Firm conclusions about causal connections are difficult without randomly controlled experiments.
When considering the correlates of AOD use, any attempt to discern whether these correlates are causes or consequences of substance use is hampered by three factors: Firm conclusions about causal connections are difficult without randomly controlled experiments.
"It was a beautifully controlled experiment," says Pembrey.
You cannot run controlled experiments in which a particular institution is randomly imposed on some countries, but not on others, in order to compare how they fare.
What works better are "randomized controlled experiments" that compare how randomly sampled voters exposed to an experimental "treatment" (in this case various campaign activities) compare to randomly sampled voters in "control groups" with no such exposure.
Some of these experiments can be controlled experiments in which children are randomly assigned to contrasting treatments and control groups.
That is, controlled experiments.
The results in terms of recall, precision and F1 scores are summarized for S. cerevisiae in Figure 2. Also, shown in the figure are the results of randomly assigned cluster labels as a control experiment.
She looked like a highly controlled oxidation experiment.
A randomised, controlled animal experiment.
