A number of companies have been recruiting tens of thousands of fake online reviewers to boost sales on e-commerce websites, according to a report broadcast on Singapore’s Mediacorp Channel 5 show Talking Point.

The report revealed that one company was hiring as many as 80,000 people to write positive reviews of products they have never tried for a few hundred dollars each. Major Chinese portal Taobao was named as being affected.

One such ‘fake reviewer’ told a Singapore media site she was earning as much as S$1600 a month for writing reviews about products she knew nothing about.

Nanyang Polytechnic lecturer in data analytics Koh Noi Sian said that based on her research, positive reviews can increase sales by nine per cent, making them the second most influential factor over customer purchase decisions after recommendations by friends and family. She claimed that fake reviews can increase sales to a value of RMB6 billion (S$1.26 billion). She also noted a “very unusual” skew towards positive reviews on Amazon, which claims that over 90 per cent of its reviews are authentic.

Web development director of Oasis Web Asia Simon Yap said online reviews can be analysed on sites such as reviewmeta.com to identify suspicious content such as just-registered accounts, repeated words, and other clues. Such sites, however, do not guarantee definitive results.

Dr Koh advises consumers to source reviews from multiple websites when using them to  consider a purchase.