A Lament

[rrich]

A Lament about numbers.

I am definitely classified as an old phart. There is no question about it as is just one of those things that comes along with age.

I remember getting through high school chemistry and physics by using a battery-less calculator, often called a slide rule. The slide rule was really only accurate to 3 or 4 places but it taught intuition. Anyone who used a slide rule for calculations got that intuitive feel to the correctness of a calculation. Kids today will put the numbers into a computer, calculator or smart phone and accept whatever comes out as precisely accurate. While the math may be precise but entirely based upon the wrong numbers that were input. Misunderstanding or fat fingering could cause the precisely calculated wrong answer.

I was at Costco yesterday and purchased a few items including ink cartridges. I was expecting $60 to $80 and the total was $136, including sales tax. The checkout cashier saw the look on my face and said, "The printer cartridges were $68." I realized everything was correct. Kids today would have just accepted the total, handed over the credit card without a thought as to what the correct total should be.

Unfortunately this intuitive feel or understanding can't be taught but it has to be acquired through practice. Once acquired it stays with you for life.

[Big Shed]

Used to love my cylindrical slide rule.

Had to use log tables before I had a slide rule.

We were taught mental arithmetic from early on in primary school, shock horror, multiplication tables were drummed in to us.

[BobL]

Two significant things I've noticed that modern education fails miserably at is the need for "practice and play" in subjects that require some thinking. The two are closely related but not the same

Practice is obvious, we wouldn't expect anyone to become proficient in a sport or musical instrument without it, so why is it assumed that students can be shown something sightly complex once and they should understand and be able to reproduce it? Practice is essential for students that don't get it quickly and need time to work out what is going on and then to be able to do it quickly.

Play is a combination of practice and open ended exploration. People learn a lot by playing with objects and subjects, sometimes a lot more than they do from a teacher. Play allows students to discover and understand patterns that teachers don't have time to give students. People like playing and in my book a good teacher is essentially play group leader.

A contributor to the lack of play seems to be the scourge of competency based training that often only allows for showing/telling students the basics once.

A example of the need for play is when I taught experimental physics at Uni. In first year the students performed two x 3 hour experiments on the use of oscilloscopes. About 2 of the 6 hours were informational and the rest was play. In the second experimental session two or so the 20 or so knobs on the oscilloscopes were moved so as not to be on their correct positions and the students had to find out which ones they were (they were not all the same knobs). This "real world" test demonstrated whether the students knew what was going on.

When the feds cut back funding per student the Uni Administrators told us we had to reduce student contact. Experimental work went from 104 hours per subject per year to 48 hours per year. Experiments like the Oscilloscope familiarisation was reduce to the informational component (2 hours) so no time for play or the real world test and the result was they performed poorly on assessment of use of this device. If we had assessed them properly we would have failed most of them but there was a policy that required us to pass at least a specific percentage of first year students.

The result of this is of the students who made it into second year few could use an oscilloscope and had to be shown how, If the oscilloscope had a problem they were stuffed and this further impacted on the work being done in the following years.

I did my first degree on a side rule, I got to use my first calculator doing my Dip Ed exams. It was a borrowed calculator and the battery went flat in the middle of the exam. Luckily I had brought along my slide rule as a back up. During my higher degrees I paid a months salary for a programmable HP41CV with a magnetic card reader. What a great little machine - I even had nuclear reactor model running on it. I still have it (rechargeable are stuffed) but it still runs from a mains adapter. Best of all the same calculator is available as an App so I have it with me on my mobile and I use it a lot in the shed.

[rrich]

Ah yes, the silly scope!

In school all we had were the free running version similar to the Heath Kit models. Then I started with the RCA Data Processing division. I was presented with learning to use a "Triggered" oscilloscope. What as difference! It took a few weeks to become proficient.

After about 18 months I went to work for GE. RCA had used the "T" brand and GE used the "H" brand. The "H" brand was mediocre compared to the "T" brand. I would go get the one slower "T" on the test floor. I could bring up a system to running diagnostics in about half the time with the "T" vs. the "H".

It was amazing but the people that acquired the "H" couldn't understand the value of a true DC triggered oscilloscope. I suspect that there was much more to the "H" decision than was visible on the test floor.

[elanjacobs]

Well I'm decidedly not an "old phart", but I made a point of learning how to use a slide rule - mainly because I have 2 watches that have one on the bezel. In primary school, multiplication tables, up to 12, were still being drummed into our heads and in high school we were still being taught how to do polynomial algebra and calculus by hand. Year 11 and 12 maths exams were also in 2 parts, one with a calculator and one without.

I don't know what the education system is like now, but some of us younger folk still do know how to do things the old way and there are usually scribbles on my bench at work to prove it