Recommend a query processing order for the following

queries:

$($i$)($tangerine OR trees$)$ AND $($marmalade OR skies$)$

AND $($kaleidoscope OR eyes$)$

$($ii$)$ tangerine AND $($NOT marmalade$)$ AND $($NOT

trees$)$

$//$ Hint: for a term $t,$ NOT $t$ has an associated estimated

frequency of $N-$ frequency $(t),$ where $N$ is the total number

of documents.

For a conjunctive query, is processing postings lists in

order of size guaranteed to be optimal? Explain why it is$,$ or

give an example where it is not.

Write out a postings merge algorithm, in the style of

Figure $1\mathrm{.}6($page $11),$ for an $x$ OR $y$ query.