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#1




Mean, Median, Mode
As a part of a study to determine factors influencing mortality in an intensive care unit, serum creatinine concentrations (in mg/dL) are obtained from 10 consecutive patients at the time of admission to the intensive care unit. The results are shown in the graph. Which of the following statements regarding the sizes of the mean, median, and mode of the serum creatinine values is correct?
A. The mean is larger than the median B. The median is larger than the mean C. The median is larger than the mode D. The mode is larger than the median E. The mean, median, and mode cannot be determined because the distribution is not normal (gaussian) click image to enlarge Please explain the answer... 
#2




A is my answer.
correct me if im wrong. the 10 values are  0.5 0.5 0.5 1 1 1 1 2 4 5 mean  8.3 MOde (MOst number)  1 MEDian (MIDdle number)  in this case 1+1/2 = 1. 
#3




Negative skew it looks like
SO the answer is C. Median > mode. MAY BE WRONG Last edited by mdsoon; 03132013 at 01:32 PM. 
#4




Quote:
While positive skewed will be Mean > Median > mode ??? So if thats the case , the answer should be D. 
#5




if it is positive skew option A and D are correct.
if it is negative skew option B and D are correct. yes/no? 
#6




now 'im even more confused
so whats the right answer? 
#7




i think its A based on my calculation. but i dont know if thats the right method to use.

#8




PLZ help
I don't know the answer. I think A might be correct, but some believe that B might be correct. This is a NBME Q. http://www.usmleforum.com/files/forum/2009/1/444772.php

#9




that post was made in 2005 and still nobody knows the answer.. LOST CAUSE MAYBE..
take it as a WFT question and move on. 
#10




Quote:

The above post was thanked by:  
succinylcholine (03132013) 
#11




THE ANSWER IS B, because negatively skewed plots the median is greater than the mean

#12




Quote:
Which makes me think maybe the last choice us correct? So i looked up whats Gaussian distribution, only found out that its the normal distribution, which contradicts whats mentioned in that last choice =s http://hyperphysics.phyastr.gsu.edu/%E2%80%8Chbase/math/gaufcn.html#c2 http://www.thefreedictionary.com/_/dict.aspx?word=Gaussian+distribution 
#13




@doctor ali  what is the "specific:  is it a medical term used in these graph situations or something else?
@faith  well your work of looking it up paid off as something right.im done for today.see you guys tomoro. 
#14




A. The mean is larger than the median
I believe that's the right answer. The plot/graph given is not a frequency plot; I mean the yaxis is not the frequency of ppl who have a certain creatinine value, it's the actual raw value of their creatinine level. We simply add up the values and divide by 10 (total number of ppl/values to get the mean), and of course the median is the value in the middle in ascending order. If instead of having creatinine concentration on the yaxis, we had number of ppl (frequency), and we had on the xaxis creatinine values. Then this graph would be negatively skewed, and mode>median>mean could apply.
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To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts. You can't confuse the confused! To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts. Last edited by slowpoke; 03132013 at 09:47 PM. 
#15




alaskaa
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#16




Quote:
I mean general speaking vs. specific speaking. In negative skewed: General speaking: Mode > Median > Mean Specific speaking: Median > Mean In positive skewed: General speaking: Mean > Median > Mode Specific speaking: Mean > Median In most cases, they want specific speaking answers. 
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BiostatisticsEpidemiology, Figures, Step1Questions 
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