Pump ‘n’ dump spam

Laura Frieder and Jonathan Zittrain: “The average investor who buys a stock on the day it is most heavily touted and sells it 2 days after the touting ends will lose approximately 5.5%. For the top half of most thoroughly touted stocks, … a spammer who buys at the ask price on the day before unleashing touts and sells at the bid price on the day his or her touting is the heaviest will, on average, earn 5.79%.”

Leonard Richardson has a site which monitors daily stock spam activity. You can see from his charts that buying these scammy penny stocks is a guaranteed way to lose money.

Leonard, by the way, is the co-author of Ruby Cookbook, 906 pages of shiny, nearly perfect Ruby code with detailed explanations of everything, this book is a fantastic way to learn Ruby.

His wife works at Fog Creek Software; if you’ve emailed us lately and heard back from someone named Sumana, that’s her.

About the author.

I'm Joel Spolsky, co-founder of Trello and Fog Creek Software, and CEO of Stack Overflow. More about me.