You are what’s on your Amazon Wishlist

Ξ May 28th, 2009 | → 0 Comments | ∇ Coding |

You are what’s on your Amazon Wishlist?

Just mucking about with a little regular-expression stuff – interestingly [frighteningly!], it adds up to £908.66

Subtle Logos – The Return!

Ξ May 15th, 2009 | → 1 Comments | ∇ Mumble |

I’ve just noticed what I believe to be a subtle logo that’s been going right over my head for quite sometime.

I’ve noticed things like this before with Amazon and Superman/Carrefour, but I believe I should have ‘got’ this one somewhat earlier!

I think the i> bit is meant to look like a play button – yes [or am I wrong]?

P.S. Yet another one.  This is the logo for Errington-Smith estate agents.  Took me ages to see it as an ‘e’ in an ‘s’!

Deltas Only Please!

Ξ May 15th, 2009 | → 0 Comments | ∇ Coding, Give me Strength, Microsoft, Mumble, Programming |

This stuff makes me wonder!

I can’t believe that for SP1 [Office 2007] that there are 322Mb of actual code changes – I mean the complete bloody product is only [only!] 532Mb to begin with!  [BTW, despite what the text says regarding Ultimate Extras, the chosen updates were *just* the Office 2007 SP1 updates]

So what we’re getting here is component updates as opposed to, for want of a better term,  code updates – it goes like this:

• Microsoft fixes a bug with a code change.
• The code is recompiled – the result being, of course, that the entire component changes [of which the fix is a tiny part].
• The entire component is then wrapped-up in a Microsoft update, and then the update is downloaded and installed by the consumer.

What *should* happen is:

• Microsoft fixes a bug with a code change.
• The code is recompiled – the result being, of course, that the entire component changes [of which the fix is a tiny part].
• The difference between the now out-of-date component and the ‘new’ is determined – this is called ‘a delta’.
• The delta is then wrapped-up in a Microsoft update, and then the update is downloaded and installed by the consumer.  The update is of course a little ‘smarter’ now – as the installer has to ‘patch’ the old component with just the changes – rather than replacing the complete thing.

Now I *know* that Microsoft can do this sort of thing, so why don’t they?  I’d certainly like to know how much extra energy and bandwidth would be saved if they did it the right way!

Not Much Use – IMHO!

Ξ May 14th, 2009 | → 1 Comments | ∇ Geeky |

I’ve been doing a little free web-development for some pals of mine, and, in the course of that, trying to get their website towards the top of all search-engine’s results.

So I was interested when a few days ago they had a call from a company that claimed that given a few keywords, they could guarantee to get them at the top of Google’s search results.

Hmmm, interesting!

When I told my pals that I doubted the credibility of such a claim [I got starry-eyed stares when I tried to explain to them the why of this], I thought I’d best have a look at what this company was offering.

In a nutshell, this company has got a Google AdWords account, and in using it, they will, for a few pounds, place you at the top of a Google search – you know, in those ‘Sponsored Link’ bits.

Ok, so what’s the problem with that?

1.

Well they’re charging £20 per month – which is just enough to have most people say ‘well it’s not that much’ [and sign-up], yet either over or under what placing a top-result will actually cost you.

If you don’t know, Google ads ‘pay’ [Google] and ‘cost’ [you] whenever someone clicks them.  How much?   It depends upon a figure that you’ll have to agree with Google [it depends upon other bidders], and that fits within your budget – so here we’re talking about £20 per month apparently.

So what if you spend all your budget?  Well, you disappear from the results … rather, you slide to the place where Google’s PageRank algorithm would normally place you [which may be nowhere of course!]

So this company hopes that to place you will cost maybe a penny per click, and that for your 20 quid they’ll have some left over at the end of the month to pocket for themselves [that’s 2,000 people clicking through - so they probably will!].  But what if you go ‘over budget’?   Well, I assume they’ll either get you to stump up a bit more, or simply hope that you don’t notice your sudden disappearing act!

2.

Who clicks ads?

Well, there must be a lot of people that do, because that’s Google main source of revenue I believe!

Personally however, I rarely click them – for one thing, they’re mostly sat off to the right-hand side of the search results, so I don’t see them [I assume that the best payers are the ones that appear at the top of the search results – rather than towards the right-hand side].

But the main reason I don’t click them is because Google’s PageRank works very well, i.e., websites that rank highly via PageRank are normally worth looking at – as they’re effectively being voted for by others that link to them [see the link I just used above - well, according to Google, I've just voted for the webpage that explains PageRank].   However, is that true when someone pays to get themselves at the top of the results?  Probably not!  After all, if they were actually first-rate – worth looking at – wouldn’t they get there by themselves – through their own merit, osmosis – call it what you will? I think so.

The result is that the more savvy person will often not rate/trust a paid-for link – or at least not as much as one that makes it to the top through its own merit.

3.

Who will see the advert/link?

Well, maybe lots of people/maybe no one:

You’ll see it if:

1. the paying customer’s monthly budget hasn’t been used up when you conduct your search;
2. IF – and only if – you use Google!

Yup – no one will see it it they don’t use Google – perhaps they use Yahoo, or some other search-engine [Ask.com, A9.com, Live.com, …] – no-Google = no-Where to be seen.

More Probability – HTH vs. HTT

Ξ May 8th, 2009 | → 3 Comments | ∇ Maths, Oxford |

Imagine tossing a fair coin successively, and waiting until the first time a particular pattern appears; say HTT. For example, if the sequence of tosses was HHTHHTHHTTHHTTTHTH, the pattern HTT would first appear after the 10th toss.

Ok, now let’s take two such patterns – HTT and HTH.  Given both these sequences, and a lot of trials [where you conduct this, "it first appears when" experiment, and then average the number of tosses], is it more likely that you’ll:

• hit HTT in less tosses than HTH;
• hit HTH in less tosses than HTT;
• find that the number of tosses is the same?

Most people [many mathematicians amongst them] will pick the third option.  Surely, any such pattern is equally likely to show up in some yet to be discovered average number of tosses!

Actually, it’s not the case – that they’re equally likely. In reality the average number of tosses required to see HTH is 10, whilst for HTT it’s 8! How can that be???

Let’s see why.

Note that HTH overlaps itself, i.e., if you got HTHTH you’ll find that you’ve got two occurrences of the pattern in only five tosses, i.e., HTHTH and HTHTH. Ah, so doesn’t this sound like HTH is more likely then, rather than the other way around?

Well, with HTT there isn’t such an overlap – and it turns out – perhaps unintuitively – that that’s important; in a way that leads to HTH‘s downfall. So, let’s run a couple of experiments to see how this works.

Let’s go looking for HTH

Best scenario:

Toss	Result	Comment
H	1st token in our pattern	excellent start!
T	2nd token	quite excited!
H	3rd token	We won!

Second best scenario:

Toss	Result	Comment
H	1st token in our pattern	excellent start!
T	2nd token	quite excited!
T		Bugger! Now we’ll need to continue tossing the coin until we see an H; as that’s the first token in our sought-after sequenc

Now let’s go looking for HTT

Best scenario:

Toss	Result	Comment
H	1st token in our pattern	excellent start!
T	2nd token	quite excited!
T	3rd token	We won!

Second best scenario:

Toss	Result	Comment
H	1st token in our pattern	excellent start!
T	2nd token	quite excited!
H/H		Bugger! However, and this is the important bit, at this stage we don’t need to toss the coin again in order to get to find our starting token – we just threw it – an H!

If you doubt any of this, here’s a little simulator I wrote [CoinToss.zip contains CoinToss.exe].

21 – Blackjack Movie

Ξ May 6th, 2009 | → 1 Comments | ∇ Books, Geeky, Maths, Oxford |

Watched 21 last night – not a bad film, in fact, regarding entertainment vs. cost value [it ran us just £3 from Matalan!] it was rather good.

The film is based upon the MIT Blackjack team, and as I’ve read/and-seen quite a lot about them before, I was quite happy to have the film thicken the plot [maybe that should be 'have one'?] – and there’s a nice twist or two at the end.  As to the film’s inspiration, you can’t do much better than watch the BBC Horizon documentary on this:

Making Millions the Easy Way

• Part 1
• Part 2
• Part 3
• Part 4
• Part 5

I wish ‘Oxford types’ would get up to stuff like this [of course, they might do (would they tell their lecturers?)]; it’d be so much more fun!

Probability

I was quite pleased to see some probability stuff in the film being partially explained, i.e., their running through the Monty Hall problem [although the implied cleverness of the student here is a bit hard to swallow really].

Anyway, here’s the problem:

Suppose you’re on a game show, and you’re given the choice of three doors:  Behind one door is a car; behind the other two, goats.  You pick a door, say number 1, and the host, who knows what’s behind all of the doors, always opens another door – to reveal a goat – let’s say that’s door number 3.  He then says to you, “Do you want to swap?”, i.e., swap your initial choice of door number 1, and change to door number 2?   The crux being – is it to your advantage to swap?

In the film, the problem is presented in this clip.  By the way, the answer is in this too, so if you want to think about it, get ready to hit the pause button at the 44s mark!

The explanation I find that works quite well here [and I've had my Oxford stats students scratching their heads over this problem initially (as do most people I believe)] is:

Given this scenario: when you pick a door, you’re more likely to pick a goat-door than sole car-door, i.e., you’ve a probability of .66 [or 66% chance if you prefer] of picking one of the two goat-doors vs. the only car-door.  Hopefully, that’s obvious.

So, if chance [substitute luck of the draw/fate/the odds/divine-intervention ...] did the right thing here, and you picked a goat-door, you know with a decent probability that the car is behind one of the two remaining doors – but which one?  Now, when the host reveals another goat behind one of the two remaining doors, the car’s obviously [again, if the odds etc worked for your initial pick] behind the other door!

Basically, it comes down to this: if you picked a goat-door initially [which you will 66% of the time], by swapping later, you’ll always win the car.  Conversely, and given once again that you initially picked a goat-door, if you don’t swap, you’ll lose 66% of the time.  Or, one other way … by swapping, you’ll only lose if you picked the sole car-door as your first pick [which you're likely not to have done].

Update:  Just found a nice little simulator of this [Internet Explorer only] at http://www.grand-illusions.com/simulator/montysim.htm

The Times – Here’s a suggestion

Ξ May 3rd, 2009 | → 0 Comments | ∇ Mumble |

If you’re a Times reader, you’ll have no doubt played ‘Find the start/end of Times 2 [T2]‘!

So, here’s a suggestion – flip the T2 section over 180 degrees; so that its folded-edge is easily visible from the main paper’s cut-edge!  Simple, and easy to implement I reckon!

XBox 360 Networking/Internet Access Made Easy

Ξ May 3rd, 2009 | → 2 Comments | ∇ Geeky, Microsoft, Mumble, Rant |

I hate gaming/gamers!  Probably because A) I can’t see the point [read a book, go for a walk, ...], and B) because two people I [thought I] knew very well are very sadly addicts – one for The Sims [or practically anything else that might distract them from normality/life], and the other for the World of Warcraft [where she's a kiss-ass Elf, or some such shite!].  Oh, and C), my twelve-year-old son also plays too much!  Sad individuals indeed.  I truly can’t see the point.

Anyway, rant over, my son received a one month’s free trial on XBox [Saddoes] Live – or some such thing – and asked me if I could get his XBox 360 to connect to the Internet.  As he’s in a room where there’s no wired network point, this meant doing it via a wireless connection.

So, on checking out the various sockets on the back of the 360 box, I tried connecting the thing using a LinkSys USB wireless adapter I had laying around. It didn’t work, and upon further reading, I’m led to believe that one requires a special Microsoft adapter.

That’s the bad news.

Now for the good news … if you’ve a wireless laptop, that also has a wired network-interface, there’s a workaround:

1. Connect your laptop to the Internet, via its built-in wireless;

2. Connect your XBox to your laptop, via a standard network cable [one is supplied with an XBox 360];

3. Bridge the laptop’s wired and wireless connections.

So, here’s the steps I went through on my ThinkPad [with XP installed]:

1. Boot/connect the machine to the network, via its wireless;

2. Connect the XBox to the ThinkPad’s wired network interface using a standard network cable;

3. Open your laptop’s Network Connections [Start | Control Panel | Network Connections];

4. Select both the wireless and wired connections;

5. Right-click on the selected connections, and select Bridge

Here’s the result:

And that was it:  son-networked, playing even more games … hmmmmm – did I do the right thing?

Wolfram Alpha

Ξ May 3rd, 2009 | → 0 Comments | ∇ Research, Science, Technology |

Wolfram Alpha seems like a funky thing – not a “search engine,” but a “computational knowledge engine” [Wolfram's words]. Apparently it’s implemented in 5 million lines of Mathematica code.

Here’s a Slashdot mention with more links.  And, here’s a video of a public demo.  Pretty poor quality, but it does at least show it in action.

Lastly, here’s a link to a time-lapse video of the hosting datacentre being built.