Categorical Variable: the variable whose values can be put into categories (groups). Cluster Sampling: a researcher divides the population into clusters. Then, a simple random sample of the clusters ...

Producers of infant formula employ comprehensive food safety systems, including product testing to ensure those systems are working. A new study finds that some testing methods are more powerful at ...

Ali Hussain has a background that consists of a career in finance with large financial institutions and in journalism covering business. Vikki Velasquez is a researcher and writer who has managed, ...