Question

1. The following data set is given. Determine whether it is reasonable to treat the following sample as though it comes from an approximately normal population. Include any charts or graphs you make in Excel here and justify your answer.

8.8	11.2	11.6	6.3	9.3	10.5	14.6	8.5	7.3
7.5	5.2	9.0	4.3	9.9	7.8	13.1	12.3	10.1

Answer 1

Sol:

select the data go to

Insert>Histogram

You get

From Histogram sample follows skewed distribution

For the given sample get the descriptive statistics in excel

Data>Data analysis >Descriptive statistics

You get

SAMPLE
Mean	8.85
Standard Error	0.793159
Median	9.15
Mode	#N/A
Standard Deviation	3.365089
Sample Variance	11.32382
Kurtosis	0.648267
Skewness	-0.58879
Range	13.8
Minimum	0.8
Maximum	14.6
Sum	159.3
Count	18

mean=8.85

median=9.15

mean<median

Negatively skewed .

Also from skewness coeffcient ,-0.59,its negatively skewed.

  it is not reasonable to treat the following sample as though it comes from an approximately normal population.