homework 1

Stat381 Homework 1 – due 9/27/2022
1: A psychologist developed a new test of adult intelligence. The test was administered to 20 individuals,
and the follow data were obtained. Construct a stem-and-leaf display for the data.
114
99
131
124
117
102
106
127
119
115
98
104
144
151
132
106
125
122
118
118
2: Get the median, first and third quartiles for the following numbers
7.2
36.6
10.1
7.6
Chapter 1
1.6, 1.9, 1.13, 1.18
Chapter 2
2.7, 2.8,
2.11, 2.14, 2.16
2.28, 2.31, 2.34
2.36, 2.41, 2.50, 2.57, 2.64
2.72, 2.79
2.90, 2.95, 2.97, 2.103
2.114, 2.121
2.124, 2.130, 2.136
7.2
16.4
17.2
16.1
6.7
22.9
Continuous Distributions
Distribution
Uniform
Normal
Exponential
Gamma
Chi-square
Beta
Probability Function
f (y) =
1
; θ ≤ y ≤ θ2
θ2 − θ1 1
#
$
! ”
1
1
2
f (y) = √ exp −
(y
−
µ)
2σ 2
σ 2π
−∞ < y < +∞ f (y) = f (y) = ! $ 1 α−1 −y/β e ; α y %(α)β 0