Facebook Autocomplete

Suppose that Facebook (Meta) wishes to implement an autocomplete feature for its search bar that will help users to direct to a page where they will get the result they were looking for.

For example: Instead of writing the whole word, by typing just “ap” a person should get in the autocomplete menu the desired word and then when he/she selects that word it will direct them to any desired page/group/person.

How do you design the auto-complete and how you measure the effectiveness
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Clarifying Questions
What is the main goal of autocomplete ? give users a seamless experience and convenience to use FB?

FB Goal > increase engagement

User Journey
comes to a certain page, goes to the search bar and start typing > chose the one he wanted and proceed

Method formulate a method to see where a user is, and get the context and based on the letter he starts typing, based on historical data, suggest most searched words with that as they type
if they are on FB timeline, show friends, if they are on groups, show posts, if they are on their own profile, show relevant posts and so on build an algorithm to see the context of the page and then match and show the highest probable one take feedback based on their clicks, or the rank, and then use it to get a better-trained model

Measure
% of users using autocomplete
rank of the algorithm based on what they click
% of users used once using again the second time in a week/biweekly
new users vs old users
what sort of users are using
mobile/desktop and android/ios
search aborted in between due to wrong suggestions