Hi John, how do we know when to use the formula for population variance and when to use the formula for sample variance? I.e. when do we know to divide just by n or by n-1 when calculating variance? TIA!

Sampling theory (which Is what this question seems to be referring to) is not in the syllabus for Paper MA. It used to be a long time ago, but that is many years ago now 馃檪

There are none. However there will be lots of questions in your Revision Kit (and it is absolutely essential that you have a Revision Kit from one of the ACCA approved publishers because they are full of exam standard questions for practice).

ebates29 says

Hi John, how do we know when to use the formula for population variance and when to use the formula for sample variance? I.e. when do we know to divide just by n or by n-1 when calculating variance? TIA!

John Moffat says

Sampling theory (which Is what this question seems to be referring to) is not in the syllabus for Paper MA. It used to be a long time ago, but that is many years ago now 馃檪

boojie2001 says

SORRY TO SAY BUT I GUESS U GOT THE ANSWER OF SIGMA X-X2 WRONG IT IS 17514428 NOT 17694428

John Moffat says

True – I must re-record the lecture. However the printed answer in the lecture notes is correct 馃檪

Thanks.

(Please don’t type in capitals 馃檪 )

Hilal380 says

Excuse me sir, I cant find practice questions of this chapter.

John Moffat says

There are none. However there will be lots of questions in your Revision Kit (and it is absolutely essential that you have a Revision Kit from one of the ACCA approved publishers because they are full of exam standard questions for practice).

Mitiksha says

Sorry to ask but how is Arithmetic Mean $1817 worked out?

John Moffat says

I show the calculation in the previous lecture working through example 2 in this chapter !!!