小編導讀：高頓網校免費題庫，通過針對性地講解、訓練、答疑、模考，對學習過程進行全程跟蹤、專家權威解析與指導，幫助考生全面提升備考效果。　　A portfolio manager is using an exponentially weighted moving average (EWMA) model to forecast volatility for a particular market parameter. What is the implication of an EWMA weighting parameter value of 0.84?
　　A. A greater weight is placed on the most recent change in parameter value than on the previous volatility estimate.
　　B. An equal weight is placed on the previous volatility estimate as on the most recent change in parameter value.
　　C. More information is required to determine the implication.
　　D. A greater weight is placed on the previous volatility estimate than on the most recent change in parameter value.
　　Answer：D
　　The EWMA weighting parameter of 0.84 indicates that a weighting of 0.84 will be placed on the previous volatility estimate and a weighting of 0.16 will be placed on the most recent change in the parameter value.