تأثیر تنوع کسبوکار بر عملکرد بنگاه یکی از پژوهشهای مهم در مورد عوامل فاندامنتال محسوب میشود. به همین دلیل است که در کشورهای مختلف دنیا پژوهشهای متعددی در این حوزه انجام شده است؛ اما معدود مطالعههای انجامشده در کشور، با مسائل و محدودیتهایی مواجه بودهاند. این پژوهش از دو جهت اصلی با پژوهشهای پیشین متمایز است. اولین تمایز در نحوه طبقهبندی کسبوکارهاست که در محاسبه میزان تنوع تأثیر دارد. دومین تفاوت عمده این است که برخلاف پژوهشهای گذشته، بر ارزش بازار بنگاه بهعنوان شاخص عملکرد تمرکز شده است. اطلاعات شرکتهای صنعت پتروشیمی بین سالهای 1388 تا 1392 مبنای پژوهش قرار گرفت و از رگرسیون و تحلیل همبستگی برای بررسی تأثیرگذاری تنوع استفاده شد که در نتیجه آن، اثر منفی تنوع کسبوکار بر ارزش بنگاه که «کسر تنوع» نامیده میشود، مشاهده شده است؛ علاوه براین، دو نتیجه دیگر نیز حاصل شده است: نخست، شواهدی مبنی بر احتمال تأثیر عوامل اقتصاد کلان بر بروز کسر یا صرف تنوع وجود دارد. دوم، به دلیل وجود همبستگی میان تنوع با عوامل افزاینده ارزش بنگاه، ممکن است تحت تأثیر شرایط، تأثیر این عوامل غلبه یافته و در مجموع موجب صرف تنوع شود.
Berger, P. G., & Ofek, E. (1995). Diversificationâs effect on firm value. Journal of Financial Economics, 37(1): 39-65.
Bernardo, A., Chowdhry, B., Palia, D., & Sernova, E. (2000). Real Options and the Diversifcation Discount. Working Paper, 63(2): The Anderson School at UCLA.
Campa, J. M., & Kedia, S. (2002). Explaining the Diversification Discount. The Journal of Finance, 57(4): 1731-1762.
Didar, H. , Imani Barandagh, M. & Shahrezaii, S. (1393). Effect of Business Diversification on performance and Value of Tehran Stock Exchange companies. Asset Manangement and Financing, 2(2): 65-86.
Doaii, M. , Zamani Sabzi, M. & Salehi, H. R. (1393). Effect of Corporate Diversification on Effeciency of Tehran Stock Exchange Companies. Quarterly Journal of Securities Exchange, 7(25): 5-23.
Fleming, G., Oliver, B., & Skourakis, S. (2003). The valuation discount of multi-segment firms in Australia. Accounting and Finance, 43(2): 167â185.
Ghorbani, A. (2013). A study on effect of corporate diversification on information asymmetry using Bid- Ask: evidence from Tehran Stock Exchange. International Research Journal of Applied and Basic Sciences, 5(5): 618-622.
Graham, J. R., Lemmon, M. L., & Wolf, J. (2002). Does Corporate Diversification Destroy Value? The Journal of Finance, 57(2): 695-720.
Harris, M., Kriebel, C. H., & Raviv, A. (1982). Asymmetric information, incentives and intrafirm resource allocation. Management Science, 9(1): 604-620.
He, X. (2009). Corporate Diversification and firm Value: Evidence from Post-1997 Data. International Review of Finance, 9(4): 359-385.
Hyland, D. C., & Diltz, D. J. (2002). Why firms diversify: an empirical examination. Financial Management, 31(1): 51-81.
Jensen, M. C. (1986). Agency costs of free cash flow, corporate finance, and takeovers. American Economic Review, 76(2): 323-329.
Khanna, T., & Palepu, K. (2000). Is Group Affiliation Profitable in Emerging Markets? An Analysis of Diversified Indian Business Groups. The Journal of Finance, 55(2): 867-891.
Lamont, O. A., & Polk, C. (2001). The Diversification Discount: Cash Flows Versus Returns. The Journal of Finance, 56(5): 1694-1722.
Lang, H. P., & Stulz, R. M. (1994). Tobin's q, Corporate Diversification, and Firm Performance. Journal of Political Economy, 102(6): 1248-1280.
Lee, K., Peng, M. W., & Keun, L. (2008). From diversification premium to diversification discount during institutional transitions. Journal of World Business, 43(1): 47â65.
Lewellen, W. G. (1971). A pure financial rationale for the conglomerate merger. Journal of Finance, 26(2): 521-537.
Lins, K., & Servaes, H. (1999). International Evidence on the Value of Corporate Diversification. The Journal of Finance, 54(6): 2215-2239.
Lins, K., & Servaes, H. (2002). Is Corporate Diversification Beneficial in Emerging Markets? Financial Management, 31(2): 5-31.
Mansi, S. A., & Reeb, D. M. (2002). Corporate Diversification: What Gets Discounted? The Journal of Finance, 57(5): 2167-2183.
Meyer, M., Milgrom, P., & Roberts, J. (1992). Organizational prospects, influence costs, and ownership changes. Journal of Economics and Management Strategy, 1(1): 9-35.
Myerson, R. B. (1982). Optimal coordination mechanisms in generalized principal-agent problems. Journal of Mathematical Economics, 10(1): 67-81.
Nanda, V., & Narayanan, M. P. (1999). Disentangling Value: Financing Needs, Firm Scope, and Divestitures. Journal of Financial Intermediation, 8(3): 174-204.
Nayyar, P. R. (1993). Stock market reactions to related diversification moves by service firms seeking benefits from information asymmetry and economies of scope. Strategic Management Journal, 14(8): 469-591.
Nikoomaram, H. & Hadian, S. A. (1392). Explaining the position of debt and corporate diversification in profit management. Journal of Financial Accounting and Auditing, 5(20): 1-28.
Schoar, A. (2002). Effects of Corporate Diversification on Productivity. The Journal of Finance, 57(6): 2379-2403.
Scott, J. T. (1982). Multimarket Contact and Economic Performance. The Review of Economics and Statistics, 64(3): 368-375.
Servaes, H. (1996). The Value of Diversification During the Conglomerate Merger Wave. The Journal of Finance, 51(4): 1201-1225.
Sheikh, M. J. , Zamani Gandomani, M. & Mohajerani, M. (1393). Business Diversification Influence on Financial Performance of Tehran Stock Exchange Companies. Journal of The Accounting and Auditg Research, 6(22): 110-123.
Shleifer, A., & Wishny, R. W. (1992). Liquidation Values and Debt Capacity: A Market Equilibrium Approach. The Journal of Finance, 25(1): 1343-1366.
Stein, J. C. (2013). Agency, Information and Corporate Investment. In G. M. Constantinides, M. Harris, & R. Stulz, Handbook of the Economics of Finance: 146-147). Elsevier.
Stulz, R. M. (1990). Managerial discretion and optimal financing policies. Journal of Financial Economics, 26(1): 3-27.
Teece, D. J. (1980). Economies of scope and the scope of the enterprise. Journal of Economic Behaviour and Organization, 1(3): 223-247.
Teece, D. J. (1982). Towards an economic theory of the multiproduct firm. Journal of Economic Behaviour and Organization, 3(1): 39-63.
Tehrani, R. & Ahmadian, H. V. (1385). Relation between product diversification with stockâs risk and return in Tehran Stock Exchange production companies. Iraninan Journal of Trade Studies, 10(38): 187-212.
Tehrani, R. , Babaii Zaklili, M. A. & Karimi, K. (1387). Effect of Diversification Strategy on financial performance of production companies in Tehran Stock Exchange. Journal of Financial Research, 9(4): 21-40.
Villalonga, B. (2004). Diversification Discount or Premium? New Evidence from the Business Information Tracking Series. The Journal of Finance, 59(2): 479-506.
Weston, F. J. (1970). The nature and significance of conglomerate firms. St. Johnâs Law Review, 44(5): 66-80.