"Many Christians are trained to believe that God always answers their prayers. But to challenge that idea, I pose a simple hypothetical question: What if God did NOT answer your prayer? Giving this question serious thought will reveal what you're actually praying for and quickly prompt you to consider clear criteria for an answered vs unanswered prayer. On the other hand, if you cannot come up with an answer to this question, then you're probably trying to obscure your own view of what happens after you pray and what you're even praying for."
Truth conforms with reality. Reality appears to be determined and random by all scientific observations. Science (which is Latin for knowledge, and is JUSTIFIED, true belief) has never accepted a miracle. Prayer attempts to violate these findings. Oh, and "The answer is no" is an unjustified obfuscation.
The video below does a good job in presenting an easy and practical way to test the effects of prayer subjectively: