Perhaps you should try some spelling variations:
optimisation algorithm » optimization algorithms, estimation algorithm, estimation algorithms
quantile optimisation » quantile estimation
modified quantile » modified adaptive
df approximation » _ approximation, one approximation, time approximation
modified df » modified _, modified adam, modified bi1

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "(( modified df approximation algorithms ) OR ( modified quantile optimisation algorithm ))~".
• Adding a wildcard symbol may retrieve word variants: (( modified df approximation algorithms ) OR ( modified quantile optimisation algorithm ))*.