Tricky topics - validity trickier than reliability. At it’s core I believe reliability is about getting the same results given the same conditions and validity is about measuring what you intend to measure. Harder than it sounds.

Understanding reliability and validity

And straighter hair is rounder. You can demonstrate this with a strand of you hair by gripping it between the nails of two fingers and squeezing all the way down. As you make it oval, you’ll also see it curl.

Apologies to those who caught this earlier. I accidentally posted several in a row and removed them to post one at a time. Really sorry if it disappeared from your blog, and thanks for sharing.

Curly hair is oval

Little technique to try and remember a little more: Will, Still and Fill. HT G Penney

Remember your dreams