SLOW SEARCHJaime Teevan, Kevyn Collins-Thompson, Ryen White, Susan Dumais and Yubin Kim

Slow Movements

Speed Focus in Search Reasonable

Not All Searches Need to Be Fast• Long-term tasks

• Long search sessions• Multi-session searches

• Social search• Question asking

• Technologically limited• Limited connectivity• Mobile devices• Search from space

Making Use of Additional Time

TIME + SEARCHUnderstand how time influences the search experience

Time in Search: Micro Scale• Impact of sub-second changes in response time• Study using large-scale query log analysis• Natural variation exists within a single query• Measure interaction as f(response time)

• Time to click• Abandonment rate

Small Increases Big Changes

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Page Load Time (ms)

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NavigationalInformational

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Time Spent Searching (mins)

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Page Load Time (ms)

Impact of Sub-Second Changes• Imperceptible changes impact behavior• Impact of slower page load time

• Slower time to click• Increased abandonment

• Some queries more sensitive to time than others• Time impacts navigational queries > informational• Informational queries less impacted by very slow results

Time in Search: Macro Scale• Impact of longer changes in response time• Two user surveys with 1476 participants in total

• Detailed survey with 141 MSFT employees• Online survey with 1335 people

• Asked about the participant’s last search• Willingness to wait for results as f(response time)

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Time Spent Searching (mins)

Last Search Took Minutes or Hours

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Time Spent Searching (mins)

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Time Constraints in Search• Reported spending more time on some searches

• Important tasks• Tasks with a deadline• Tasks with bad search results

• Time constraints• 34% of tasks needed results urgently• 39% of tasks needed results by a deadline• 27% of tasks needed results whenever

Willingness to Wait• Time willing to wait < actual time spent searching• Participants do not trust the search engine

• 28% people said they want “fast results always”• For important tasks

• Spent more time searching than less important• Willing to wait less than less important

Willing to Wait for Quality Results

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Impact of Longer Intervals of Time• People do not want to wait, but…• Report spending a lot of time on important tasks

• 90% of the important tasks took more than 1 minute• 23% of respondents found their results unacceptable

• Are willing wait in some cases• When the results obtained were poor• When a perfect answer is sought

Summary

QUESTIONS?Jaime Teevan teevan@microsoft.com Yubin Kim yubink@cmu.edu