mock test question 17

[Sofia Sagar]

dear sir / madam,

 please help me how to calculate outliers . 

i know formula :  if a data value  < q1 - 1.5 iIR

                                                        or > q3 + 1.5 iIR 

i dont get q1 - 1.5 IR part.

 how to calculate it . i am getting   in negatives . is it fine ?

 i am getting  - 12. 5 .

this value is not in data ,so are we saying outliers are not there 

or  should we consider mod 

please help me 

 thank you 

[Sofia Sagar]

also ,  we cant  ever predict what median or mode  is if box plot alone is given without data , right ? 

or can we ?  we cant calculate mean also right ? 

please clarify 

thank you 

[Statistics 1 Support 1]

Hi,

From the boxplot, you can figure out the values of Q1 and Q3, Then IQR will be Q3-Q1. Now check whether there are outliers or not. Q1-1.5IQR can be negative too.

You can't find the mean from the boxplot.

Thanks,

Nitin Jha

Course support team

[Anamika Verma]

Hi Team,

May you please guide on how to calculate the median from the boxplot graph. or How can we validate if the given Median option in the question is correct or not?

Thank you,

Anamika

[Yogendra]

Would like to know if Mode can be calculated from the given box plot + the IQR we would have obtained? i could not find a way how to rule out the fourth option of  

"Mode of the dataset will necessarily lie in [50, 55]"

@Anamika, for the Median it was explained in one of other discussion that the mid value of Q3 (50) and Q1(25) is 37.5 which suggests it can be  median (50th percentile) but not necessarily.

[Akshay Malik]

There can be no inference made on the MODE just by analyzing the BOX PLOT without the actual data.

Median will lie between the Interquartile Range but you cannot calculate it without the actual data.