Statistics
Week 8
Estimating the Mean
The Sampling Distribution


If X is normally distributed with a mean of and a standard deviation of , then
for a sample of size n , the distribution of the sample mean (called the sampling
distribution) is also norm
Week 3
Probability
Experiments, Outcomes, and Events

Experiment
o Procedure that may have multiple possible outcomes
o I draw two cards from a deck

Outcomes
o All possible results of the experiment
o I draw the king of spades

Event
o Group of outcom
Week 2
Descriptive Statistics Continued
Measures of Central Tendency

Mean
o Add up all the data and divide by however many numbers there are

Median
o Find the middle value

Mode
o The most common value
Skewed

Data is skewed when mean and median won
Statistics
Descriptive Statistics
Descriptive vs. Inferential Statistics

Descriptive Statistics
o Describe, display and summarize data that you already have

Inferential Statistics
o Use data you do have to make educated guesses about data you dont hav
STAT 2112
Assignment#2
Fall 2015
STAT 2112
Prof.: Tan Le
Student Name: Farihah Chowdhury
Student ID: 823130687
ASSIGNMENT #2
1.
a.
Let X1 be the amount of Ore 1 to be used.
Let X2 be the amount of Ore 2 to be used.
Let X3 be the amount of Ore 3 to be us
(WK/l
/ KC/ STAT 502
Quiz #4
_ 7 c?
Student Name: EMA/WV
Student Number: 9522 511 '7 550
1. The employees of a large international company would like to have a dental plan as part of
their benefits package. The question is: How much does a typica
32/3?
Quiz #1
Student Name: I U A
Student Number:
A survey of families in a particular neighbourhood showed the number of children in each
household:
0 3 4 7 1 2 2
o 1 2 .1 3 H 7
Find the
a. mean _
__. L/
X: O~+l+Q+2+3+ 17
. 7
3 #59 w, 27/.
Problem 1: A meatprocessing company in Alberta produces and markets a package of eight
small sausage sandwiches. The product is nationally distributed, and the company is interested in
knowing the average retail price charged for this item in stores acro
STAT 502
MIDTERM REVIEW
QUESTIONS (SOLUTIONS)
1. For the following sample
3.6
5.9
4.0
7.1
8.2
7.1
7.1
8.0
a. Find the mean, median, and mode.
Solution: The sample mean is equal to
x 3.6 5.9 8.0 / 8 6.375 6.4 .
To find the median, we first arrange the days
Problem 1.
It is known that 35% of Humber students take Statistics. If a student took and passed Statistics course,
there is 94% chance of finding a job within 6 months. If a student did not take any Statistics course, the
chance is 72%. If a randomly sel
Problem 1.
Suppose the following data represents total revenues (in $ millions) for a Canadian company.
Year
Revenue
3Year Moving
Average
Weighted Moving
Average
Exponentially Smoothed
Value with 0.25
2007
4.7
4.70
2008
4.9
4.70
2009
5.4
4.75
2010
5.1
20
STAT 502 FINAL EXAM REVIEW QUESTIONS
SOLUTIONS
1.
In a study relating the amounts of time required for roomservice delivery at a newly opened
Humber Radisson Hotel, 20 deliveries had a mean time of 24.2 min and a standard deviation of 8.7
min. The sample
FORMULAE & TABLES FOR STAT 502 FINAL EXAM
p opulation mean, p opulationstandard deviation
n
x sample mean ; x
x
i
i 1
, where n sample size
n
n
s sample standard deviation; s
x
i 1
i
x
2
n 1
df number of degrees of freedom
Probability: Pevent
T he n
STAT*2060DE W12
Questions for Assignment #1
Assignment #1 will be a D2L quiz, with a deadline of Thursday January 19 at 11:59 pm. The questions
on the quiz will be the same as those given here. Read the document Intro to quizzes for
STAT*2060DE" on D2L fo
Following is a selection of titles of a few essays submitted for Econ3720 and Econ3730 in recent years. The information value of the titles varies a lot, as you see. I am not saying that any particular essay was a good one, or that it remains a good essay