Tokyo--Jan. 18--The Nikkei 225 Stock Average closed 1.5% higher, encouraged by overnight Nasdaq gains. Downside concerns were eased on hopes that the dominant Liberal Democratic Party will create some effective steps to support the stock market. The Nikkei was higher for the fifth consecutive trading day for the first time since Nov. 24, 1999, closing at 13,873.92, up 206.29 points.