Organizational Structure and Performance
The mathematical property of the optimal risky portfolio reveals a central feature of invest-
ment companies, namely, economies of scale. From the Sharpe measure of the optimized
portfolio shown in Table 27.1 , it is evident that performance as measured by the Sharpe
ratio and M -square grows monotonically with the squared information ratio of the active
portfolio (see Equation 8.22, Chapter 8, for a review), which in turn is the sum of the
squared information ratios of the covered securities (see Equation 8.24). Hence, a larger
force of security analysts is sure to improve performance, at least before adjustment for
cost. Moreover, a larger universe will also improve the diversification of the active port-
folio and mitigate the need to hold positions in the neutral passive portfolio, perhaps even
allowing a profitable short position in it. Additionally, a larger universe allows for an
increase in the size of the fund without the need to trade larger blocks of single securities.
Finally, as we will show in some detail in Section 27.5, increasing the universe of securi-
ties creates another diversification effect, that of forecasting errors by analysts.
The increases in the universe of the active portfolio in pursuit of better performance
naturally come at a cost, because security analysts of quality do not come cheap. However,
the other units of the organization can handle increased activity with little increase in cost.
All this suggests economies of scale for larger investment companies provided the organi-
zational structure is efficient.
Optimizing the risky portfolio entails a number of tasks of different nature in terms of
expertise and need for independence. As a result, the organizational chart of the portfolio
management outfit requires a degree of decentralization and proper controls. Figure 27.4
shows an organizational chart designed to achieve these goals. The figure is largely self-
explanatory and the structure is consistent with the theoretical considerations worked out
in previous chapters. It can go a long way in forging sound underpinnings to the daily work
of portfolio management. A few comments are in order, though.
The control units responsible for forecasting records and determining forecast adjust-
ments will directly affect the advancement and bonuses of security analysts and estimation
experts. This implies that these units must be independent and insulated from organiza-
tional pressures.
An important issue is the conflict between independence of security analysts’ opinions
and the need for cooperation and coordination in the use of resources and contacts with
corporate and government personnel. The relative size of the security analysis unit will
further complicate the solution to this conflict. In contrast, the macro forecast unit might
become too insulated from the security analysis unit. An effort to create an interface and
channels of communications between these units is warranted.
Finally, econometric techniques that are invaluable to the organization have seen a
quantum leap in sophistication in recent years, and this process seems still to be accelerat-
ing. It is critical to keep the units that deal with estimation updated and on top of the latest
developments.
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P A R T V I I
Applied Portfolio Management
27.3
The Black-Litterman Model
Product
Final Risky Portfolio
Customers
Control
Is final portfolio
super-efficient?
Product
Active Portfolio
Product
Passive Portfolio
Data
Feedback
Feedback
Feedback
Control
Is alpha positive?
Data
Feedback
Data
Passive Portfolio Manager
Form passive portfolio
at minimum cost
Feedback
Control
Is correlation
with market 1?
Feedback
Feedback
Data
Macro Analyst
Estimate
E( R
M
), σ(M)
Forecasts
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