許多學者認為，持續地產品創新是幫助公司面對競爭環境的一項重要策略，而產品創新需要與其相關的技術基礎作為後盾，因此企業將其技術基礎多角化將會有較好的創新績效。但是，也有學者認為，技術專業化可因學習效果與核心技術之間的知識移轉而提高規模經濟效果，因此，將技術集中在某些技術範圍的公司可因研發活動專業化而獲利，並且使得公司獲得相對技術優勢。在這個假設之下，技術集中化公司的創新績效會比技術多角化公司來的高。看來學者對於哪一種技術策略會有較好創新績效並沒有一致的看法。
本研究以138家台灣上市電子工業公司作為研究樣本，並蒐集中華民國專利公報資料庫、台灣經濟新報資料庫以及台灣經濟研究院產經資料庫等次級資料，以可數追蹤資料進行負二項迴歸進行研究。探討技術多角化對創新績效、技術折損的影響，並加入相對研發強度與產業競爭程度兩個調和變數，深入探究此兩個調和變數對技術多角化與創新績效、技術折損之關係的調和作用。
研究結果顯示，技術多角化對創新績效與技術折損均有正向顯著性的影響。相對研發強度對技術多角化與技術折損之關係具有正向調和作用，而產業研發強度則對技術多角化與創新績效之關係具有負向調和作用。

The concept of building business portfolios emerged in the late 1950s and evolved through the 1970s to become an established planning tool. Early applications of portfolio management balanced resource allocation between business units. In the 1980s and 1990s, companies extended the use of portfolio management into new product selection and R&D resource allocation.
Technology-based firms are faced with the never-ending task of creating new source of advantage as their competitive and market environment shifts. Continuous product innovation can provide a key role in strategies of firms competing in these environment, and when firms diversify their technological base are likely to benefit from new technological possibilities. Additionally, the growing competition （especially in highly innovation markets）, technological change, and the rate of imitation are source of economic depreciation or obsolescence for the firm’s technology.
This article examines the effects of technological diversity on innovation performance and technology depreciation. Comprehensive secondary data on 138 Taiwanese firms in IT sector was collected to test the hypotheses and the result shows that both innovation performance and technological depreciation were positively related with technological diversity. Moreover, relative R&D intensity positive moderate the effect of technological diversity on technological depreciation, on the other hand, industry competition negatively moderate the effect of technological diversity on innovation performance.

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