a local vote could have been won with just 1,703 extra votes bought.

Other votes were for titles like best auto repair shop, best bakery or “tradie of the year in Australia”. There was also a census on how many New York City residents wanted to go on a date with a certain model. There were votes on temple photography, the best fintech firms, music mixes, the best female vocalists, several contests about the ranking of attractive persons, a vote on XXL Magazine, a vote on the best local charter flight provider, and so on. Some of these were clearly promoting a product or a performer or artist; others seemed to be clearly what we will call vanity-promotion.

The purchased votes ranged from dozens to about 1,000 at a time. It is hard to assess the overall efficiency of such campaigns, but it can certainly be said that for local contests, where the maximum number of people voting is expected to be measured in hundreds or thousands, it is very easy to rig contests this way, as it would cost only a few dollars.

Search and engage tasks {#Sec:search}
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The common feature of these kinds of microtasks seems to 