An Absent Serpent

[izmeina]

Just a quick squiggle to say that the serpent is in snooze mode a lot lately. The weekend at Petunia's place is read only when it comes to surfing in Cyberia due to a keyboard with a few malfunctioning keys.
Been lots of juicy tasty posts from serpent associates but most unlikely to be able to reply until Wednesday

Still got all those homework assignments to catch up on. It is sad to say that for a creature who loves learning all sorts of strange stuff and long may it be of no possible use at all, the Izzie has ended up 'gaming' the Coursera crypto homework. When you get four attempts at each week's homework then at a certain point you can improve your score just by looking at the feedback from previous attempts without understanding half the questions
Decided to have another go next time the course is on offer and with a bit of luck the penny will drop and all the crazy stuff will click and suddenly make sense.

Learned the hard way that downloading video lectures is the weakest link. So still trying to catch up due to having only one day a week with access to decent download speeds.

There's lots of juicy gossip at the Mad House. Putting on the serpent's Sybil hat, any day now the old toad will be initiating a new round of hostilities. Still not got around to posting about the latest craziness and cost cutting

Tuesday evening will be devoted to watching video lectures and doing some last minute assignments. Hopefully Wednesday evening will be devoted to a bit of squiggling and lots of comments on all those interesting posts

Comments

[catness]

Oh, I do the same thing, the elimination method works wonders (plus the preview version of the course which includes the same exercises ;) Also considering to re-take the course (maybe not right now, which is in November, but the next time) if I screw up the exam. So far keeping up with the top score, but same as for you, some questions are pure guessing, and some are solved through intuition only (e.g. variables are good, constants are bad), which I'm afraid is unreliable in the long term... and the Week 6 programming assignment looks positively scary! Though it felt the same about week 5, but after perusing the lectures and peeking around the forum it turned out to be ok. I even ventured into the Python land, and it was my 2nd program in Python ever, the 1st one being for another course where it was also too difficult to stray from the recommended libraries.

Anyway, my most important Coursera lesson comes from the gamification design framework - the step #5, "Don't forget the fun!" It's a great opportunity to expand your horizons and kick-start the brain engine, but it doesn't make sense to kill yourself for the grades - if any voluntary project is not fun (in a very broad meaning, of course), then perhaps it's a wrong thing to do...

Alice in Mathland

[izmeina]

No top scores for Izzie. Just one 7.5 after another. But not complaining since last night's previous attempt on the third set landed this lazy serpent a most sad and pathetic 2.93. But it is amazing what you can learn in eleven minutes ;)
It's a sort of perverted version of the Monty Hall door game.

Like you, intending to do the crypto course again some time later in the future after picking up some basic parseltongue. That is one thing to be said for these courses, the structure and external deadlines work wonders. Got no problem grasping the concepts, it's deciphering all that mathematical mumbo jumbo that is the killer. But was pleased one week to look at a few lines with all those m's and n's and realized that mathematical symbols were saying that the code breaker had to come up with a new valid message that was not one of the many already tossed their way in the adversary challenge.

The mathematical thinking course is fascinating. Silly Izzie really did this stuff in the wrong order. Maybe one day the Izzie really will be able to read "Godel, Escher, Bach" from beginning to end without skipping all the set theory bits.
And the mathematical thinking mob give you only one chance to do the problem sets so no chances to learn all sorts of interesting things about the laws of probability :(

But there's an unbelievable number of very anal and serious people out there.
What seemed a simple and straightforward set of questions got turned into life, the universe and everything and one huge troll fest. Sort of like the Monty Hall drama on steroids. Many of these box tickers were demanding the following two questions be reformulated because they picked F and it ruined their otherwise perfect score on the test that can only be submitted once.

So here is the sad tale of Alice

Which of (a)-(e) is most likely? Or does (f) hold?
(a) Alice is a rock star and works in a bank
(b) Alice is quiet and works in a bank.
(c) Alice is quiet and reserved and works in a bank.
(d) Alice is honest and works in a bank.
(e) Alice works in a bank.
(f) There is no definite answer.

Which of (a)-(e) is most likely? Or does (f) hold?
(a) Alice is a rock star or she works in a bank
(b) Alice is quiet and works in a bank.
(c) Alice is a rock star.
(d) Alice is honest and works in a bank.
(e) Alice works in a bank.
(f) There is no definite answer.

Pages and pages of folks insisted that the answer in both cases had to be f because 'We haven't been told anything about Alice'
Izzie looks and thinks "This is not about Alice, it's all about 'and' and 'or'

It was amazing and amusing to read these discussions like a bunch of medieval monks discussing how many angels can dance on the head of a pin. They had truth tables, the rack and all sorts of infernal devices at hand to justify their claims. Who would ever think that logic could be such fun?

Re: Alice in Mathland

[catness]

So this course could be fun! I was discouraged by "mathematical" in the title ;) Maybe I should take it some other time, now I'm overcommitted - 2 courses are about to end, but I signed up for 2 more - Compilers, and Interactive Programming in Python. So much exciting stuff. Did you know there's a course teaching how to write songs, and a course teaching how to play guitar? These are a few months from now though. Also got an email about online Stanford courses at another site, including a course on creativity: http://venturelab.stanford.edu/creativity But this one requires teamwork and a lot of commitment, so I doubt it's a good idea.

I'd say it's e) for the 1st question, and a) for the 2nd. Just basic probability math, the answer f) would be applicable if there were 2 or more choices with the same highest probability (e.g. if the 1st question didn't include e) as an answer).

I think retaking quizzes is a way of learning from your mistakes. I'm sure that prof. Boneh, being a security expert, is aware of all the possibilities of "gaming the system" in such a primitive way, and if it doesn't bother him, it means he's fine with it. There are courses which are even more generous - in Model Thinking, there are 5 attempts, neither questions nor answers are changed, and the review provides most detailed explanations, formulas and all, together with the actual answers even where you have to type the values in. Believe it or not, some people complain about that too, because they feel that the quizzes are too easy and it will devalue their certificate ;) (The common answer is "do not retake the quiz if you feel it's cheating" ;)

Good luck!

Re: Alice in Mathland

[izmeina]

Izzie picked the same as you also. Had no idea there was such a fuss. Stuffed up a whole bunch of questions with truth tables. It was Tuesday evening and the relevant video was taking an eternity to download and then stopped right at the spot where all the new territory was. So had to do the quiz in the dark using common sense and muggle logic without mathematical symbols. Was so happy to find such a simple and straightforward set of questions especially at three marks each (in a total of 21)

It was only later coming across all the 'We need to talk about Alice' posts that this serpent became aware of the drama
But can you believe that Izzie made a special trip to this net cafe in the city in order to print out the five assignments that don't count towards the final grade! Like nano plotting and planning, this is the sort of stuff best saved for a cafe using old fashioned pen and paper and not done during very precious online time in the evening

Not peeked at the video yet but the Izzie just loves evil fictional dystopias

Re: Alice in Mathland

[izmeina]

Izzie also got that link in the email. Got quite excited until reading the small print. Vidoes, teamwork, cooperation. No thanks. Will stick to our good old fashioned tarot decks and the wonderful advice of one D Hofstadter that creativity consists of finding connections between apparently unrelated concepts. Two at a time is a pretty good start.

The crypto quizzes - the ones where there's no little ticky boxes with all the answers but only your own choice and the commentary, they are very good for learning from mistakes. It was annoying the first time but rearranging the order of the answers and the odd change in answer options is very good for learning. The simple requirement of studying the form to pick the right ones next time may lead to the odd eureka moment

p.s. Dark future of gamification

[catness]

You gotta see this video! http://vimeo.com/46304267 (It was among the exam questions.) Even if you're not interested in games, you're interested in dystopias :) Actually, this technology would be awesome if it falls into the right hands. (Such as mine ;)