在异方差条件下普通最小二乘法具有如下性质（）

对回归模型存在异方差问题的主要处理方法有（）。

叙述异方差性的概念、后果和补救措施。

什么是城市经济学，阐述城市经济学产生的原因、并阐明城市经济学是空间经济学和中观经济学。

Every deliberate act of wrongdoing by the master or any of the crew against the ship or cargo，without the authorization or privity of the Shipowner or his agent，is（）.

（）, or drum is used for hauling in or letting out the wires or ropes which will fasten the ship to the shore.

A salvor may be（）the whole or part of the payment due under Salvage Convention to the extent that the salvage operations have become necessary or more difficult because of fault or neglect on his part or if the salvor has been guilty of fraud or other dishonest conduct.

The （） is used for hauling in or letting out the wires or ropes.

Vessels must be（）valid certificate of nationality or certificated of registry or license.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

下列关于异方差性检验的叙述，正确的是（）。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。