I have been
analyzing my investment process and am realizing that the weakest link
continues to be the various biases which commonly impact us. If I look back at
the last 15 years of my investing life, I can safely say that I was fluent in
the basics in the first couple of years and could identify good ideas by the
fifth year.
The above
statement would imply that I was an expert by year 5 and poised to be a good
investor. Unfortunately the reality was far from that – you can read my journey
till 2008 here.
Knowing what to do is different from doing it.
Let me list a
few biases and how I was impacted by them. I will also try to explore what one
can do to avoid them
Social proof
This is a
bias where in one is influenced by other investors and the general mood of the
crowd. I wrote about a mistake
I committed a long time ago – purchase of SSI and IT mutual funds during
the dot com boom.
Although I
was new to investing (around 3-4 years), I understood the importance of
valuation and of not overpaying for stocks. Inspite of being cautious for the majority
of my portfolio, I still went ahead and committed 25% of it to IT related
stocks. As I look back, I recall that the main reason was that a few of my
friends were investing heavily in this sector (and getting rich). In addition
to this, a nice and pretty broker also recommended a few hot mutual funds (such
as ICICI technology fund) which were sure to make me rich in a few years.
How could I miss?
I managed to
lose 80% of my capital in a short period of six months. This was unmistakable
evidence that I had made a spectacularly wrong decision. Ever since then, I
have followed a few simple rules to avoid getting influenced by the crowd- Do not buy hot stocks. If the media is talking a lot about some hot sector or all my friends are getting into it, I will just avoid it. As a result I did not touch the real estate and infrastructure stocks during the 2007-2008 period and spared myself of a lot of agony
- Do not take stock tips from anyone, especially pretty girls J
Anchoring bias
This is a bias wherein one gets fixated on a variable in the decision making process and uses that to make all subsequent decision. This is a difficult bias to recognize and overcome.
I had been following Crompton greaves limited for some time and decided to buy the stock in 2011 after the company reported poor results in the first quarter. The stock dropped quite a bit after that and I started purchasing the stock as it ‘appeared’ cheaper compared to the past results.
In the case of stocks, investor returns are dependent on future performance, but the data to evaluate that comes from past performance. It is an art, more than science, to evaluate the past results and arrive at an appropriate conclusion. In the case of Crompton, I got anchored to the price and the past fundamentals and did not weigh the state of the industry and management issues more heavily.
How should one avoid this bias? Once you have purchased the stock, it is very difficult to avoid the anchor of the purchase price and past performance. The best approach I know of is to be aware of this bias and constantly question your reason for holding a stock.
This is a tendency to be consistent with one’s behavior in the past. It is a good way to behave in life – if you have been a decent and honest person once, you want to continue and be committed to that behavior.
However this
behavior can cause a lot of trouble for an investor. Once you have purchased a stock, there is a
tendency to be committed to it and as a result one tends to underweight any
negative information about the company.
Look at any
stock boards – majority of the investors are talking about the positives of the
company. If you are already invested in the company, does it make sense to find
any additional information which just confirms your belief? How will that
benefit your decision?
I have
suffered from the same bias and I can’t think an easy way to avoid it. I have
purchased value traps like Cheviot
Company and held onto them even though the company continues to deliver mediocre
performance and the stock price was stagnant.
The approach
I take now is to rank all the companies in my portfolio in a descending order
of attractiveness. This forces me evaluate more idea more objectively. Once I
have my rank, I compare any new idea with the last idea in the list. If the new
idea is better than the last one on the list, it gets replaced.
The title of
this post comes from the concept of Darwinian selection – kill the weakest
ideas to make way for the stronger one. This also reduces the impact of the
commitment and consistent bias.
I plan to
cover additional biases such as the authority bias, availability bias and more
in the subsequent posts. ----------------
Stocks discussed in this post are for educational purpose only and not recommendations to buy or sell. Please contact a certified investment adviser for your investment decisions. Please read disclaimer towards the end of blog.
10 comments:
Can you name some of the books on behaviour finance that you are reading?
Hi Rohit,
Interesting thoughts. Just wanted to pick your brains on the new stock replacing the least attractive stock bit. Two part question one leading to the other.
1) For most people high attractiveness = high weight. Is it any different for you??
2) If high attractiveness = high weight for you, then how will you position size because as per what you have written any new idea will automatically have a small weight irrespective of how attractive it is??
Hi Rohit,
Love reading your blog posts.
In commitment and consistency bias you mentioned about how an investor may get too much positive information about a company from other investors and social platforms.
When you start analysing a company, wouldn't playing the role of a devils advocate sort of overcome this bias to a certain extent? You think of likely negatives and what could go wrong??
Regards,
Hi manish
a good book is thinking fast and slow. have been reading that book recently
rgds
rohit
Hi abhinav/nivrav
good to see you here.
To your question - yes an attractive idea has a higher weightage for me too.
However I have different approach in reaching full weightage. When I find a new idea, even if I am confident, I keep lower weight in the portfolio. Then over time as I get more comfortable and confident of the company, I keep adding to it. If the price remains attractive (which these days is quite common) and if the companies does well, then the weight increases and it goes up in the ranking.
downside is that if the price shoots up. in that case this approach fails. In some cases, if I really like the company, then the least attractive idea goes out, the new one comes in and I add extra capital to bring will weight. this is possible as I am rarely 100% invested
rgds
rohit
hi anon
that's true ..you can play devil's advocate to reduce this tendency. however in my experience it is not easy and not as effective.
the mind (atleast mine) works like a shutout mechanism ..once an idea gets it in, it takes me a long time to change my mind. I mean, the facts have to really hit me on the face to make me change my opinion
rgds
rohit
Good one Rohit.
Yes, it is very difficult to kick the sucker. I like your approach O
We definitely need to overcome this bias if we want to make big bucks :-) i.e. improve portfolio performance.
Thanks,
Vikas
Hi Rohit,
last part of the article about ranking the stocks in portfolio is fantastic idea...It is the such a simple yet powerful concept we always ignore..thanks for sharing :)
hi vikas
thanks for the comment. agree with you ...though difficult to execute
prasanna - that's true ..it helps in cleaning out the weak ideas. not easy, but still helps
rgds
rohit
Nice post Rohit, however I disagree on one point:
"The title of this post comes from the concept of Darwinian selection – kill the weakest ideas to make way for the stronger one."
IMHO, Darwinian selection does not imply survival of the strongest, it talks about survival of the fittest i.e. the one that best fits the sample path that transpired.
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