are exchangeable sequences of real{valued random variables. Suppose thatSn and

Abstract. Consider two exchangeable sequences (Xk)k2N and ( ^ Xk)k2N with the property that Sn P n k=1 Xk and ^ Sn P n k=1 ^ Xk have the same distribution for all n 2 N. David Aldous posed the following question. Does this imply that the two exchangeable sequences have the same joint distributions? We give an example that shows the answer to Aldous ' question is, in general, in the negative. On the other hand, we show that the joint distributionsofan exchangeable sequence can be recovered from the distributions of its partial sums if the sequence is a countable mixture of i.i.d. sequences that are either nonnegativeorhave nite moment generating functions in some common neighbourhood of zero