Slippage is the difference between the expected price of a trade, and the price the trade actually executes at. Slippage often occurs during periods of higher volatility, when market orders are used, and also when large orders are executed when there may not be enough interest at the desired price level to maintain the expected price of trade. In forex, slippage occurs when a limit order or stop loss occurs at a worse rate than originally set in the order. Slippage in the trading of stocks, often occurs when there is a change in spread. In this situation, a market order placed by the trader may get executed at a worse than expected price.
Open access to the scientific literature means the removal of barriers (including price barriers) from accessing scholarly work. There are two parallel roads towards open access: Open Access articles and self-archiving. Open Access articles are immediately, freely available on their Web site, a model mostly funded by charges paid by the author (usually through a research grant). The alternative for a researcher is self-archiving (i.e., to publish in a traditional journal, where only subscribers have immediate access, but to make the article available on their personal and/or institutional Web sites (including so-called repositories or archives)), which is a practice allowed by many scholarly journals.
Open Access raises practical and policy questions for scholars, publishers, funders, and policymakers alike, including what the return on investment is when paying an article processing fee to publish in an Open Access articles, or whether investments into institutional repositories should be made and whether self-archiving should be made mandatory, as contemplated by some funders.
Last date updated on June, 2014