While attitudes and beliefs are slow to change, ideology can be influenced by events. A student might leave college with a liberal ideology but become more conservative as she ages. A first-year teacher may view unions with suspicion based on second-hand information but change his mind after reading newsletters and attending union meetings. These shifts may change the way citizens vote and the answers they give in polls. For this reason, political scientists often study when and why such changes in ideology happen, and how they influence our opinions about government and politicians.