Bio 201 Introduction to Biology 1, Section 53

Lab Report #1: Introduction to Summary Statistics

Elizabeth Hegedus

BIO 201 Introduction to Biology 1, Section 53

September 18, 2012

Courtney Brennan

1.)

        a.) 2, 4, 5, 6, 7, 12       2+4+5+6+7+12=36   36/6=6              5+6=11       11/2=5.5 Mean=6; Median= 5.5

b.) 2, 4, 5, 7, 8, 12, 26      2+4+5+7+8+12+26=64       64/7=9.14             median=middle number      Mean=9.14; Median=7

c.) 113, 124, 124, 132, 146, 151, 170      113+124+124+132+146+151+170=960     960/7=137.14        median=middle number      Mean=137.14; Median=132

d.) 1, 2, 10, 11, 13, 19      1+2+10+11+13+19=56        56/6=9.333333…        10+11=21

21/2=10.5          Mean=9.33333…; Median=10.5

2.)

        a.) mean=6     1-6=-5    3-6=-3    5-6=-1    9-6=3    12-6=6    (-5)^2 =25    (-3)^2=9  

(-1)^2=1        3^2=9    6^2=36    25+9+1+9+36=80    80/5-1= 80/4= 20    square root of 20= 4.47    Variance=20; standard deviation=4.47

        b.) mean=73    76-73=3    72-73=-1    65-73=-8    70-73=-3    82-73=9    squares of all values = 9, 1, 64, 9, and 81.    9+1+64+9+81=164    164/5-1= 164/4= 41    square root of 41= 6.40    Variance=41; standard deviation=6.40

        c.) mean=12    4-12=-8    8-12=-4    12-12=0    16-12=4    20-12=8    squares of all values = 64, 16, 0, 16, and 64.    64+16+0+16+64=160    160/5-1= 160/4= 40     square root of 40= 6.32 Variance=40; standard deviation=6.32

3.)

        a.) 2, 4, 6,10, 14, 24, 25, 25, 28, 50, 70, 71, 82    Median=25    Median of lower half= 8

Median of upper half= 60    60-8 = IQR=52

        b.) 113, 124, 124, 132, 146, 151, 170    Median=132      Median of lower half= 124

Median of upper half= 151    151-124 =IQR=27