Exercise 8.3. Suggest a Financial Service Industry Algebra. A.3 Financial Service Industry We refer to Appendix A, Sect. A.3, Financial Service Industry A, or the, financial service industry (of a country, of a region, or of the world) consists of banks, insurance companies, securities instrument brokers and (stock) exchanges, as well as of portfolio management and other financial market operators. Suggest short sort (or type) nams for the Financial Service Industry, in particular Bank entities (Customer, Bank Account, etc.), and signatures for (four) functions that open and close accounts, that establish shared accounts, that deposit and withdraw funds, and that transfer funds between accounts. (Remember to also identify the types of such internal bank "books" that keep track of customers account numbers, and of the sharing of accounts.) Write out axioms, in English, stating properties that must hold of any input argument or result value amongst the many financial service industry entities. "Wrap" the whole thing into a scheme declaration In banks customers can open and close accounts, deposit and withdraw funds, establish and terminate loans, borrow ("against") and pay back loans etc. A customer may have several deposit and/or loan (and/or other) accounts A.3 Financial Service Industry 565 Several customers may share accounts. Funds may be transferred between accounts in same or different banks. Customers may request (order) the buying or selling of securities instru- ments through a broker (to be transacted at a securities instrument (g stock) exchange. A "buy" [sell'] request names a securities instrument, states time interval of request being valid (i.e, during which it should, if possible, be effected), states price interval ("lo, hi) within which transaction should, if possible, be effected (with "hi" [%"], for bay, ['sell'] orders, dsignating an absolute limit, while the "lo ['hi] being an "OK, you may effect transaction limit). The lacing of a buy or sell order results in the exercise of a unique order code (to be retained by the customer and broker). At a securities instrument (eg.. stock) exchange several buy and sell orders may have associated (over- lapping) time and price intervals such that transaction can be concluded (by traders). If an order cannot be effected it is withdrawn. Customers may direct funds from or to bank accounts (and is so stated in placed orders). A set of buy and sell orders naming the same securities instrument may constitute the basis for a transaction. The sum of the sell quantities must "be close or equal to the sum of buy quantities; the time of the transaction must be within the time intervals stated in all these orders; and the transacted price must within the price intervals stated in all these orders. Which transactions are eventually concluded is not a computable decision. It is ("highly") nondeterministic to some even chaotic. In the set of exercises related to this topic we forgo any consideration of Exercises related to this topic are: 2.8, 3.5, 4.6, 5.1, 5.2, 5.3, 8.3,9.3, 10.4, Examples 9.10 and 9.14 also relate to this exercise topic. other than banks, brokers and exchanges (incl. traders). 11.3, 12.6, 13.7, 14.8,15.17,16.14, 18.3, 19.6, 20.6, and 21.14 Exercise 8.3. Suggest a Financial Service Industry Algebra. A.3 Financial Service Industry We refer to Appendix A, Sect. A.3, Financial Service Industry A, or the, financial service industry (of a country, of a region, or of the world) consists of banks, insurance companies, securities instrument brokers and (stock) exchanges, as well as of portfolio management and other financial market operators. Suggest short sort (or type) nams for the Financial Service Industry, in particular Bank entities (Customer, Bank Account, etc.), and signatures for (four) functions that open and close accounts, that establish shared accounts, that deposit and withdraw funds, and that transfer funds between accounts. (Remember to also identify the types of such internal bank "books" that keep track of customers account numbers, and of the sharing of accounts.) Write out axioms, in English, stating properties that must hold of any input argument or result value amongst the many financial service industry entities. "Wrap" the whole thing into a scheme declaration In banks customers can open and close accounts, deposit and withdraw funds, establish and terminate loans, borrow ("against") and pay back loans etc. A customer may have several deposit and/or loan (and/or other) accounts A.3 Financial Service Industry 565 Several customers may share accounts. Funds may be transferred between accounts in same or different banks. Customers may request (order) the buying or selling of securities instru- ments through a broker (to be transacted at a securities instrument (g stock) exchange. A "buy" [sell'] request names a securities instrument, states time interval of request being valid (i.e, during which it should, if possible, be effected), states price interval ("lo, hi) within which transaction should, if possible, be effected (with "hi" [%"], for bay, ['sell'] orders, dsignating an absolute limit, while the "lo ['hi] being an "OK, you may effect transaction limit). The lacing of a buy or sell order results in the exercise of a unique order code (to be retained by the customer and broker). At a securities instrument (eg.. stock) exchange several buy and sell orders may have associated (over- lapping) time and price intervals such that transaction can be concluded (by traders). If an order cannot be effected it is withdrawn. Customers may direct funds from or to bank accounts (and is so stated in placed orders). A set of buy and sell orders naming the same securities instrument may constitute the basis for a transaction. The sum of the sell quantities must "be close or equal to the sum of buy quantities; the time of the transaction must be within the time intervals stated in all these orders; and the transacted price must within the price intervals stated in all these orders. Which transactions are eventually concluded is not a computable decision. It is ("highly") nondeterministic to some even chaotic. In the set of exercises related to this topic we forgo any consideration of Exercises related to this topic are: 2.8, 3.5, 4.6, 5.1, 5.2, 5.3, 8.3,9.3, 10.4, Examples 9.10 and 9.14 also relate to this exercise topic. other than banks, brokers and exchanges (incl. traders). 11.3, 12.6, 13.7, 14.8,15.17,16.14, 18.3, 19.6, 20.6, and 21.14