Investing in Women-led Fortune 1000 Companies
quantopian.com
quantopian.com
This is an effect that minorities face in general. They have to be the absolute best in order to break through the glass ceiling. There are plenty of male CEOs who are utterly mediocre, and mediocre women never get a shot at the CEO spot.
Or, years of fighting "the patriarchy" has left females uniquely qualified to lead companies in the fight against changing market conditions.
Or, prospective female executives are probably very aware of the social and political climate we live in and that may make them more risk averse in regards to accepting positions, they may place a higher value on taking positions at companies on the upswing.
We can do this all day but I doubt the data's going to give a clear answer, we'll all see what we want to.
A naive approach to this analysis is as follows. Take all the companies currently in the Fortune 1000, and look to see which of them has had a female CEO in the period under study. Backtest with buys and sells on the dates of hire/termination.
If this is indeed how it was done, the benchmark will almost assuredly underpeform simply because of the underperformance of components that are no longer in the index today.
After that, you may have to worry about dividends. I'm not sure if the platform takes them into account when you send buy sell order, but if it does, make sure you look at a portfolio that purchases SPY over that period, not merely the price, as the appreciation won't reflect the dividends paid.
Looking at the volatility is a good suggestion and definitely something to consider. I noticed the trend as well, but haven't dug into it yet.
The volatility thing it the biggest effect though.
Edit: Just saw that this is an interactive notebook! Awesome! Going through it now.
Edit2: It looks like you've already done what I planned to do! Awesome work!
I finally got the annualized sharpe calculation figured out. You can see what I did here: http://imgur.com/HlcjNYz but it shows my sharpe as 0.66 and the SPY as 0.3....
Honestly, this seems implausible to me...so I will keep digging. :-)
Regardless, stats like this hopefully help erode long standing views of women and leadership.
They said the opposite, that the culture of the company has to be a certain way to have a female CEO in a world of mostly male CEOs. They didn't say that a female CEO creates that culture, and that would have the chicken-egg problem (i.e. how does a CEO create a culture that within itself helped cause a CEO get into the role? They could continue it however).
PS - I should clarify that I don't agree with the OP's point about culture. I actually subscribe to the notion that becoming a female CEO is so difficult the only ones who manage it are just "that damn good" that their companies do better.
(This is why I follow patio11. Reading his tweets and HN comments is not unlike unpacking a particularly obtuse if-else-if statement block. Difficult, but rewarding!)
Point I want to make is, people are different starting from blood type, height, weight to "n" number of parameters and we can get different graphs for different parameters but that won't conclude anything.
Each person is different and just because some one belongs to a category does not make that person any extra attractive for any job.
In my personal opinion, this type of validation rather than competence,track record,experience is not beneficial to organization or society and completely shortsighted. So please stop these generalizations like "women are so and so", "men are so and so" ...etc. There are good and bad elements in every category.
The fraction of CEOs that are women is dramatically smaller than the fraction of the population that are women. There is no qualitative explanation as to why that should be true. So long as that remains true, it's worth looking into why it is true. The relative performance of the group is fair game for investigation.
I think there are plenty of qualitative explanations especially if look back a few decades (since most CEOs are in their 50s).
Women didn't obtain the name number of university degrees as men until recently. Women often step out of the workforce in order to care for family, etc, etc.
All of these would explain where there would be a smaller pool of qualified women to take a CEO role.
For a disclaimer, the portfolio was also more volatile than most benchmark indexes, so looking at the Sharpe ratio in both instances (mine and OP's) is important.
The second version of the algorithm factors in leverage and there it hovers around 1.
Right now I take it for what it is a quick mock up of some shallow data. But it seems compelling enough to take a deeper Nate Silver ( http://fivethirtyeight.com/ ) style deep dive.
From an investment perspective, I think the best thing to do next would be to make sure I have the right benchmark. Ideally they Fortune 1000 would be the best one to use, but I need the historical Fortune 1000 companies for the last 12 years….that will take some manual work to pull together.
At some point, though, the control group is an academic exercise. If the strategy makes money - invest.
I would be interested in a breakdown of other factors, but I expect very little variance actually derives solely from gender of ownership once you account for other conventional biasing factors of the chosen index.
[0]: http://performance.morningstar.com/funds/etf/total-returns.a... (Compare to S&P500 TR)
sample_size == population_size
Many other elements of the analysis can and are being challenged, which is fine to discuss, but there's no need to discuss "sampling" issues, as there is no sampling going on.