Question

1. Decide the best measurement of central tendency for each data set. Justify your answer.

Area codes:                     201        973         973         212         201	609
973         973         201         973         973	212
Best measurement is (underline one):   mean       median                                                             Explain why:	mode
SAT scores:                   500        500         520         580         590	600
640         640         640         640         680	700
Best measurement is (underline one):   mean       median                                                             Explain why:	mode
Blood types:                     A           B             AB          O             A	B
AB          O             O             O             O	O
Best measurement is (underline one):   mean       median	mode

Answer 1

Area codes

Mode

As we cannot have mean for area codes as area codes cannot take all the possible values and mean need not necessarily be one of the value which is in the population.

Median does not make sense as it won't matter which area code is to the centre hence mode.

SAT scores

Mean

We are usually interested in knowing the mean score of students and therefore mean in this case would be perfect as it can take all possible values in between the range of values.

Even median can be useful measure but depending upon the situation it may change

Blood types

mode

We are interested in knowing the most common blood type in the population and hence mode is the most suitable way to find it.

Morover we can't arrange the data hence cannot find the median and mean can be computed only for numeric data and this is not numeric.

Thank you !!