sharkas, A. (2004). the dynamic relationship between macroeconomic factors and the Jordanian stock market. International Journal of Applied Econometrics and Quantitative Studies, 1, 1.
Asgharzadeh, M., Salimi, M. J. & Peymani Forushani, M. (2018). The relationship between the company's fundamental variables, historical prices and macroeconomic variables with stock price movements. Quarterly Journal of Financial Engineering and Securities Management (Portfolio Management), 10(39), 219-233. [In Persian]
Bhunia, A., & Mukhuti, S. (2013). The impact of domestic gold price on stock price indices-An empirical study of Indian stock exchanges. Universal Journal of Marketing and Business Research, 2(2), 35-43.
Bin Amin, M. F., & Rehman, M. Z. (2022). Asymmetric Linkages of Oil Prices, Money Supply, and TASI on Sectoral Stock Prices in Saudi Arabia: A Non-Linear ARDL Approach. SAGE Open, 12(1), 21582440211071110.
Celebi, K., & Hönig, M. (2019). The impact of macroeconomic factors on the German stock market: Evidence for the crisis, pre-and post-crisis periods. International Journal of Financial Studies, 7(2), 18.
Chang, B. H., Meo, M. S., Syed, Q. R., & Abro, Z. (2019). Dynamic analysis of the relationship between stock prices and macroeconomic variables: An empirical study of Pakistan stock exchange. South Asian Journal of Business Studies, 8(3), 229-245.
Chaudhuri, K., & Smiles, S. (2004). Stock market and aggregate economic activity: evidence from Australia. Applied Financial Economics, 14(2), 121-129.
Chen, N. F. (1991). Financial investment opportunities and the macroeconomy. The Journal of Finance, 46(2), 529-554.
Chen, N. F., Roll, R., & Ross, S. A. (1986). Economic forces and the stock market. Journal of business, 383-403.
Danilov, D., & Magnus, J. R. (2004). On the harm that ignoring pretesting can cause. Journal of Econometrics, 122(1), 27-46.
Davidson, I., & Fan, W. (2006, September). When efficient model averaging out-performs boosting and bagging. In European Conference on Principles of Data Mining and Knowledge Discovery (pp. 478-486). Berlin, Heidelberg: Springer Berlin Heidelberg.
De Luca, G., & Magnus, J. R. (2011). Bayesian model averaging and weighted-average least squares: Equivariance, stability, and numerical issues. The Stata Journal, 11(4), 518-544.
Elangkumaran, P., & Navaratnaseel, J. (2021). Macroeconomic variables and stock prices: A study of Colombo Stock Exchange (CSE) in Sri Lanka. Available at SSRN 3886450.
Eslamloian, K. & Zare, H. (2006). Investigating the impact of macro variables and alternative assets on stock prices in Iran: an autocorrelated model with distributive breaks. Iranian Journal of Economic Research, 8(29), 17-46. [In Persian]
Fama, E. F., & Schwert, G. W. (1977). Asset returns and inflation. Journal of financial economics, 5(2), 115-146.
Fernandez, C., Ley, E., & Steel, M. F. (2001). Model uncertainty in cross‐country growth regressions. Journal of applied Econometrics, 16(5), 563-576.
Filis, G., Degiannakis, S., & Floros, C. (2011). Dynamic correlation between stock market and oil prices: The case of oil-importing and oil-exporting countries. International review of financial analysis, 20(3), 152-164.
Gan, C., Lee, M., Yong, H. H. A., & Zhang, J. (2006). Macroeconomic variables and stock market interactions: New Zealand evidence. Investment management and financial innovations, (3, Iss. 4), 89-101.
Geske, R., & Roll, R. (1983). The fiscal and monetary linkage between stock returns and inflation. The journal of Finance, 38(1), 1-33.
Hatem Rad, S., Haqiqat, J., Asgharpour, H. & Aderangi, B. (1401). Evaluating macro factors affecting stock price index: Bayesian averaging approach. Financial and Economic Policy Quarterly, 10 (37), 73-111. [In Persian]
Hashmi, S. M., Chang, B. H., & Bhutto, N. A. (2021). Asymmetric effect of oil prices on stock market prices: New evidence from oil-exporting and oil-importing countries. Resources Policy, 70, 101946.
Hoeting, J. A., Madigan, D., Raftery, A. E., & Volinsky, C. T. (1999). Bayesian model averaging: a tutorial (with comments by M. Clyde, David Draper and EI George, and a rejoinder by the authors. Statistical science, 14(4), 382-417.
Hsing, Y. (2011). Impacts of macroeconomic variables on the US stock market index and policy implications. Economics Bulletin, 31(1), 883-892.
Humpe, A., & Macmillan, P. (2009). Can macroeconomic variables explain long-term stock market movements? A comparison of the US and Japan. Applied financial economics19(2), 111-119.
Ibrahim, M. H., & Yusoff, S. W. (2001). Macroeconomic variables, exchange rate and stock price: A Malaysian perspective. International Journal of Economics, Management and Accounting, 9(2).
Ibrahim, M. H., & Aziz, H. (2003). Macroeconomic variables and the Malaysian equity market: A view through rolling subsamples. Journal of economic studies, 30(1), 6-27.
Jareño, F., & Negrut, L. (2016). US stock market and macroeconomic factors. Journal of Applied Business Research (JABR), 32(1), 325-340.
Jeffreys, H. (1998). The theory of probability. OuP Oxford.
Kalyanaraman, L., & Tuwajri, B. (2014). Macroeconomic forces and stock prices: Some empirical evidence from Saudi Arabia. International journal of financial research, 5(1).
Kaplan, D., & Lee, C. (2018). Optimizing prediction using Bayesian model averaging: Examples using large-scale educational assessments. Evaluation review, 42(4), 423-457.
Kass, R. E., & Raftery, A. E. (1995). Bayes factors. Journal of the American statistical association, 90(430), 773-795.
Kaur, J., & Chaudhary, R. (2022). Relationship between macroeconomic variables and sustainable stock market index: an empirical analysis. Journal of Sustainable Finance & Investment, 1-18.
Khan, M. K., Teng, J. Z., Khan, M. I., & Khan, M. F. (2023). Stock market reaction to macroeconomic variables: An assessment with dynamic autoregressive distributed lag simulations. International Journal of Finance & Economics, 28(3), 2436-2448.
Khan, M. N., & Zaman, S. (2012). Impact of macroeconomic variables on stock prices: Empirical evidence from Karachi Stock Exchange, Pakistan. In Business, Economics, Financial Sciences, and Management (pp. 227-233). Springer Berlin Heidelberg.
Kilian, L., & Park, C. (2009). The impact of oil price shocks on the US stock market. International economic review, 50(4), 1267-1287.
Leamer, E. E. (1978). Specification searches: Ad hoc inference with nonexperimental data. (No Title).
Mawardi, I., Widiastuti, T., & Sukmaningrum, P. S. (2019). The impact of macroeconomic on Islamic stock prices: Evidence from Indonesia. KnE Social Sciences, 499-509.
Maysami, R. C., & Koh, T. S. (2000). A vector error correction model of the Singapore stock market. International Review of Economics & Finance, 9(1), 79-96.
Madigan, D., & Raftery, A. E. (1994). Model selection and accounting for model uncertainty in graphical models using Occam's window. Journal of the American Statistical Association, 89(428), 1535-1546.
Min, C. K., & Zellner, A. (1993). Bayesian and non-Bayesian methods for combining models and forecasts with applications to forecasting international growth rates. Journal of Econometrics, 56(1-2), 89-118.
Mishkin, F. S. (2012). The Economics of Money, Banking and Financial Markets (The Pearson Series in Economics).
Moghadam, M. R. & Sezavar, M. R. (2014). Investigating the relationship between macroeconomic variables and the stock market index. Business Review Quarterly, 13(75), 1-12. [In Persian]
Mousai, M., Mehrgan. N. & Amiri, H. (2010). The relationship between the stock market and macro-economic variables in Iran. Economic Research and Policy Quarterly, (54), 73-94. [In Persian]DOI: http://qjerp.ir/article-1-238-fa.html.
Nonejad, N. (2021). Predicting equity premium by conditioning on macroeconomic variables: A prediction selection strategy using the price of crude oil. Finance Research Letters, 41, 101792.
Park, J., & Ratti, R. A. (2008). Oil price shocks and stock markets in the US and 13 European countries. Energy economics, 30(5), 2587-2608.
Peiro, A. (2016). Stock prices and macroeconomic factors: Some European evidence. International Review of Economics & Finance, 41, 287-294.
Pethe, A., & Karnik, A. (2000). Do Indian stock markets matter? Stock market indices and macro-economic variables. Economic and political weekly, 349-356.
Pour'Ebadollahan Kovich, M., Asgharpour, H. & Zolqader, H. (2013). Investigating the relationship between stock prices and exchange rates in oil exporting countries: a co-accumulation approach. Economic analysis of Iran's development, 2(4), 61-86. [In Persian] DOI: 10.22051/edp.2015.2072
Raftery, A.E. (1995). Bayesian model selection in social research (with discussion). In Marsden, P.V., editor, Sociological Methodology, 111-195. Blackwells Publishers, Cambridge.
Rezazadeh, A. (2015). The Impact of Macroeconomic Variables on Tehran Stock Market Returns Volatility: GARCH-X Approach. Quarterly Journal of Applied Economic Theories, 3(2), 121-136. [In Persian]
Rogalski, R. J., & Vinso, J. D. (1977). Stock returns, money supply and the direction of causality. The Journal of finance, 32(4), 1017-1030.
Rohmawati, S., Mutmainnah, M., Asas, F., & Khasanah, U. (2022). Analysis Of The Effect Of The Rupiah Exchange, World Oil Price, World Gold Price On The Joint Stock Price Index In The Indonesia Stock Exchange. International Journal of Science, Technology & Management, 3(1), 153-166.
Samadi, S., Shirani Fakhr, Z. & Davarzadeh, M. (2007). Investigating the effectiveness of stock price index of Tehran Stock Exchange on global oil and gold prices (modeling and forecasting). Quantitative Economics Quarterly (Economic Surveys), 4(2 (consecutive 13)), 25-52. [In Persian]
Sheikh, U. A., Asad, M., Ahmed, Z., & Mukhtar, U. (2020). Asymmetrical relationship between oil prices, gold prices, exchange rate, and stock prices during global financial crisis 2008: Evidence from Pakistan. Cogent Economics & Finance, 8(1), 1757802.
Smith, G. (2001). The price of gold and stock price indices for the United States. The World Gold Council, 8(1), 1-16.
Suhartini, C. D., & Widoatmodjo, S. (2022, May). The Influence of Interest Rates, Exchange Rates, and Money Supply on Jakarta Composite Index (JCI). In Tenth International Conference on Entrepreneurship and Business Management 2021 (ICEBM 2021) (pp. 26-29). Atlantis Press.
Singh, T., Mehta, S., & Varsha, M. S. (2011). Macroeconomic factors and stock returns: Evidence from Taiwan. Journal of economics and international finance, 3(4), 217.
Thakolsri, S. (2021). Modeling the relationships among gold price, oil price, foreign exchange, and the stock market index in Thailand. Investment Management and Financial Innovations, 18(2), 261-272.
Wang, X. (2011). Relationship betwiin stock market volatility and macroeconomic volatility: evidence from China.
Zellner, A. (1986). On assessing prior distributions and Bayesian regression analysis with g-prior distributions. Bayesian inference and decision techniques.
Zeranjad, M. & Motamedi, S. (2011). Investigating the relationship between macroeconomic variables and total stock price index in Tehran Stock Exchange. Economic Research Quarterly, 12(46), 101-116. [In Persian]