With iodide, the solvate $\ce{NaI \cdot 3(CH3)2CO}$ can be formed, in which each $\ce{Na+}$ is coordinated by 6 acetone ligands via oxygen lone pairs, and the $\ce{I-}$ ions fill in the gaps between these octahedral units, being surrounded by the methyl groups of the acetones.
Randomization is a sampling method used in scientific experiments. It is commonly used in randomized controlled trials in experimental research.
Operationalization is the development of specific research procedures (operations) such as survey questions, experimental protocol, interview schedules, observation protocol, etc., that result in empirical observation representing those concepts in real world.