Floor trading and screen trading : distinctions for practitioners

The creation of an electronic limit order book is discussed as the basis for distinguishing between the floor trading and screen trading of derivative instruments. Distinguishing between FTP and ETP in terms of market transparency allows investors to contemplate the trade-off between the 2 platforms. Distinguishing between FTP and ETP in terms of memory preservation allows practitioners to contemplate the different experiences when analyzing floor data and screen data. A comparable set of floor and screen data is used to examine the impact on the trading dynamics and price discovery of LIFFE's FTSE 100 index futures market when trading is automated on LIFFE CONNECT. The dynamics in the quote change equation is shortened when moving from the floor to screen sample. Using the model's measure of trade informativeness, it is found that in 4 out of 5 daily sub-samples, screen trades are more than twice as informative as floor trades. Variability within a system of equations is explained more by order size history than trade size history.

Thermal behavior of copper processed by ECAP with and without back pressure

Samples of electrolytic tough pitch (ETP) pure copper were subjected to 12 passes of Equal-Channel Angular Pressing (ECAP) at room temperature with and without back pressure. Subsequent annealing was performed to evaluate the influence of back pressure during ECAP on the thermal behavior of ultrafine-grained copper. The microstructural and hardness changes caused by annealing were characterized by orientation imaging microscopy (OIM) and microhardness measurements. The application of back pressure resulted in an earlier drop in hardness upon annealing, which is believed to be associated with a lower critical temperature for the initiation of recrystallization and a rapid coarsening of microstructure. Regardless of whether back pressure was applied or not, structure coarsening during short-time annealing of ECAP-processed copper was governed by discontinuous static recrystallization. This is seen as a result of microstructure heterogeneity. Analysis of recrystallization kinetics was carried out based on observations of the microstructure after annealing in terms of the Avrami equation. The magnitude of the apparent activation energies for recrystallization in the absence of back pressure and in the case of back pressure of 100 MPa was estimated to be ~99 kJ/mol and ~91 kJ/mol, respectively. The reasons for reduced activation energy in the case of processing with back pressure are discussed.