"Religion Makes People More Generous"- according to The Daily Telegraph's interpretation of a new BBC poll on charitable giving. Tim Harford investigates whether there is a link between practising a religion and whether we give. Plus: Big data - the hype says it will help deliver everything from increased corporate profits to better healthcare but are we being blinded to basic statistical lessons learned over the past two hundred years? And it feels like a huge coincidence, but you only need 23 people to have a better than even chance of meeting someone with the same birthday. This is the birthday paradox, and the best place to look for proof is the World Cup, where 32 squads of 23 players provide an ideal data-set. Alex Bellos crunches the numbers for us.