Given any cubic or quartic equation with real coefficients, it can be transformed by a change of variable into a standard form, and thus solved by means of a double-sided scale (Fig. 1) in the case of ...

In a transformation model h(Y) = X'β + ε for some smooth and usually monotone function h, we are often interested in the direction of β without knowing the exact form of h. We consider a projection of ...

Intended for students whose background in basic algebra is current. Topics covered include: linear equations, slope of a line, quadratic equations, functions, transformations, inequalities, curve ...