You can measure the likelihood that the profile the datasets are similar by chance. For an example simple increasing tendency—correlation that is—that can be explained by coincidentially similar increasing tendency, but if there’s an complex profile to correlation, you can measure what the likelihood for a coincidence is? Even further, the more complex the profiles are, the less likely a coincidence becomes? ( if they match )
Oh well I think I can answer the question:
You can measure the likelihood that the profile the datasets are similar by chance. For an example simple increasing tendency—correlation that is—that can be explained by coincidentially similar increasing tendency, but if there’s an complex profile to correlation, you can measure what the likelihood for a coincidence is? Even further, the more complex the profiles are, the less likely a coincidence becomes? ( if they match )