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#1




Systolic blood pressure and confidence interval
In a random sample of 30 patients from a small city, you have measured the systolic blood pressure (SBP). The 95% conﬁdence interval(CI) for the mean SBP is (122,138).
Which of the following statements gives a valid interpretation of this interval? (a) About 95% of the sample of patiets have a SBP between 122 and 138. (b) About 95% of the of the patients in that city have a SBP between 122 and 138. (c) If the sampling procedure were repeated many times, then approximately 95% of the resulting CI would contain the mean SBP for patients in the city. (d) If the sampling procedure were repeated many times, then approximately 95% of the sample means would be between 122 and 138. (e) The probability that the sample mean falls between 122 and 138 is equal to 0.95. 


#4




Correct Answer: D
I think it should be D, because CI is defined as a Range of values in which repeated means of sample expected to fall... So in order to get the option E i would likely to see option D to conclude with option E.
Correct Answer: D 
The above post was thanked by:  
bebix (05262011) 
#6




Quote:

The above post was thanked by:  
bebix (05262011) 
#10




correct answer
very good!
the correct answer is C) If the sampling procedure were repeated many times, then approximately 95% of the resulting CI would contain the mean SBP for patients in the city. Any one interval from a particular sample may or may not contain the true parameter. In this case, 95% of such intervals that could be constructed from repeated random samples of size n contain the true parameter (in this case μ). In other words: We are 95% confident (or there is a 95% certainty) that the interval contains the "true" parameter (e.g. population mean) We are 95% confident that the true parameter is between [lower bound] and [upper bound] and as Casandra said, 95% CI does not equal 95% probability. 
The above post was thanked by:  
Claus_CU (05262011), donofitaly (05272011), prataptetali (05272011), rulz (05262011), usluipek (05262011) 
#12




do u have more questions like this one???

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BiostatisticsEpidemiology, Step1Questions 
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