Hi, I passed the test, and am interviewing with the director tomorrow. Wish me luck!
The first test involves multiple step calculations and a bit of reading;
e.g. You have bought 100 options worth $25 each. They appreciate by 10% but then drop by $4. How much paper (means unrealized) profit/loss have you made?
There's also a brainteaser or two such like the angle between the hands of a clock or how long does it take for a task to be complete given varying levels of manpower. As I recall, it's something like 40 questions in 30 (or 25, I forget) minutes and you need 20 to pass, there are no penalties for skipping or mistakes.
The next test involves 26ish brainteasers in an hour. Questions would include spatial sequences, matchstick problems and even logical elimination (a given set of true/false related statements, you have to determine which is true).
I'd say the tests aren't that difficult but I have worked on my arithmetic quite a lot and have run through a Mensa puzzle book. In terms of preparation I would recommend doing a lot of practice. Hideous amounts. Multiplying/adding/subtracting/dividing the digits on the car number plate, your grocery shopping before checking out (if you like a challenge, try beat the till guy), phone numbers, stock prices or whatever that helps you practice. I think I may have developed an OCD but whatever gets the job done, really.
I highly recommend that you have a go at Brain Training Academy on the DS, scoring at least 600g on the calculation test and practicing using this;
http://www.jimmyr.com/blog/speed_math.html
You need to get 10 stars on all Additions and Multiply: Basics . I used to do 200 of each daily. Although you won't be tested on say Multiply: Medium, it actually helps you build accuracy if you can do it in your head.
If you've got other companies, especially the Dutch ones, the tests are structured as such (google Optiver tests and trawl the forums);
Test 1: 80 questions in 8 minutes. The preparation as above should be sufficient. (Crucial - this is where 95% of candidates mess up. You don't get to the next phase if you don't pass)
Test 2: Sequences and series
Test 3: Multiple step calculations (similiar to Test 1, just longer)
They're also fonder of using fractions (i.e. 12/48 + 6/8 =?, ?*1/13 = 26/15) and that's very important, because if you're not used to it, you'll get thrown off. I haven't found decent training for this other than building your own.
The first test is the most important. If you can do the first, you often can manage the other two. The tests are negatively marked (+1 for each correct, -2 for each mistake or skip. It's a new standard, I'm told) and are multiple choice. There's an amazing amount of information about this floating around the internet so read around. You need a score of 53 to pass.
The sequences and series (numerical, not spatial) test is quite tricky but if you're very, very quick at the math, you should be able to figure it out. If you manage the first test, you can manage the third test as it uses the same skills.
Sorry for the monster post. Didn't actually intend to talk about the Dutch companies but there you go.
Good luck to you potential test takers.
