will be unable to compensate creditor’s right. On the
other hand, even the customer maintenance ratio for
a stock looks good and everything seems normal, yet
there still is a hidden worry of higher centralization.
At this moment, if that stock falls suddenly and
rapidly, it might cause a severe loss to the customers
and affect the creditor’s right of security dealer.
Most current securities brokers count on their
account systems to present statistic data after closing
quotation which has the following shortcomings:
In the aspect of data integration: Users have to
check several reports (forms) in order to have an
overall understanding of current status.
In the aspect of portability: It is inconvenient for
the manager of margin trading to carry the forms
everywhere to discuss with others or report to a
superior when an anomaly is found.
To alert the anomaly of key indexes: The closing
form is usually used to make account check and
is hard to alert for the anomaly.
To judge the trend of some key indexes: The
margin trading manager cannot know the
previous data simply from today’s account
balance (need comparisons to historical data).
Thus, our objective of this study is to design and
implement an Executive Information System (EIS)
for managing the risk of margin purchase and short
sale of securities. We will first construct a data
warehouse for margin trading of securities brokers,
and then choose KPIs (Key Performance Indicators)
and analysis dimensions according to practical
requirements for the data cube to be analyzed using
OLAP (Online Analytical Processing) technique
(Chaudhuri and Dayal, 1997; Inmon, 1996; Turban
and Aronson, 2001). Note that MDX (Spofford,
2001) is used in this study to inquire cube data.
2 SYSTEM DESIGN
2.1 Data Model Setup
Three dimensions are required as shown in Table 1:
Customer Dimension: The entire company data
is used to query situation of all customers to
understand current quality of margin loan. Since
customers and the trading volume are different in
different locations, with the branch level we can
compare business performance of each branch.
For the level of customer account, the analysis
target is a single customer.
Table 1: Structures for the dimension hierarchy.
Stock Dimension: By matching with other
dimensions, the level of all shares can be used to
inquire the entire situation of all stocks. Stocks
of the same class might not have the same
operating status, yet their natures might be the
same. The level of securities code is the
individual stock. With the account number, it can
reveal data for balance of stock loan and margin
loan of the stock held by that customer.
Time Dimension: It is necessary for analyzing
time variation of the balance of margin loan.
Since the data processed in our system is
balance, “day” is most popularly used. The other
two are used to calculate mean value.
2.2 Data Warehouse Establishment
In this study, we need one Fact Table and three
Dimension Tables to finish data cube for the OLAP.
Note that according to this study’s measurement
indexes shown in Table 2, the measurements for the
Fact Table will be defined.
Fact Table: Based on the Balance of Margin and
Stock Loan file of the customers in the account
system, it transforms directly the branch code,
customer’s account, security code, balance of
margin purchase, balance of margin loan,
balance of short selling, balance of collateral and
balance of margin of stock loan, and adds some
fields such as that of shareholding ratio and
market share, etc.
Stock Dimension Table: Based on the main
securities file, it transforms the security code,
stock name, security class stocks and market
type, and imports the field of Balance of Margin
Loan from the external data form.
Customer Dimension Table: Based on the main
file of customers, it transfers directly the
company’s code, customer’s account, customer’s
name and executive code.
Time Dimension Table: To avoid the error of
placing the date information of non-trading day,
this table will use system date as the format for
data transformation.
Dimension Structure Details
Customer Star Schemas Entire Company ->
Branch -> Account No.
Stock Star Schemas All Shares -> Securities
Class Stocks ->
Securities Code
Time Star Schemas Year -> Month -> Day
AN EXECUTIVE INFORMATION SYSTEM FOR SECURITIES BROKER’S RISK MANAGEMENT WITH DATA
WAREHOUSING AND OLAP
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