Sentence:  The difficulty of analysis of any subsystem in the phonology is an <WSD>inverse</WSD> function of the size - smaller systems are more troublesome - for any given degree of morphophonemic complexity . 
Meaning of the word marked with <WSD> tags:  a function obtained by expressing the dependent variable of one function as the independent variable of another; f and g are inverse functions if f(x)=y and g(y)=x