Perhaps you should try some spelling variations:
estimation algorithms » estimation algorithm, optimization algorithms, optimisation algorithm
parameter estimation » parameter estimates, parameter optimization
higher algorithm » winner algorithm
based higher » btec higher
code based » model based, coal based, income based

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( code based higher algorithm ) or ( modified parameter estimation algorithms ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( code based higher algorithm ) OR ( modified parameter estimation algorithms )).
• Adding a wildcard symbol may retrieve word variants: (( code based higher algorithm ) or ( modified parameter estimation algorithms ))*.