Spring 2008 Probability and Statistics (MATH/STAT 352) 3 credits William J. Raggio Building (WRB) Room 2003 TR 1:00-2:15 PM
Instructor: Ilya Zaliapin Office: Ansari Business Bldg., Room 609 Office hours: TR 11:00-noon + 4:00-5:00PM + by appt Phone: (775)
(census, polls, questionnaire, elections, physical experiments, etc.)
(summarize, visualize, construct models )
(tell what is happening now and what may happen in the future )
Data from MATH/STAT 352, Spring 2007 (73 people)
Data from MATH/STAT 352, Sprin
The probability theory begins in attempts to describe gambling (how to win, how to divide the stakes, etc.), probability theory mainly considered discrete events, and its methods were mainly combinatorial
Gerolamo Cardano (September 24, 1501 September 21,
Random variable (rv) central concept of probability theory
RV = Numerical description of experiment
Sample space S
Definition: A random variable X is a function whose domain is the sample space and range is the real line.
Outcome
x
Experiment: tossing a d
Radar target detection
How reliable is the signal on the screen? (Is it a target or a false alarm?)
Medical screening
How reliable is the positive test? (Is it a disease or a false alarm?)
How does probability help to answer such questions?
Deck of playin
spread, most of the observed values
x0 is the central value, characteristic value
Measurement
1
0
1
Measurement
1
0
1
Measurement
1
0
1
Measurement
1
0
1
Measurement
Data from "Smart Student" Questionnaire
Mean = 20 Median = 14
Outlier
N=65, Sample mean =
Homework Solutions Homework #3
Section 2.1
2. (a) S=cfw_1, 2, 3, 4 or S=cfw_1,1,2,2,2,3,3,4 (second is more convenient for probability computations) (b) P(even number)=P(2) + P(4) = 3/8 + 1/8 = 1/2 (c) No, the set of possible outcomes is still cfw_1, 2, 3
Home Work 5 1. Section 2.3: 23 Electrical circuit boards are rated excellent, acceptable, or unacceptable. Suppose that 30% of boards are excellent, 60% are acceptable, and 10% are unacceptable. Further, suppose that 10% of excellent boards fail, 20% of a
Homework Solutions Homework #2
Section 1.2
Section 1.3
6. (a) The histogram should be skewed to the right. Here is an example.
(b) The histogram should be skewed to the left. Here is an example.
(c) The histogram should be approximately symmetric. Here is