Hi,

I'm new to Mata and I'm still getting my feet wet, so apologies if this is a dumb question.

I'm a little confused about some of the terminology, particularly with respect to the -cross- function.

The manual states that this computes matrix multiplication of the form X'X.

My question is this: Is this a common use of the term cross product? I've only learned cross product as the product of two vectors that produces a third, orthogonal vector (as in https://en.wikipedia.org/wiki/Cross_product). Is this just a terminology issue or is there something that I'm missing about how those two relate to one another? I've noticed similar uses of the term cross product in Cameron & Trivedi's Microeconometrics text.

Thanks in advance.

I'm new to Mata and I'm still getting my feet wet, so apologies if this is a dumb question.

I'm a little confused about some of the terminology, particularly with respect to the -cross- function.

The manual states that this computes matrix multiplication of the form X'X.

My question is this: Is this a common use of the term cross product? I've only learned cross product as the product of two vectors that produces a third, orthogonal vector (as in https://en.wikipedia.org/wiki/Cross_product). Is this just a terminology issue or is there something that I'm missing about how those two relate to one another? I've noticed similar uses of the term cross product in Cameron & Trivedi's Microeconometrics text.

Thanks in advance.

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