In: Statistics and Probability
The following weights are for 16 Grizzly Bears in North America. They are:
125, 114, 108, 135, 144, 124, 110, 152, 134, 117, 98, 116, 202, 225, 169, 160
X | x- | (x-)2 | |
1 | 98 | -41.5625 | 1727.441 |
2 | 108 | -31.5625 | 996.1914 |
3 | 110 | -29.5625 | 873.9414 |
4 | 114 | -25.5625 | 653.4414 |
5 | 116 | -23.5625 | 555.1914 |
6 | 117 | -22.5625 | 509.0664 |
7 | 124 | -15.5625 | 242.1914 |
8 | 125 | -14.5625 | 212.0664 |
9 | 134 | -5.5625 | 30.94141 |
10 | 135 | -4.5625 | 20.81641 |
11 | 144 | 4.4375 | 19.69141 |
12 | 152 | 12.4375 | 154.6914 |
13 | 160 | 20.4375 | 417.6914 |
14 | 169 | 29.4375 | 866.5664 |
15 | 202 | 62.4375 | 3898.441 |
16 | 225 | 85.4375 | 7299.566 |
Total | 2233 | 0 | 18477.94 |
Find the Mean, Median, Range and Population Standard Deviation to the nearest tenth.
Mean | 139.5625 |
Median (2nd quartile) | 129.5 |
Range (Max - Min) | 127 |
Pop SD | 33.983 |
Find the Z-Score of the female bear that weighs 134kg
z-score =
x = 134
z-score = -0.1637
Make a box and whisker plot.
For the five point summary we need min,Q1,Q2,Q3,max. Where the quartiles use the following formula
th value | value | |
Q1 | 4.25 | 114.5 |
Q2 | 8.5 | 129.5 |
Q3 | 12.75 | 158 |
Summary
Min | 98 |
Q1 | 114.5 |
Q2 | 129.5 |
Q3 | 158 |
Max | 225 |
Determine if there are any outliers in your plot. FIND IQR.
To check for outlier we see if any value falls outside the range (Q1-1.5IQR, Q3 - 1.5IQR) where IQR = Q3-Q1
IQR = 43.5
range = (49.25, 223.25)
Outliers : 225
Determine the shape of the distribution.
Since the median line is to the left and there is space towards the right also Mean > Median, so it right or positively skewed.