Oh God, I remember the fear as if it was yesterday...

This_Year

TopQuark wrote: »

Mass spectrometry. A very useful analytical technique!

I go to Specsavers

jellyhead

Johnmcl7 wrote: »

The Monty Hall Paradox is one of my favourite maths problems, the maths behind it is pretty simple but I like it as initially it just doesn't make sense.

Imagine a game show with three doors behind one of which is the prize and nothing behind the other two, you must choose a door in the hope of getting a prize. Before your door is opened, the game show host opens one of the other doors which is empty - it is always an empty door he opens as he knows what is behind each door. You now get the choice to stay with your original choice or switch to the other, still closed door. Should you switch to give yourself a better chance of winning the prize or should you stick with your original choice?

http://www.bbc.co.uk/news/magazine-24045598

John

That one hurts my head, although I like the idea of being greeted by a goat

In my tiny brain sticking or switching both have odds of 50/50 despite everyone telling me otherwise. The football analogy doesn't do it for me because a football game isn't just down to luck like the toss of a coin. A better team are more likely to win.

HeadAboveWater

I did Maths and Additonal Maths for GCSE and Maths for A-Level. The soh-cah-toa thing rings a bell but I have no notion what it is!! lol

But agree with this...

j.e.j. wrote: »

I remember it from school days but have never actually needed to know or apply this, in real life! :rotfl:

:rotfl:

For all the English I learned over the years at primary and secondary school, there is one (yip just one!!) thing that sticks in my head: alliteration is the repetition of a consonant or it's sound in a line of poetry! (but please don't ask me the english definition!!)

gunsandbanjos

Johnmcl7 wrote: »

The Monty Hall Paradox is one of my favourite maths problems, the maths behind it is pretty simple but I like it as initially it just doesn't make sense.

Imagine a game show with three doors behind one of which is the prize and nothing behind the other two, you must choose a door in the hope of getting a prize. Before your door is opened, the game show host opens one of the other doors which is empty - it is always an empty door he opens as he knows what is behind each door. You now get the choice to stay with your original choice or switch to the other, still closed door. Should you switch to give yourself a better chance of winning the prize or should you stick with your original choice?

http://www.bbc.co.uk/news/magazine-24045598

John

The Monty Hall paradox is fascinating, intuitively it sounds crazy but when you sit down and work out the odds it makes total sense!

Johnmcl7

jellyhead wrote: »

That one hurts my head, although I like the idea of being greeted by a goat

In my tiny brain sticking or switching both have odds of 50/50 despite everyone telling me otherwise. The football analogy doesn't do it for me because a football game isn't just down to luck like the toss of a coin. A better team are more likely to win.

When I saw this problem for the first time (before the days of ready access to the internet) I could not be convinced by my friend that it wasn't 50/50 to switch. What did eventually convince me was to work out each outcome and you see it's a two in three chance of winning if you switch. It's based on the probability of choosing the right door on the first go, if you always change then you will only lose if you chose the correct door on the first go which is a one in three chance. However if you always change, then you will win if you didn't choose the right door which is a two in three chance.

These are the possible choices and outcomes, in this example I'm assuming the prize is behind door 2:

I choose door 1, the host opens door 3, I stick, I lose
I choose door 1, the host opens door 3, I change to door 2, I win
I choose door 2, the host opens door 1, I stick, I win
I choose door 2, the host opens door 1, I change to door 3, I lose
I choose door 3, the host opens door 1, I stick, I lose
I choose door 3, the host opens door 1, I change to door 2, I win

John