The Birthday Paradox
By Dr. Cecil Swetland
The Birthday Paradox is an interesting problem to consider. How many people would need to be in a room together for a 50% chance that two people would share a birthday?
Many would guess that you would need about 183 people in the room to achieve a 50% likelihood that two people would share the same birthday (365 days in a year, divided by two, rounded up to 183 people). It’s not a bad guess, but it’s nowhere near correct.
The answer is 23 people. If 23 people are in a room, there is a 50% chance that two of them share a birthday. If we invite a few more friends and get 75 people in the room, there is a 99.9% chance that two will share a birthday. The answer involves mathematical exponents and probability, as explained in this video.
Humans are not naturally good at projecting exponents or predicting the future. This is important to remember during the school year’s last 30-45 days. No doubt, you will say “Farewell” to students graduating from your school with very bright futures, who have solid foundations in their faith in Christ that will carry them throughout their lives. It’s also likely that you are concerned about others that may have no visible evidence that they are interested in being a Disciple of Christ or have spiritual interest of any kind.
Consider this brief message as a reminder that what appears to be the spiritual trajectory of a student is not always what we see when they are enrolled at our schools. I have two former students in mind as I write this. When they were in school, they could be quite the handful, and I wondered if they would make it across the finish line due to negative attitudes that were more like mockers and scorners than Disciples. However, 15-20 years have passed since their school days. They are now married and raising families. One of them is a godly Pastor who is making a positive spiritual impact on others’ lives daily. The other is a godly woman who is a wife, mom, and entrepreneur. She lives out her faith in Christ every day.
As you prepare to send students onto the next stage of their lives, don’t let the cement dry on your forecast for their futures. The Holy Spirit will continue His work of convicting and convincing. You and I will continue to pray for our students and former students. Undoubtedly, you will be surprised by the amazing transformations that will occur in the lives of our students. For some, it happens after they leave our schools. Don’t let your perspective on their futures prevent you from enthusiastically praying for them and their families. “And I am certain that God, who began a good work within you, will continue his work until it is finally finished on the day Christ Jesus returns.” Phil 1:6 NLT
Let the Birthday Paradox remind you that things are not always as they appear.
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