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Statistics course and homework discussion. Elementary statistics.enThu, 08 Dec 2016 07:56:34 GMTvBulletin60http://www.talkstats.com/images/misc/rss.pngStatistics Help @ Talk Stats Forum - Statistics
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Statins for the primary prevention of cardiovascular disease.
http://www.talkstats.com/showthread.php/67467-Statins-for-the-primary-prevention-of-cardiovascular-disease.?goto=newpost
Wed, 07 Dec 2016 19:30:30 GMTThis is an excerpt from this source and the picture is also from the source. It says that the “JUPITER” study was the only one to show strong evidence of reduction in mortality. My question is with this excerpt and the graph if the “JUPITER” numbers were taken out would the mortality rates be clinically significant? [Edit: Removed link to local file -CB]
]]>Statisticsjohnconnorhttp://www.talkstats.com/showthread.php/67467-Statins-for-the-primary-prevention-of-cardiovascular-disease.<![CDATA[Little problem that I'm struggling to solve...]]>
http://www.talkstats.com/showthread.php/67463-Little-problem-that-I-m-struggling-to-solve...?goto=newpost
Wed, 07 Dec 2016 15:04:01 GMTThe proportion of smokers in a certain population is 25%. What is the probability
that smokers' proportion in a sample of 40 people randomly selected from this
population will be below (strictly less than) 20%.

Surely you would use the binomial table N = 40 P = 0.25 X = 8 (since below 20% = less than 8 people from the sample of 40)

I tried using the binomial table to find P(X<8) then use the binomial equation P(X=8).

So to complete the question I did P(X<8) - P(X=8) = 0.1819.. and I thought 18.19% is the correct answer but I seem to be mistaken? Any help?

The correct answer is 0.2296, why?

Appreciate any help thanks!
]]>Statisticsjackjack583http://www.talkstats.com/showthread.php/67463-Little-problem-that-I-m-struggling-to-solve...Bayes weighted average with example
http://www.talkstats.com/showthread.php/67462-Bayes-weighted-average-with-example?goto=newpost
Wed, 07 Dec 2016 13:43:51 GMTHello. I have 2 movies which need to be compared. Movie 1 - Mean score 92/100 from 2000 votes. Movie 2 - Mean score 80/100 from 4000 votes....Hello. I have 2 movies which need to be compared. Movie 1 - Mean score 92/100 from 2000 votes. Movie 2 - Mean score 80/100 from 4000 votes.
Currently Movie is ranked 1 and Movie 2 is ranked 2. Shoudln't it be the other way round since movie 2 has more votes despite having a low score.
I used bayes weighted average to normalize the ratings and recalculate the grades using the following formula. b(r) = [ W(a) * a + W(r) * r ] / (W(a) + W(r)]
where r = average rating for an item W(r) = weight of that rating, which is the number of ratings a = average rating for the entire data set of 5 products. W(a) = weight of that average, which is the average number of ratings for all the 5 products, and Bayes(r) = new bayesian rating
For the above example , a = 0.84 i.e weighted mean of movie 1 and 2. W(a) is 3000 i.e (2000+4000)/2.
The results are as follows. Movie 1 Bayes r : 87/100---- RANK 1 Movie 2 bayes r : 82/100---- RANK 2
Despite the normalization movie 1 still continues to rank higher than movie2 .
Thoughts anyone ?