英文文献：International Portfolio Performance And Diversification Benefits Of Real Estate Investment Trusts In Selected Countries-房地产投资信托基金在选定国家的国际投资组合表现和多元化收益
英文文献作者：Osasumwen Edionwe,Olusegun Ogunba,Olusegun Olanrele,Kola Akinsomi
英文文献摘要：
PURPOSE: Indirect African property investments have largely been left out of international investment portfolios due largely to lack of empirical data (Akpan & Ogunba, 2015). This study attempts to provide some performance data which might stimulate more indirect African investment. It examines the return, risk, risk adjusted performance, diversification benefits and efficient frontier of a 4-aset portfolio of REITs which include an African country (Nigeria), and selected countries from other continents (Malaysia, USA and UK).DESIGN/METHODS FOLLOWED/APPROACH: First, the paper calculated the returns, risk and risk adjusted returns (return to risk and coefficient of variation) of the assets. Second, the paper employed Mean variance analysis to determine the efficient frontier. Third, diversification benefits of each country’s REITs in the four asset portfolio were determined. The approach in doing this was to create five scenarios: The first scenario was an unconstrained set of efficient combinations of the four assets. The four other scenarios involved a sequential exclusion of one country’s assets at a time, creating constrained sets of efficient combinations of 3 of the four assets. The highest return to risk ratio and lowest coefficient of variation of each of the constrained sets were compared with corresponding ratios of the unconstrained set to determine return enhancing and risk reducing benefitsFINDINGS: The African REITs (N-REITs) were shown to perform well on most indicators and not so well on others. It provided the lowest risk of all the four REIT assets and one of the highest risk adjusted returns. Though it provided lower (zero) return enhancing benefits relative to US and Malaysian REITs, it also provided lower (zero) risk increasing effects. The efficient frontier demonstrated that risk adverse investors should invest as high as 49.187% in N-REITs.PRACTICAL IMPLICATIONS: There is considerable potential for investing in African (in this case, Nigerian) REITs.ORIGINALITY/VALUE OF WORK: The paper is probably the first to consider the inclusion of African REITs in international REIT portfolio.

目的:由于缺乏经验数据，非洲间接房地产投资在很大程度上被排除在国际投资组合之外(Akpan & Ogunba, 2015)。这项研究试图提供一些可能刺激更多非洲间接投资的业绩数据。它检验了4-aset投资组合的回报、风险、风险调整绩效、多样化效益和效率边界，其中包括一个非洲国家(尼日利亚)，以及从其他大洲选择的国家(马来西亚、美国和英国)。设计方法:首先，计算资产的收益、风险和风险调整收益(风险收益和变异系数)。其次，采用均值方差分析确定有效边界。第三，确定各国REITs在四种资产组合中的多元化收益。这样做的方法是创建五个场景:第一个场景是四种资产的无约束的有效组合。其他四种情况涉及一次连续排除一个国家的资产，创建四种资产中三种有效组合的受限集。最高回报的风险率和变异系数最低每个约束集的比较与相应的无约束集的比例来确定返回提高和风险减少benefitsFINDINGS:非洲的房地产投资信托基金(N-REITs)被证明在大多数指标表现良好,不太好。在所有四种房地产投资信托基金资产中，它的风险最低，经风险调整后的回报率最高。虽然与美国和马来西亚的reit相比，它提供了较低的(零)提高回报的收益，但它也提供了较低的(零)风险增加效应。有效边界表明风险逆向投资者对n - reit的投资应高达49.187%。实际影响:投资非洲(这里指尼日利亚)房地产投资信托基金的潜力相当大。工作的原创性/价值:这篇论文可能是第一个考虑将非洲REIT纳入国际REIT投资组合的论文。