c什么意思

问题如下：

Alex has been assigned to use DataCorp's extensive data collection to develop a machine learning (ML) model. This model will apply advanced statistical methods to uncover data structures and relationships.

When is Alex's model likely to be most effective?

选项：

A.

for exploring new markets.

B.

in a market that is well understood.

C.

during times of heightened market volatility.

解释：

B is correct. Many trading problems are ideally suited for machine learning analyses because the problems repeat regularly and often. For such problems, machine-based learning systems can be extraordinarily powerful. However, these systems are often useless—or worse—when trading becomes extraordinary, as when volatilities shoot up. Machine learning systems frequently do not produce useful information during volatility episodes because they have few precedents from which the machines can learn. Thus, traders often instruct their electronic trading systems to stop trading—and sometimes to close out their positions—whenever they recognize that they are entering uncharted territory. Many traders shut down when volatility spikes—both because highvolatility episodes are uncommon and thus not well understood and because even if such episodes were well understood, they represent periods of exceptionally high risk.