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#1




What would an increase in a sample size change?
A study to examine the association between a suspected dietary nutrient and stomach cancer fails to find a significant association. If the investigators repeat the study with a larger sample size, in what way is this result likely to change?
a) The probability of concluding that a chance association is not statistically significant will decrease b) The probability of concluding that a chance association is statistically significant will decrease c) The probability of a falsenegative statistical test will be greater d) The statistical power of the study will be greater e) The study's effect size will decrease 
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#3




Yes statistical power of study will increase.
Just ready this point today somewhere. If we flip coin 4 times then we have chances that may be we get 1 heads or 50% heads or even more. So it varies in small no. Of population drastically. Whereas if we flip coin 10,000 times then chances of getting heads would be approx 50%. I know it's not an ideal example but you can figure out that with change in total no. Of people stats results varies a lot. Sent from my iPad using Tapatalk HD
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#4




d is correct

#5




D due to PPV
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#6




a) The probability of concluding that a chance association is not statistically significant will decrease
or d) The statistical power of the study will be greater 
#7




correct answer
The answer is d) The statistical power of the study will be greater
The power of a statistical test is the probability that a conclusion of statistical significance is correct (i.e., the probability of a truepositive result). Statistical power is determined by effect size, α level, and sample size. If the other factors remain constant, increasing sample size will increase statistical power. As for A)  This is a truenegative result with a probability of (1 – α). α, and therefore (1 – α), is predetermined by the investigator, usually at 5%, and is not changed by increasing sample size. As for B)  This is a falsepositive result, with a probability of α. Before the study, the investigator sets the α level, usually at 5%, which is not changed by the sample size. 
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