Portfolio Optimization
In this assignment you will be using Dynamic Programming to select a set of investments
options that maximize your return on investment. You will be given a file of investment options
along with the estimated return on investment for each one. You also have a given amount of
money to invest. The specific file of investment options you will be given will vary, but you will
always have the following 3 pieces of information you can obtain from the file:
InvestmentName, Investment Cost, Estimated ReturnOnInvestment
For example:
A, 10, 60
B, 20, 100
C, 30, 120
Start by putting all your code in a file called portfolio.py. Create a function called
loadInvestments that takes in the investmentFilename and returns a list of possible investment
options: name, cost, and estimated return. You will be given a file of actual investment options
along with specific directions for that file on how to obtain the 3 pieces of information
necessary for this assignment.
Then make a function called optimizelnvestments that takes the list of possible investments
along with the amount of money available to spend. This function should return both the
optimal return on investment amount as well as the actual investments selected to achieve this
optimal. Implement this function using Dynamic Programming.
For Dynamic Programming, one needs a recursive breakdown of the problem. We have a
number of possible investments and an amount we are able to spend. At each step we can
decide to either include investment x or exclude it. If we include it, then we are left with a
smaller problem of finding the optimal with all the possible investments without investment x
with a smaller amount we are able to spend (because we purchased investment x). If we
exclude it, then we are left with a smaller problem of finding the optimal with all the possible
investments without investment x, but with the same amount of money to spend as we had
before.
A DAC solution could be attempted, but it ends up having too much repeated work. So we will
implement our solution with Dynamic Programming. Note that this is a 2D problem (number of
investments and amount of money to spend). Thus, we will need a 2D table. The second step
is filling in the base-cases. Note that when we don't select any investments, no matter how/nmuch money we have to spend (top-row) then we get no return on investment. So this is a
natural base-case. The third step is to identify the goal location in the table. This will be the
position where we are allowed to include all investments with our full allocation of funds to
spend. This will be the lower right corner. The last step in computing any optimal table is to
determine the order to fill in the table, keeping in mind that one always needs all the results for
the recursive sub-problems available in order to fill in the next location.
Once the optimal table is computed, a trace-back table needs to be added to the
implementation. This is so we can find the actual investments that produce the optimal. Recall
that trace-back tables store the "winning" options at each step and are then used at the end to
trace-back through these winning options. Your code should return the optimal return on
investment number as well as a list of the investment names used to obtain this optimal
number.
Note that this is a similar problem to the 0/1 Knapsack problem and you should use that idea to
help guide you through your implementation.
Fig: 1
Fig: 2