Invalid Wines and Pudding Powders

The Magic Pudding

This commentary reflects on the contribution of this editorial and its “Three Challenges That Global Health Networks Face” to the totality of the framework developed over the past decade by Shiffman and his collaborators. It reviews the earlier works to demonstrate that the whole is greater than the sum of the parts in providing a package of tools for analysis of network effectiveness. Addition...

The Pudding of Trust

In this essay, we poke at several sacred cows (even though we like their milk and drink it ourselves) and point out several overlooked ordinary cows as well. We discuss our little herd of claims in five sections. Trust— " reliance on the integrity, ability, or character of a person or thing " 1 —is pervasive in social systems. We constantly apply it in interactions between people, organizations...

Invalid Recipes

Proofs of Work and Bread Pudding

We formalize the notion of a proof of work (POW). In many cryptographic protocols, a prover seeks to convince a verifier that she possesses knowledge of a secret or that a certain mathematical relation holds true. By contrast, in a POW, a prover demonstrates to a verifier that she has performed a certain amount of computational work in a specified interval of time. POWs have served as the basis...

Invalid measurement validity.

Concurrence looks at how a measure relates to a gold standard. If, as frequently occurs, there isn’t one, the next best is the correlation with other established measures. This assumes that the latter are themselves valid, which may not be true, and risks stifling innovation, a source of concern if a paper is criticized on this ground. More straightforwardly, concurrence also means that a test ...