How do you explain the differences between the recombinant asci and the parental types answer?

During the process of meiosis (when two genes are linked on the same chromosome) a crossover between these two genes occurs. the result are new recombinant types of gametes. The ratio between parental and recombinant types is always like this: m : n : n : m
where m  parental types and 'n' is recombinant types, and 'm' > 'n'. 
Parental type offspring have the same phenotype as the original parents,while  recombinant offspring have a new phenotype not seen in either of the parents.