Heads you lose

I once asked a farmer friend if he was concerned about the long-lasting drought of the time. He wasn’t, he said, because every day the drought went on was another day closer to the drought ending. Real glass half-full stuff.

For normal people, every negative cancer test since their last treatment for cancer is a cause for celebration because it increases the chances that the cancer has gone entirely. Every negative test is more evidence for absence.

For people with anxiety, every negative test is a cause for anxiety because it is another three months closer to the cancer returning. Every negative test increases the chance that the next test will be positive, rather in the way that people think that if you toss a coin and get heads 100 times, then the chance that the next toss will be tails is constantly increasing. Both assumptions wrong of course, each toss of a coin is an independent event with a fifty/fifty chance of heads or tails (but try convincing the addicted gambler of that). Every cancer test is also an independent event (but try convincing the anxious mind of that).

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s