An alternative model to the LIBOR market model given in Exercise 18(ii) is proposed as follows. Suppose now that, under F, for   where W and σi are as in Exercise 18(ii) and  is a deterministic...

An alternative model to the LIBOR market model given in Exercise 18(ii) is proposed as follows.

Suppose now that, under F, for

where W and σi are as in Exercise 18(ii) and
 is a deterministic function of
 chosen to satisfy

Where

Show that, for i = 1,...,n,

Is this model arbitrage-free? Would this model be easy to implement in practice?