valuation of existing IR swap – example

Based on (downloaded to C:\0x\88_xz_ref)

On P54 the “closing a swap position” discussion is … very relevant. Start at the example on P57.

On T+0, enter 5.5%/Libor swap as fixed payer.

On T+1Y, prevailing (par) swap rate drops to 5%. Bad for the fixed payer as she has commitment to pay 5.5%. She wants out, and she doesn’t need any more loan. You can assume she has cancelled her project altogether. So she would hedge out her floating exposure and realize any loss on the fixed leg.

Specifically, she enters a new swap as a fixed Receiver this time, receiving (the lower) 5%. The new floating leg perfectly cancels the existing floating leg, with identical payment dates.

As a result, for the next 4 semi-annual payments, she would receive 2.5% and pay 2.75% every time. This is the kind of loss she must accept when closing the swap in an unfavorable market. If you sum up the present value of these 4 negative cashflows, you see the (negative) present MV of the fixed position. (Note each swap deal has a $0 market value at inception.)

(The “fixed position” means the position of the fixed Payer.)

As of  T+1Y, the fixed position has a negative mark-to-market value given on P60, -$94,049 on a $10m notional.

It follows that to the original fixed Receiver, this existing swap deal now has a positive market value. Intuitively, this receiver is paying a below-market rate (5%/year) to receive the stream of floating coupons (i.e. the silver). The same stream is currently selling at 5.5%.

Yes it’s confusing! I feel the keys are
1) how to cancel out the floating leg exposure. You will then figure out that to close the swap, you need to take up a new fixed leg.
2) That would tell you the upcoming cashflows are positive or negative.
3) By summing up the PV of those cash flows you get the current MV.

Final MV formula is on P70.


##HFT: some defining features relative to similar systems

I learned from a seminar. I didn’t do any research. Just some personal observations.

  • HFT is different from a broker execution algo in terms of holding period. HFT never holds a position overnight.
  • HFT is alpha-driven. In contrast, a strictly sell-side trading engine is driven by customer flow.
    • however, HFT doesn’t use market orders as much as limit orders, so it may appear to be market-making.
  • an HFT engine makes many, many trades in a day, but so does an execution algo.
  • HFT usually makes no directional bet. In contrast, fundamental strategies have a view. I know many sell-side traders have a view and may hold inventory overnight.

I think the distinction can become unclear between HFT and execution algos.

slippage: several similar meanings

slippage = difference between 2 prices — the earlier quoted by an OTC dealer (FX, bond, swap…) vs the requote when you take that quote. In many quote-driven markets, all public quotes are always indicative.

slippage = difference between 2 prices – the EOD benchmark vwap vs your block order’s execution vwap, assuming order filled within a day.

If order is to be executed from 2pm to 4pm, then the benchmark vwap should be calculated accordingly.

slippage = difference between 2 prices – the price that triggered your trading signal vs execution price. see

your compiler ^ the c++ standard

C++ has many compilers offering extensions.

Many developers write code based on the c++ standard. You could decide “if this operation fails, I would get this particular error according to the standard.”

Well, unless you are aiming for portability, you had better respect your local compiler more than the language standard. Your local compiler could add a “feature” and avoid raising that error. Side effect – you don't get “reminded” and you assume everything worked as expected – dangerous. There could be a compile-time warning but then it's often drowned in the noise. Poor signal/noise ratio.

My stance — know your compiler. Whenever the standard says some unusual condition should end in a certain way (or one of several ways), check your compiler's conformance.

It's also possible that the standard says this condition should return a null pointer or silently return, but a compiler adds a much-needed diagnostic feature to catch it. Sounds too good, but then the problem is, if you tweak some debug-build settings (or when you port your code to another compiler) you could lose the “reminders” that you depend on. Your code may appear to work in UAT but fail in production.

the "stream" concept in c++/c#/java

C had ascii/binary read/write functions. C++ introduced a family of “stream” classes as a complete replacement.

java and c# embraced and expanded the stream concepts and kissed goodby to the C legacy. I guess stream must be an immensely successful invention. Before we look at all the new stream classes like MemoryStream, GzipStream, StringStream… it’s good to understand the fundamental innovation. See

I feel streams have become more versatile over the decades. Initially IO constructs for file and socket only. Then IPC. Then serialization. Then …

I particularly like the ostringstream — the “string builder” in c++.

Can we say the producer-consumer pattern is also stream-based? Probably not. Streams usually hold bytes or characters, not commands/tasks.

VWAP market impact =? slippage

Suppose we have a 5000 IBM buy-order. VWAP is the benchmark chosen. Our goal is to predicted market impact. If the predicted MI is too large, then we should either be very careful, or decline the block order.

The predicted market impact is also the predicted slippage.

Let's put in some fake but concrete numbers. Suppose we estimate that submitting this block buy would raise today's eod_vwap by 100 bps. That means whatever today's eod_vwap happens to be, our execution_vwap will be higher by 1%.

If eod_vwap is $70 then our market impact is about $0.70

If eod_vwap is $75 then our market impact is about $0.75

I think we should inform our client that we can execute the block order at the benchmark eod_vwap + some spread. I would quote a spread like $1 given spot is $69 and I estimate today's eod_vwap to be $69.50.

Suppose client accepts and we execute the order and execution_vwap = $69.9. What's the realized market impact? We can only imagine “what if I had not done this big order”. However, we can observe the benchmark eod_vwap = $69.10. We performed better than quoted. Slippage = execution_vwap – eod_vwap, so our slippage is smaller than our quote!

100-gunmen puzzle

Problem — Suppose 100 gunmen stand in a big circle arranged by height, clockwise from #1 (lowest) to #100 (highest). In first shooting round, #1 starts off by shooting clockwise, so #2 gone. Then #3 shoots clockwise at #4, and so on. First round ends, and the lowest among the remaining gunmen continues to shoot clockwise. How many rounds will there be and who will be the last standing?
Assume each gunmen stays in his spot, and his spot has his name.
Analysis —
Let me first clarify the terminology.
* Each round has a “starter” shooter. The round ends immediately before he shoots again or immediately before he gets shot.
* Each round has a InitialCount being the number of gunmen immediately before that round.
Solution —
Round 1: starter is #1. InitialCount=100. This is an even round, so the starter remains.
Round 2: starter is #1. InitialCount=50. This is an even round, so the starter remains.
End of Round 2 the remaining shooters are #1 #5 #9… #97. They are 4 (i.e. 2^2) stops apart.
Round 3: starter is #1. InitialCount = 25. This is an odd round, so starter will shift anticlockwise by 2^2 to #97. Why am I so sure? Since InitialCount is odd, the highest (among the 25) gunmen will NOT die and will become the next round’s starter.
End of Round 3 the remaining gunmen are 8 (i.e. 2^3) stops apart. Therefore, highest two are #89 #97.
Round 4: starter is #97. InitialCount = 13. This is an odd round, so starter will shift anticlockwise by 2^3 to #89.
End of Round 4, the starter (#97) is a “sitting duck” to be shot soon.
Round 5: starter is #89. InitialCount = 7. This is an odd round, so starter will shift anticlockwise by 2^4 to #73.
End of Round 5, #89 is a “sitting duck” to be shot soon.
Round 6: starter is #73. InitialCount = 4, which is a power of 2, so #73 will remain the starter for all subsequent rounds and therefore the last standing.

For YuJia – trade at market close

My strategy assuems we could buy or sell at exactly the daily close price. There’s no bid/ask to worry about.

Although a stock market may close at 4:00 PM, many stocks continue to trade for at least 20 minutes after the close. We wait for the actual close price, and make our trading decision. There are risks to this practice.

* Trading volume typically plummets when the market closes. This causes market orders to become very risky. Therefore we use limit orders.

* Limit orders may not get filled, therefore we use total daily volume to throttle our trade size.