There is an old saying about what assumptions make you and me, but what do assumptions really make?
Assumptions can be powerful. They can make thinking and planning easier. They can also help us get things wrong and make things worse than they already are.
Assumptions make things easier
Assumptions allow you to set bounds on things, on what is happening and what you should do about it. They make things easier because you can say “as long as this assumption (assumption) is true we can do this (technique or action)”.
Assumptions save you time in that you don’t have to filter through all the possibilities and all the situations that might be going on. That works great as long as the assumption is actually true…
Assumptions are based on a lot of things. Many assumptions are based on surface details. Many assumptions are made on what usually happens, and what things usually mean. They may be made on the basis of empirical tests and research, or anecdotal evidence and personal experience/opinion. Often they are rational. Sometimes they aren’t.
Assumptions make things worse
Maybe it would be more correct to say: not verifying your assumptions makes things worse.
Rational or not, an assumption allows you to say “this is what this means 99% of the time; therefore, 99 times out of a hundred this is how I should respond.” The problem is 99% isn’t 100% (and if you think your assumption is true 100% of the time you have either done something to cause it to be true 100% of the time, or your assumption is faulty). If your assumption isn’t true you can be headed for problems.
This happened to me last year when some hospital folk saw a fat guy walk in with what turned out to be a new diabetes diagnosis. Several people assumed it was an old diabetes diagnosis and I was just an idiot who wasn’t taking his meds or following his doctor’s instructions (wrong!). That led to several patient care and treatment issues… It happened to a cousin of mine when she and her family assumed they were talking about the same airport. She landed at LAX and they were waiting in San Diego. It happened to a whole boat load of people when the crew of the RMS Titanic assumed their ship was really unsinkable and plowed into an iceberg.
People sometimes cling to their assumptions even though there is evidence that warns them the situation is different, or that the assumption is wrong. I personally have watched people make major goofs because of an assumption, even though the person they were just talking to told them not to do it (I may have done this a time of two myself, but I try not to…).
So there is our answer. The old saying about what assumptions make you and me can be true. Our assumptions can make for big (and expensive) goofs. But, they can also make our lives easier and our decisions more efficient.
So, the next question is what do we do about it?
Our assumptions can be a useful tool. We just need to check that they reflect the reality we’re dealing with.
In the field of statistics we have a lot of tests that have basic assumptions. We also have tests to verify whether the assumptions are met or not, and research that demonstrates how far we can push the assumptions of our tests. We can and should check that our assumptions are accurate before we drag out the old ANOVA, MANOVA, EFA, CFA, SEM or whatever tool we’re going to use.
In life it gets a bit messier. The field of Statistics is meant to be rather objective and empirical. In life egos and other realities can get in the way, and there are a lot less well documented way to test our assumptions. The good news is there are a couple of things that we can do…
- Listen: Actually listening to what people have to say rather than trying to jump ahead in the conversation; figure out your response; or waiting till the noise goes away, can have a big effect on our ability to get things right. Even my neighbors three year old can come up with something I’ve missed once in a while.
- Look: Often we use assumptions to save time. That can be useful, but we shouldn’t try to save that time in the arena of actually looking at what’s in front of us (literally or metaphorically). Again this is a case of don’t be in such a hurry that you miss the information. Often warning signs will be there (like that iceberg or your check engine light…), but if we ignore them they can’t help us.
- Be willing to be wrong: None of us like to be wrong (well most of us don’t). Unfortunately you sometimes have to be wrong before you can be right. There is a natural tendency called confirmation bias that can lead to cherry picking the information that supports what you’ve already assumed or decided, and leaving any other information out. We need to learn how to get past this problem. If you are willing to be wrong, and recognize when you’re wrong, you have the ability to fix mistakes and eventually be right (as opposed to the guy who swears he knows where he’s going right up to (and after) he drives off the cliff).
When we listen, look, and are willing to be wrong (and make changes) our assumptions really can help us be more efficient, and right more often. But, we have to learn to verify them and not just depend on them.
That’s it for this one dear reader. Until next time…
(This is a little out of my usual lingo but I like it…) “Check yourself, don’t wreck yourself!”