pearljam59
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There was a bar graph included in this question that showed an INCREASING measure (similar to a NEGATIVE SKEW with a tail on the left) However, the last measurement on the right was the highest point on the graph so therefore I do not know if it can still be considered a negative skew becuase measurements DIVE DOWN right after the highest point! For this graph think of a graph rising exponentially with a tail on the left.
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)
In thinking that this is a negative skew but B and D are the same answer. A and C refer to a positive skew. I want to say E but you can still determine mean median mode even if it is NOT a normal Gaussian bell shaped distribution (ie positve and negative skews as well as bimodal).
Sorry hard to explain if you have not seen the question.
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| tolito
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i do not yet master this topic but for a negatively skewed graph, the median is larger than the mean. that is all the information in kaplan. no mention of mode. so i will go with B.
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| mohelgamal
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Althoough I am not great at biostatistics here is the answer
the mode the value that is repeated the most here it is 1
the median is the value that stand bet equal number of cases in each side (here 5 above and 5 below) which is also equal to 1
mean is the summation of all values divided by the number of cases here it is 2
so mean is larger than median here
so it is A
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| jamdoc
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A
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| josephmedman
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i thought that too at first..but you dont take the median of the patient..you take the median of the values..values range from 0.0 to 5.5..median would be 3.0..so it is B as the answer..its like if you have 20 test papers..you dont take the 10th test paper as the median..you would put all the scores down..and then choose the middle score..just like here..you choose the middle serum creatinine...
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| Musuq
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ok I got the picture pearljam
49. 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?
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| MRMAVERICK
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wats answer
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| jamdoc
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agree with mohelgamal
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| NE
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D
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| Ancylostoma
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in a normal distribution mean median and mode will be the same. In skewed distribution, mean will be closest to the tail, mode furthest from the tail, and median in the middle. This is why the best measure of central tendency in a skewed graph is not mean, but mode. logicaly think of it this way if all the numbers were <5 except one that was 1000. The mean would be a large number and would be a porr measure of central tendency. The median on the otherhand would be in the middle and thats what you looking for.
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| jedw
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It's A - the mean is about 1,6 while the median is 1
You cannot read the mean, mode and median from the graph above directly
because it doesn't show the distribution of values
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| laura81
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median and mode are equal =1....so the answer is B
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| lq2006
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B
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| Addicudo
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B definitely !
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| ssrpk
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well, it is not a distribution of different values around a particular mean, so skewness of the distribution can not be validated. [ all of the cases are presented on this graph, therefore it will always look like a negatively skewed curve]
i agree with mohelgamal, its A
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| Addicudo
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 ... Yes it indeed is .. !! Cannot access it as a Gussaian curve .. !! A then .. ! Thankz!
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| lq2006
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A NEGATIVE SKEW HAS A TAIL TO THE LEFTAND THE MEDIAN GREATER THAN THE MEAN.
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| Hebbe-Indy
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The graph is not a graph of distribution (which is what First Aid is talking about when it says a negatively skewed graph has hump on left and has meanA is the answer
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| Hebbe-Indy
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I think that part of my post got erased as my cat walked over my laptop as I was just about to post.
Wanted to say that this is not a graph of distribution (which what First Aid is talking about when it says that a negatively skewed graph with a hump on the left has mean< medianThis graph has each patient on x axis and lab values on y axis
A graph of distribution would have lab values on x axis and number of occurences of that lab value on y axis.
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