Generate a Power Link Object
DESCRIPTION:
Creates a parametrized link subfamily with up to five components: name, link, inverse, deriv, and initialize. The value of each component depends on the value of lambda.
USAGE: 
power(lambda=1)
OPTIONAL ARGUMENTS:
lambda:
The power parameter, which can be any numeric value (typically within 3 units of zero).
VALUE:
A power link object, which is a list of functions and expressions. Type power() for an example. The value 0 for lambda is a limiting case, and results in the log link function; power detects this situation.
DETAILS:
If lambda is less than zero, it is taken as zero (implies log link).
SEE ALSO:
glm , gam , robust , family .
EXAMPLES: 
glm(formula, family=quasi(link=power(1/3)))
quasi(link=power(1/3))
quasi(link = power(0))[c("name","link","inverse","deriv","initialize")]