from Hacker News

Perfect Example of Data Manipulation

by efojs on 7/5/22, 11:10 PM with 3 comments

There is this article with a title:

"Tattoos and piercings are more common among those who experienced childhood abuse and neglect"

(not going to make a link for them)

What message do you get out of this title? — that most tattooed people were abused in childhood, don't you?

How about their conclusion:

> Results showed that around 40% of participants had at least one tattoo or piercing and approximately 25% of participants reported significant child abuse or neglect. Among the participants reporting child abuse, 48% had a tattoo or piercing, while only 35% of people not reporting child abuse had a tattoo or piercing.

It says that 48% were abused — almost half. Impressive, ha?

However, if you plot what they say, or recalculate, or rebuild the sentence, you get that:

only 12% are tattooed and were abused, and ~35% are just tattooed.

Just saying.

  • by efojs on 7/6/22, 8:26 AM

    Oh, I'm sorry, even now I lied here, but not intentionally:

    > and ~35% are just tattooed.

    ~35% (37% to be exact) not of all respondents, but of those who have tattoos (from those 40%).

    From all respondents it would be 28% vs. 12%.

  • by mtmail on 7/5/22, 11:25 PM

    > Among the participants reporting child abuse, 48% had a tattoo or piercing

    Based on the quoted text I'd read that (union of abuse and tattoo/piercing) as 48%, not 12%.