« Know your data 32: location data from mobile apps | Main | Reading Statistical Analytics Illustrated »


Feed You can follow this conversation by subscribing to the comment feed for this post.


"...we know that this subset is not represented in these vaccine trials."

I was thinking about this myself awhile ago. The participants of a clinical study are randomly assigned a treatment and control, but the participants themselves are not randomly recruited, they are self-selected. So they're not really "randomized". It makes sense that most of the placebo group would go on to get the vaccine; the anti-vax or vax-hesitant are much less likely to sign themselves up for a clinical trial, I imagine.

I guess this means that clinicians need to apply some form of sampling bias correction, even for "randomized" trials, if they aren't already.

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Your comment could not be posted. Error type:
Your comment has been saved. Comments are moderated and will not appear until approved by the author. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.


Post a comment

Comments are moderated, and will not appear until the author has approved them.

Your Information

(Name is required. Email address will not be displayed with the comment.)

Get new posts by email:
Kaiser Fung. Business analytics and data visualization expert. Author and Speaker.
Visit my website. Follow my Twitter. See my articles at Daily Beast, 538, HBR, Wired.

See my Youtube and Flickr.


  • only in Big Data
Numbers Rule Your World:
Amazon - Barnes&Noble

Amazon - Barnes&Noble

Junk Charts Blog

Link to junkcharts

Graphics design by Amanda Lee

Next Events

Jan: 10 NYPL Data Science Careers Talk, New York, NY

Past Events

Aug: 15 NYPL Analytics Resume Review Workshop, New York, NY

Apr: 2 Data Visualization Seminar, Pasadena, CA

Mar: 30 ASA DataFest, New York, NY

See more here

Principal Analytics Prep

Link to Principal Analytics Prep