Lose the obscurity in the lessons and it’s easier to apply them without learning the hard way. However, we’re stubborn. Some things are never going to come through a lesson no matter how obvious or subtle, some things we just need to figure out the hard way.

]]>GayleRN had described a 6th grade teacher using a discrete set of data points. Therefore, I was limiting my explanation of average to discrete points. I wasn’t attempting to describe every thing called an “average.” Average velocity, for example, is really a rate of change in the distance (displacement) over time.

And I see “average” used all the time for median; I don’t see mode used much at all. Sometimes the type of central tendency used will be noted in the footnotes, sometimes you have to delve into the details of the study to determine what method was used.

]]>There are still only 3 types of “average”, or central tendency to be more proper: mean, mode, median.

There are different types of means, like a few you mentioned, as well as different types of medians. So the geometric mean is really just a subset of mean.

General info for all

Statistics are very difficult to understand due to numerous interpretations possible from the data. Johanna’s post listed 5 different ways to obtain an average, and 90% of documents I read never state (neither explicit nor implicit) how that was obtained. Other times, arithmetic mean would be used instead of median because it looks better or vice-versa.

I’m not going to even bother into whether an answer you get is statistically relevant, because I’m an engineer and I frequently get into heated arguments with my colleagues even we have issues with statistics.

]]>“…most of the skills that a person uses in a financially, professionally, and personally successful life are developed outside of a classroom.” Maybe personally, but not financially or professionally. I think you’re taking your school learning for granted. If I could not read or do math, my financial life would be a joke. If I had not learned to follow a schedule, do what other people want, work for high quality, write well, and think critically, like I learned in in school, my professional life would be a joke.

“The fundamental key to money management is to simply spend less than you earn every single month.” – Not for me, it’s not. For example, I plan to pay cash for my next car, and that month I will be spending far, far more than I earn. It’s better to spend less than you earn on average while maintaining good cash flow (with savings). (By “average” I mean the mean–all the spending and earnings matter.)

Many of these categories boil down to seeing another person’s point of view. I’d break that down into two categories – a) understanding that other people are like us and doing the best they can and b) understanding that other people are different from us and so things that make sense or are obvious to us may not be so from their perspective.

]]>Workarounds for dealing with the a**holes in your life and on your job.

Argue with a liar, and you get more lies. Persuade the corrupt, and they merely tell you what they think you want to hear, then continue their corrupt ways. They will ignore honest figures, or fudge them.

My tuition money’s here and waiting. Go for it.

]]>I don’t think I’ve ever seen a median or mode called simply the “average” – usually, when somebody’s presenting statistics, they use “average” to mean the mean (or “arithmetic mean”), where you add up all the numbers and divide by the number of numbers. If they’re talking about the median or mode, they’ll call it the median or mode.

But in colloquial speech, “average” means something more like “typical,” so the median and the mode are a lot closer to people’s intuitive idea of what an “average” should be. So you get people concluding that all statistics are nonsense when they hear things like how the average household has 2.5 people and owns 0.8 homes. The statistics are not nonsense, of course, but they might not mean what the average person thinks they mean.

]]>What you are describing is the median, which is one type of average. There are really three types of “averages”: the mean, the median, and the mode. The mean is what you obtain by summing the values and dividing by the number of values; it’s what most people think the definition of average is. The mode is the most frequently occurring number in the set of data. The median is the number in the middle of the set of data.

This is why you need to be careful when statistics list an “average” value. Is it the mean, the median, or the mode? Each has their advantages, and they can be wildly different.

]]>In the mornings, I work in non-profit civic engagement. In the afternoon, I teach middle school. The ability to multitask, to keep 5 or 6 things balanced in my head at once, doing 1-3 at a time, is essential to success in both parts of my job. In fact, every job I’ve had by copying editing has required a deep level of multitasking.

I’ve known far too many people who can’t multitask. Just can’t. At all. That’s a skill that needs more practice than closing other web browsers so we can exclusively focus on this blog.

]]>Once you get to a high enough level in your major, the default assumption is that you know what you’re talking about, and the default grade is A. (At least, this was true for me in physics, which is notorious for being one of the fields least prone to grade inflation.) You’ll only be singled out for criticism or have your papers marked down if the professor catches you saying something blatantly wrong. But if you present your ideas in a big wordy jumble that makes the reader’s eyes glaze over, nobody will notice if you say something that’s not quite right.

This is my theory of why so many otherwise very smart people are so terrible at organizing ideas. Not that I mind so much – if they were better at it, I wouldn’t have a job.

]]>At work I noticed a very impressive graph that announced that a certain performance measurement was up 100%. On closer inspection last month was 0 and this month was 1 event. Statistically irrelevant but used by management to praise or punish.

If you don’t know what is wrong with these 2 scenarios those who do will use you and abuse you.

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