Often used in risk arbitrage. Takeoverbid in which the acquireroffers to pay a set price for all outstanding shares of the target company, or any part thereof; contrasts with two-tier bid. Any-part-of order In context of general equities, order to buy or sell a quantity of stock in pieces if necessary. Antithesis of an all-or-none order (AON). Appraisal ratio The signal-to-noise ratio of an analyst'sforecasts. The ratio of alpha to residualstandard deviation. Appraisal rights A right of shareholders in a merger to demand the payment of a fair price for their shares, as determined independently. Appreciation Increase in the value of an asset. Appropriation request Formal request for funds for capital investment project. Approved list A list of equities and other investments that a financial institution or mutual fund is allowed to invest in. See: Legal list. APS Auction Preferred Stock. A type of Dutch Auction Preferred Stock (Goldman Sachs product). Arbitrage The simultaneous buying and selling of a security at two different prices in two different markets, resulting in profits without risk. Perfectly efficient markets present no arbitrage opportunities. Perfectly efficient markets seldom exist, but, arbitrage opportunities are often precluded because of transactionscosts. Arbitrage bonds Municipalityissuedbonds issued intended to gain an interest rate advantage by refunding a higher-rate bond in ahead of their call date. Lower-rate refunding issue proceeds are invested in Treasuries until the first call date of the higher-rate issue. Arbitrage-free option-pricing models Yield curve option-pricing models. Arbitrage Pricing Theory (APT) An alternative model to the capital asset pricing model developed by Stephen Ross and based purely on arbitrage arguments. The APT implies that there are multiple risk factors that need to be taken into account when calculating risk-adjusted performance or alpha. Arbitrage Trading Program (ATP) See: Program trading. Arbitrageur One who profits from the differences in price when the same, or extremely similar, security, currency, or commodity is traded on two or more markets. The arbitrageur profits by simultaneously purchasing and selling these securities to take advantage of pricing differentials (spreads) created by market conditions. See: Risk arbitrage,convertible arbitrage,index arbitrage, and international arbitrage. Are you open? Used in context of general equities. "Can a new customer still participate on opposing side of the trade from that which the first customer initiated?", Inquiring as to whether any portion of that trade is still available See: Open. Arithmetic average (mean) rate of return Arithmetic mean return. Arithmetic mean return An average of the subperiod returns, calculated by summing the subperiod returns and dividing by the number of subperiods. Arizona Stock Exchange A single price auction exchange for equity trading that allows anonymous buyers and sellers to trade at low transactioncosts. Arm's length price The price at which a willing buyer and a willing unrelated seller would freely agree to transact or a trade between related parties that is conducted as if they were unrelated, so that there is no conflict of interest in the transaction. Arms index Also known as a TRading INdex (TRIN). The index is usually calculated as the number of advancing issues divided by the number of