In a recent paper, Tiao and Guttman (1967) discussed the use of adjusted residuals to analyze the behaviour in moderate to large samples of the premium and protection of Anscombe's rule (herein designated as theA(k)-rule) when sampling is from theN(μ, σ) distribution, μ is to be estimated;and wherekoutlying observations are suspected of being spurious (k= 1 and 2). A discussion of two other rules, Semi-Winsorization (S(1)-rule) and Winsorization (W(1)-rule), is given in Guttman and Smith (1969, 1971). This paper investigates the behaviour, for moderate to largen, of theA(k)),S(k)) andW(k))- rules,k= 1 and 2. To do this, we define rules based on adjusted residuals, which we shall denote as theAk,SkandWkrules. Expressions for the premium and protection of theSkandWkrules are derived, and contrasted with these characteristics of theAkrule, obtained by Tiao and Guttman (1967).