IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => GCE AS & A2 Level => Math => Topic started by: sweetie on April 20, 2010, 06:18:44 pm

Title: CIE AS statistics
Post by: sweetie on April 20, 2010, 06:18:44 pm: cud sum1 tell me when do we use the continuity factor in the normal distribution calculations????
Title: Re: CIE AS statistics
Post by: immortal on April 20, 2010, 06:32:59 pm: A continuity factor is used when you use a continuous function to approximate a discrete one; when you use a normal distribution table to approximate a binomial, you’re going to have to use a continuity correction factor. It’s as simple as adding or subtracting.
Dat is we u find da mean & S.D from X ~ B(n,p) den mean=np & Var(X)=np(1-p)
Title: Re: CIE AS statistics
Post by: sweetie on April 20, 2010, 06:59:59 pm: Thank You :D

cud u also tell me when do we know if order matters or no??

check Q4
Title: Re: CIE AS statistics
Post by: immortal on April 20, 2010, 07:32:13 pm: 4 Permutations(P) the order matters dat is, as per question 4) each passenger is unique & da word "arrangement" is specified, as 4 Combinations(C) the order does not matter.
as fo part iii> dey asked how da passengers can b "chosen" so v shud solve using combination.
Title: Re: CIE AS statistics
Post by: sweetie on April 20, 2010, 08:53:30 pm: Thank You :)
Title: Re: CIE AS statistics
Post by: sweetie on April 21, 2010, 04:11:14 pm: cn u tell me , whether the mean or the standard deviation in normal distribution cn be neg.???????

nd when we say: "........that there r 90 or fewer tapes....."
do i take the continuity factor as 90.5 or 89.5???
Title: Re: CIE AS statistics
Post by: sweetie on April 21, 2010, 10:14:36 pm: Quote from: sweetie on April 21, 2010, 04:11:14 pm
cn u tell me , whether the mean or the standard deviation in normal distribution cn be neg.???????

nd when we say: "........that there r 90 or fewer tapes....."
do i take the continuity factor as 90.5 or 89.5???