What are some common mistakes people make when working with data?

We don’t just work with data. We socialise with data, we go to the cinema with data, and we have dinner with data on date night. We are surrounded and influenced by data 24/7, not just 9-5. The mistake we make at all hours is blindly accepting numbers. When we see an interesting statistic, we memorise it so next time we are at a cocktail party we can say, “Gee, Larry, did you know that 75% of people are scared of public speaking?”To become data literate, one of the first questions we need to make a habit of asking is: “Where did this number come from?” From there we can look into the research methodology, and whether anyone else obtained the same result.The public speaking statistic is interesting because public speaking and TED coaches slap it on their homepages like stickers on a hipster’s laptop. Where did they find the statistic? Wikipedia. Where did the Wikipedia contributor get the statistic? From an expensive communication journal where the author merely estimated that 75% of people are afraid of public speaking.Many convincing statistics are really just estimates. Yet we accept them as absolute truths and spread them around until they become ‘common knowledge’.Asking, “Where did this number come from?” Must become a reflex. If Pavlov gets his bell out and says he will ring it the recommended 57 times, don’t just salivate, blurt: “Where’d you get that number from Pavlov?”When you become aware of this mistake, and start to question where numbers have come from and whether you are content with how the numbers were arrived at, you can start to become data literate 24/7.-Matt Parker