The totally off-topic thread

[Shelf]

I agree. Went back to study at 58, having been an A+ student but not wanting to go the teaching/commonwealth scholarship route. Meandered through work life. Attended TAFE diploma course = Uni Arts degree. Folks in my classes were of all types, a few having to leave school at 15 or so - and spent their whole lives feeling inadequate or plain dumb. We also had kids who'd finished Year 12, and wanting to do a year of study before applying as a mature age student to the courses they missed out on. However the mature aged ones found that simply because of their life experience, a certain amount of wisdom had kind of crept up on them and they did very well indeed. The youngies? Sadly 99.9 disappeared without trace!

I've just completed a diploma. The course had an interesting mix of students from the unemployed to national directors/GM's.

 

[anat0l]

Well if we want to discuss numeracy. I was given a $1 coin yesterday that was label 100 years of Anzac, with a 2014 minting date. As ANZAC happened/started 99 years and almost 2 months ago, I have a minor issue with that coin. It may be the 100th year now, but there will not be 100 years until 25 April 2015. Someone at the mint can't count.

On a related note I was checking out the sample HSC questions when I came across the question below. Now both of the figures shown time varies inversely with speed, ie bigger speed lower time. But apparently only one is the correct answer. :?:

...

JessicaTam has the correct answer. It's a mathematical relationship question; a QLD grade 9 equivalent should be able to answer this.

Well that was a disappointment but still a great game.

NSW 6 Qld 4. ...

Took NSW long enough to finally win a series.

Thanks for the score. Now I can put it to rest without having to check all of the news websites and what not.

I suppose there will be much blue banter and rubbing in faces and so on. Now that the "x years in a row" cheer no longer holds for the Maroons, what will be the campaign cry for the Maroons for next year's attempt?

 

[serfty]

At least it will shut up the one-eyed canetoads at work for a little while....

No it won't - should have been a line drop out rather than a penalty after the kickoff touched a NSW player upon the restart after the try.

A referee Howler if I have ever seen one ...

 

[medhead]

*A is the correct answer - as the speed approaches 0 the time taken to travel the distance approaches infinity.*
I have hidden the answer above for those still thinking about it.

[-]The question doesn't say that the relationship has to be physically correct. It simply asks which figure shows an inverse relationship. There are 2 figures that show and inverse relationship. [/-]

Reading who thought that would be useful.

And was 1st January 2000 actually the first day of the new millennium? The whole world celebrated it then.

Of course not, there was no year 0. Years start counting at 1. But there is not 1 year until the end of the first year.

JessicaTam has the correct answer. It's a mathematical relationship question; a QLD grade 9 equivalent should be able to answer this.

[-]Where does the question ask for the correct physical relationship?[/-]

Or I should read all the words properly.

 

[anat0l]

The question doesn't say that the relationship has to be physically correct. It simply asks which figure shows an inverse relationship. There are 2 figures that show and inverse relationship.

One of them is the inverse (technically "proportionally inverse") relationship.

The other is not; it would be a negative linear relationship. In casual speech it may be called "inverse" but at least in mathematical parlance this would be incorrect.

If we're talking about multiple choice where the instructions almost always say, "Select the most appropriate answer, or the answer which best answers the question," then taking into account the context of describing a car's speed and time it takes to travel a certain distance, then there is one clear correct answer of the two you present.

 

[medhead]

One of them is the inverse (technically "proportionally inverse") relationship.

The other is not; it would be a negative linear relationship. In casual speech it may be called "inverse" but at least in mathematical parlance this would be incorrect.

If we're talking about multiple choice where the instructions almost always say, "Select the most appropriate answer, or the answer which best answers the question," then taking into account the context of describing a car's speed and time it takes to travel a certain distance, then there is one clear correct answer of the two you present.

That's a relief. You need to read the question better as well. Your explanation doesn't cover it at all. The bit I missed was the actual question and that it asked for the figure that shows this relationship. There is only one figure that shows this relationship. No need to hand waving about the figure that best shows the relationship. I mis-read is enough.

Oh but technically C is a proportionally inverse relationship. A is not proportional it is exponential.

 

[woodborer]

Well if we want to discuss numeracy. I was given a $1 coin yesterday that was label 100 years of Anzac, with a 2014 minting date. As ANZAC happened/started 99 years and almost 2 months ago, I have a minor issue with that coin. It may be the 100th year now, but there will not be 100 years until 25 April 2015. Someone at the mint can't count.

It's not the mint, it's the government. They are broadly using the period 2014-2018 as the centenary of the Anzac tradition. (Anzac Centenary - home), matching the wartime period. While the Gallipoli event is a specific event in that, note that the people that were involved in Gallipoli came together in 2014 before leaving Australia.

 

[JohnK]

No it won't - should have been a line drop out rather than a penalty after the kickoff touched a NSW player upon the restart after the try.

A referee Howler if I have ever seen one ...

I did not watch the game so cannot comment. In fact cannot remember the last State of Origin game I did watch.

It is great that the 3rd game is now a dead rubber.

 

[medhead]

I agree. Went back to study at 58, having been an A+ student but not wanting to go the teaching/commonwealth scholarship route. Meandered through work life. Attended TAFE diploma course = Uni Arts degree. Folks in my classes were of all types, a few having to leave school at 15 or so - and spent their whole lives feeling inadequate or plain dumb. We also had kids who'd finished Year 12, and wanting to do a year of study before applying as a mature age student to the courses they missed out on. However the mature aged ones found that simply because of their life experience, a certain amount of wisdom had kind of crept up on them and they did very well indeed. The youngies? Sadly 99.9 disappeared without trace!

Things must have changed a fair bit. Upgrading younglings fresh from school were not considered mature age until 5 years after finishing year 12. It's amazing how much the entrance score increases after 1 year of demonstrating you can pass at a tertiary level.

One of the best physicists I've ever studied with was a mature aged student. Absolutely brilliant. He went back to brick laying because of a lack of post graduate funding.

Does anyone other than a Queenslander care?

At least it will shut up the one-eyed canetoads at work for a little while....

The NSW government seem to care judging by the 10000s of thousands of dollars worth of fireworks they just set off over the harbour.

Anyway the only score that matters is 8-1

It's not the mint, it's the government. They are broadly using the period 2014-2018 as the centenary of the Anzac tradition. (Anzac Centenary - home), matching the wartime period. While the Gallipoli event is a specific event in that, note that the people that were involved in Gallipoli came together in 2014 before leaving Australia.

I don't know about this revisionist history. All I know is that Anzac has been about the Gallipoli campaign in 2015 for as long as I remember.

 

[anat0l]

That's a relief. You need to read the question better as well. Your explanation doesn't cover it at all. The bit I missed was the actual question and that it asked for the figure that shows this relationship. There is only one figure that shows this relationship. No need to hand waving about the figure that best shows the relationship. I mis-read is enough.

Fair enough, you got me on that one. So I misread the question as well. That said, when I was deciding I also tested the answer in my mind by thinking of the car.

Oh but technically C is a proportionally inverse relationship. A is not proportional it is exponential.

No. Inverse proportions of two quantities, x and y, are such that the relationship between the two variables can be described as xy = k for some constant value of k. The only graph which shows this relationship is A.

C is negative linear, i.e. a linear trend but with a negative gradient. It is strictly not an inverse relationship, let alone a proportionally inverse one.

A is not an exponential relationship (e.g. y = exp(x)) since an exponential relationship has a defined value when the independent value is 0. An inverse relationship is technically undefined when the independent variable is equal to 0.

 

[Flashback]

In non-mathematic news ... car just got picked up, chap confirmed that is was the same area as pre-existing damage so all good don't worry about it.

 

[JohnK]

Probation is a necessary tool but must be utilised correctly. I have been involved in initially extending a probation period for an under-performer to give them the best chance to subsequently terminating their employment. A difficult but necessary decision.

In our company the probation period is 3 months. The people they are hiring are not graduates. They are supposed to have experience. In that time you know if someone is going to make it or not.

They are still there 12 months later and still struggling. Some have been there for 4-5 years. They are nursed along. A 16 hour job estimate with a fair bit of contingency is doubled and doubled again because an experienced programmer is incompetent. That is too nice a word. Hopeless. Useless would be more suitable words.

I see this. We see this. It is demoralising on the rest of the people who are doing their job to see this type of attitude from management. I know it is not nice to let someone go but sometimes it is for the best.

But my biggest question is how did they ever get hired in the first place? If I lost my job today and went back on the market it would take a long time for me to get an interview. Why? Because they are hiring these type of people thinking cheap labour is going to do the trick. Not quite.

 

[whatmeworry]

Does anyone other than a Queenslander care?

At least it will shut up the one-eyed canetoads at work for a little while....

No Victorians care...

 

[markis10]

Ahem...: Queenslander!!

Well they are brave. :shock:

 

[JessicaTam]

In non-mathematic news ... car just got picked up, chap confirmed that is was the same area as pre-existing damage so all good don't worry about it.

And I am not starting a maths thread!

 

[medhead]

No. Inverse proportions of two quantities, x and y, are such that the relationship between the two variables can be described as xy = k for some constant value of k. The only graph which shows this relationship is A.

C is negative linear, i.e. a linear trend but with a negative gradient. It is strictly not an inverse relationship, let alone a proportionally inverse one.

A is not an exponential relationship (e.g. y = exp(x)) since an exponential relationship has a defined value when the independent value is 0. An inverse relationship is technically undefined when the independent variable is equal to 0.

Figure C does show an inverse relationship. This is not changed by it being wrong for the situation and wrong at the axis.

As for A, it has a characteristic shaped curve, much like radioactive decay which also never reaches zero. It is not correct to say the value at zero is undefined. The relationship approaches zero but never actually reaches zero. There is no value at zero defined or otherwise.

 

[TheEmu]

...
Someone has to earn below the average. otherwise it wouldn't be an average.
...

Thanks medhead, I don't feel so bad now

Half the people you know are below average...

 

[medhead]

Half the people you know are below average...

Some might say most of the people I know are below average.

 

[rogerkambah]

Things must have changed a fair bit. Upgrading younglings fresh from school were not considered mature age until 5 years after finishing year 12. It's amazing how much the entrance score increases after 1 year of demonstrating you can pass at a tertiary level.

One of the best physicists I've ever studied with was a mature aged student. Absolutely brilliant. He went back to brick laying because of a lack of post graduate funding.

Unfortunately, this is yet another example of our lucky country not using its human resources to the best of their (expensive) education and abilities. I too, have friends like that.

 

[anat0l]

Figure C does show an inverse relationship. This is not changed by it being wrong for the situation and wrong at the axis.

As for A, it has a characteristic shaped curve, much like radioactive decay which also never reaches zero. It is not correct to say the value at zero is undefined. The relationship approaches zero but never actually reaches zero. There is no value at zero defined or otherwise.

Apologies to the collective for continuing the maths thread, but I will push further. And no, this is not objecting for objecting's sake.

Loosely in not-so-strict speech, if one quantity goes up whilst another goes down, people tend to say this is an "inverse" trend. For example, people may say that the price of an article will vary inversely with its supply to the market (i.e. low supply, higher price, and vv.), though in practice this is not necessarily in perfect proportion.

However, at least in strict mathematical speak, and more often than not in scientific circles, there is one definition of 'inverse relationship', which is as I described and is demonstrated in Figure A. This has nothing to do with the specific situation in the question - this is a general definition. Inverse relationships (or strictly "inverse proportion") are not defined ("no value") when either variable is equal to 0.

Figure C is a linear trend; because it has a negative gradient, it is called a negative linear trend.

Figure A does look a lot like the negative exponential trend/curve. That said, one subtle difference between the two curves in question is that a negative exponential does have a defined value when the independent variable is equal to 0. This makes sense, e.g. in your example of radioactive decay, if the radioactive concentration is on the vertical (dependent) axis and time is on the horizontal, then when time = 0, there is a value for radioactive concentration (i.e. the initial concentration). If we attempted to describe this using an inverse relationship, this would be wrong, because there is no defined value at time = 0. The shapes of each of these curves also generally look quite different until the value of the dependent variable approaches 0.

If you get out a graphing program and plot the graphs of y = 1/x (inverse relationship) and y = exp(-x) or y = e[sup]x[/sup] (negative exponential), you'll see that Figure A looks closer to the inverse relationship. The negative linear of Figure C looks more like y = -x, although to produce the graph in Figure C more closely, you would need a vertical shift, i.e. y = -x + k for some positive value of k.

In maths, "not defined" and "no value" are pretty much synonymous. For some reason, however, it is proper to use the term "not defined" for an answer which, for all intents and purposes, doesn't exist and we can derive no useful value from, e.g. the result of division by zero. "Not defined" does not mean that there is an answer and we just don't know / can't agree what it is.

Phew! Maths lesson over (for now ). Anyone with high school kids, feel free to refer this discussion on. And yes, I used to be a high school maths tutor.

For anyone who was absolutely bored out of their minds, just remember that when there's discussion about anatomy on this board (there are many doctors!), even though I know that is more applicable to us, I still have not much idea what you're talking about most of the time