Skip to content

Backtesting trade systems

6 messages · Robert Sams, Mark Breman, Jeff Ryan +2 more

#
Hi Mark,
 
I have started a package called tradesys which, I think, is a clean
solution. The project is registered on r-forge
https://r-forge.r-project.org/projects/tradesys/ and the initial code
base with documentation will be checked-in by the end of the day London
time. As a taster:
Open   High    Low  Close     Volume
2009-05-12 910.52 915.57 896.46 908.35 6871750400
2009-05-13 905.40 905.40 882.80 883.92 7091820000
2009-05-14 884.24 898.36 882.52 893.07 6134870000
2009-05-15 892.76 896.97 878.94 882.88 5439720000
2009-05-18 886.07 910.00 886.07 909.71 5702150000
2009-05-19 909.67 916.39 905.22 908.13 6616270000
<= MA(Close, 120))
phase      etime      xtime time nobs  eprice  xprice    pnl
ror
107    EL 2006-09-21 2007-09-12  356  244 1324.89 1471.10 146.21
0.264117052
108    ES 2007-09-12 2007-11-09   58   42 1471.10 1467.59   3.51
0.006027153
109    EL 2007-11-09 2008-01-03   55   36 1467.59 1447.55 -20.04
-0.034689959
110    ES 2008-01-03 2008-06-10  159  109 1447.55 1358.98  88.57
0.159301490
111    EL 2008-06-10 2008-07-21   41   28 1358.98 1261.82 -97.16
-0.187159273
112    ES 2008-07-21 2009-05-19  302  209 1261.82  909.67 352.15
0.825619186
trade states    delta    price          ror   equity
2009-05-12   112     -1 1.331220 6.814016  0.018107970 38.02601
2009-05-13   112     -1 1.307543 6.808377  0.007373275 38.30638
2009-05-14   112     -1 1.297973 6.784729  0.030694874 39.48219
2009-05-15   112     -1 1.259318 6.794318 -0.012075942 39.00541
2009-05-18   112     -1 1.274712 6.786796  0.009588169 39.37940
2009-05-19   112     -1 1.262606 6.813082 -0.033188777 38.07244
 
Please checkout and play with the code at your leisure. Anyone
interested in write-access to the repository should contact me directly.


Robert 


________________________________

	From: r-sig-finance-bounces at stat.math.ethz.ch
[mailto:r-sig-finance-bounces at stat.math.ethz.ch] On Behalf Of Mark
Breman
	Sent: 16 July 2009 15:15
	To: r-sig-finance at stat.math.ethz.ch
	Subject: [R-SIG-Finance] Backtesting trade systems
	
	
	Hello, 

	I have spend quit some time now looking for a package that
allows me to backtest (technical) trading systems based on single
financial instruments with R.

	I had a look at Rmetrics, blotter, fTrading,
PerformanceAnalytics, backtest, quantmod, TTR etc, but not one of these
fill my requirements. It's not that they are not usefull, on the
contrary, they are all filled with terrific statistical stuff, but it's
not the simple, practical and straightforward approach that I am looking
for as a trader rather than as a statisticus.

	So I have decided to build my own solution, reusing as much as
possible from these existing packages. (As a former software engineer I
know how much time and effort goes into buiding reliable software, so
the more reuse the better). As I am quite new to R and statistics in
general, there is a lot to learn for me here...
	
	
	What I have build so far is a very basic set of functions called
"tradesim.R" (I have attached it to this post). A very basic example of
how these functions can be used for a backtest-run can be found in
"tradesim_example.R". The example runs a backtest with end-of-day data
from AAPL, using a (rather poor) trading system based on the RSI
indicator (from the TTR package). 

	Now I have read in some older post on this list that others were
also searching for a backtesting package. I even read a post proposing
to start a group effort creating such a package. I suspect that some of
you might be interested in what I made so far and maybe would like to
put in a effort creating such a package together. I certainly know that
it's a lot easier to create good software as a group, rather than by a
single person...

	So if you are interested have a look at what I got so far and
let me know what you think.

	Regards,

	-Mark-
#
All,

I suspect this topic/conversation is central to most of us -- and
quite important to R and R-Finance in general.

There are two primary issues that we seem to be encountering at this
point in the R-Finance community:

1) consistency of design: so all of our work becomes additive.
2) generality: writing code that works in the most general case possible

The first is quite difficult.  I have personally been involved in
*hundreds* of hours of productive (?) conversation with dozens of
people on this topic, be it on the list, useR, NY, Meielisalp,
R/Finance Chicago and back again at Meielisalp (and many sessions
involving Jak's tap in Chicago).  All of the conversations have been
certainly valuable, though even after all of this I still can't figure
out the best path...

One thing that I have worked on personally is making consistency
possible.  'xts' was born of this issue.  We didn't need another
time-series class.  We had 9 or 10.  We needed (or I needed) a way to
abstract the class and just get the job done.  'xts' does that
reasonably well -- though still far from complete.  The same issue
exists for portfolio level data, as well numerous other 'classes'.

Everyone should be free to use their own data object, what would be
nice (and required for maximum usefulness in my opinion) is if that
choice wasn't imposed on the end-user to use your software.  This
leads to more users, more feedback, better code, and a more 'complete'
landscape of tools that can be used.

As a time series example -- xts lets the developer use one type of
object (simplifying code), and accept *ALL* objects (simplifying the
user experience).

The point of the above is that interface counts, and it counts for a
lot.  If a framework is to work, it needs to be accessible to all
users.

The second point I'll toss out there is one of generality.

This is just as difficult as the first conceptually, though I would
argue possibly even more intractable.  We just can't individually
understand what we collectively require.

quantmod set about in 2007 trying to create a 'framework' and has
failed miserably.  It does some things like data management and
charting quite well, but the often asked question is how does
specifyModel/buildModel/tradeModel work.  The short answer is that it
does, and it doesn't.  It works on one type of strategy (EOD), and
doesn't on others:
loading required package: rpart
Model:  rpart1247761259.05370

  C.A.G.R.:  16.96%     H.P.R.:  67.94%

  Returns by period summary:

            weekly monthly quarterly yearly
    Max.    12.29%  18.96%    21.12% 52.23%
    3rd Qu.  2.43%   7.51%     8.84% 28.51%
    Mean     0.49%   2.10%     5.46% 20.50%
    Median   0.47%   0.78%     4.58%  4.80%
    2rd Qu. -1.63%  -3.01%     0.80%  4.63%
    Min.    -8.89% -10.71%    -4.87%  4.46%

  Period to date returns:

             weekly monthly quarterly yearly
             -0.44%   0.75%     0.75%  4.46%
Model:  rpart1247761259.05370

  C.A.G.R.:  29.76%     H.P.R.:  136.82%

  Returns by period summary:

             weekly monthly quarterly  yearly
    Max.     25.22%  36.09%    36.23% 105.40%
    3rd Qu.   4.72%  14.80%    17.59%  56.63%
    Mean      0.97%   4.05%     9.56%  39.50%
    Median    0.87%   1.46%     7.90%   7.90%
    2rd Qu.  -3.38%  -6.20%     1.34%   6.57%
    Min.    -17.15% -20.97%   -10.30%   5.24%

  Period to date returns:

             weekly monthly quarterly yearly
             -0.95%   1.35%     1.35%  5.24%
Looks great!  But it is useless.  It is a casualty of specificity.  A
generalized framework would be awesome, but I think it is a much
larger task than I can handle.  I suspect that general to one person
is fantastically restrictive to another.

R is the 'general' framework.

What we really need is consistency of the pieces that make
building/testing models in *R* easier.

This comes from projects like blotter I think.  Were we can use parts
that we want, and only those that we want.

As I said at the start, this is a lot more involved than it looks
like.  Obviously best of luck to all who take up the challenge.  This
thread is an awesome start to the (larger) public conversation that
has been taking place over beers for quite some time now.

Best,
Jeff
On Thu, Jul 16, 2009 at 9:41 AM, Robert Sams<robert at sanctumfi.com> wrote:

  
    
#
Robert,

In the "details" section of your RollingFunctions documentation, you
note that you want to add "LAG, TR, ATR, EWMA, etc."  All of these
functions, and more, are already in TTR.

TTR uses xts internally, which provides support all major time-series
classes, not just zoo/xts.  Additionally, many of TTR's functions are
very fast because they use compiled code.

Best,
Josh
--
http://www.fosstrading.com
On Thu, Jul 16, 2009 at 9:41 AM, Robert Sams<robert at sanctumfi.com> wrote:
#
I'll add to Jeff's comments a little, but I think he's absolutely right
about working towards integration of various components.

PerformanceAnalytics has always been intended for statistical evaluation
of the resulting returns generated by trading systems, and has been
carefully scoped that way.  Although we started writing it before zoo or
xts came along, we had long wished for a time series package such that we
could concentrate on the objectives of the package rather worry about
underlying mechanics.  For me, zoo and xts are key components not only
because they make development easier, but because they should also make
integration easier.  That's why we're continuing to work to  move away
from our own (legacy?) code and take advantage of all that xts offers.

Blotter is another example of a component.  blotter takes it's name from
the "trade blotter," which is used by traders for recording transactions. 
blotter is *not* about creating trading strategies, but only about
managing trades, positions, and calculating p&l on those trades/positions.
 We will be extending it shortly to handle multiple instrument types and
currencies, as our requirements are for worldwide markets and multiple
different asset classes.  So, in that paradigm, the "trading system" would
generate a list of trades, and 'blotter' would be an interface for
evaluating performance, keeping records, etc., completely agnostic of the
process that generates trades.

Although blotter is still immature code, it's pretty functional already
given that it benefits so much from the existence of xts.  To see how to
use blotter, install it from r-forge and take a look at:
library(blotter)
example(blotter)
demo(turtles)

The example is a relatively simple one with a few trades in a few stocks. 
The demo is a more developed example of a trading system.  In this case,
it's a trend following system originally developed by Josh Ulrich that
uses signals from TTR, charts and prices from quantmod, and blotter to
calculate P&L.  There's a lot to do still, but I think it hints at the
possibilities here.

pcc