Chapter 8 Estimation of the mean and proportion Confidence Intervals.
8.2 Estimation of a population mean : known .
Always check assumptions first
Case I. If the following three conditions are fulfilled:
1. Random sample
2. The population standard deviati
Chapter 3.1, 3.2
Numerical descriptive measures
Graphs provide a global/qualitative description of
a sample, but they are imprecise for use in
statistical inferences.
We use numerical measures which can be
calculated for either a sample (these measures
ar
Homework 2 deadline Thursday, Feb 18 (I will collect in class, but if you are ready , you can bring to your TA in discussions)
Problem 1.The five-number summary of credit hours for 24 students in a statistics class is:
From this information, we know that
Final EXAM review
It covers : Exam 1 - correlation and linear regression
Exam 2 ( I will skip Chapter 4)
Chapter 8. Confidence Intervals for the population mean (use z and t)and proportion ,
minimum sample size
Chapter 9.1 - 9.4 hypothesis tests about the
Final EXAM — review
It covers : Exam 1 ‘- correlation and linear regression
Exam 2 - normal , binomial distribution, expected value of a random variable
Chapter 8‘ s r : ' * Conﬁdence Intervals for the population mean and proportion ,
k 7_ minimum sample
Homework 2
3.102 . The following data represent the credit scores of 22 randomly selected loan applicants.
494
728
468
533
747
639
430
690
604
422
356
805
749
600
797
702
628
625
617
647
772
572
Prepare a box-and-whisker plot. Are these data skewed in any
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Stat 240.
Worksheet 3 Wednesday
1. Medical researchers enlisted 90 subjects for an experiment comparing treatments for depression. The subjects were
randomly divided into three groups and given pills to take for a period of three months. Unknown to them,
3.4 USE OF STANDARD DEVIATION
Empirical Rule
For a bell shaped distribution approximately
1. 68% of the observations lie within one standard
deviation of the mean
2. 95% of the observations lie within two standard
deviations of the mean
3. 99.7% of the ob
Stat 240.
Worksheet 3 Monday
1. The following are a sample of test scores from a 100-point test: 61, 50, 100, 85, 15 ,65, 75, 70 , and 90.
(a ) Construct a box-plot to display the data
(b) describe the distribution (shape, outliers)
2. Medical researchers
Chapter 3.1 and 3.2
Numerical descriptive measures
Graphs provide a global/qualitative description of a
sample, but they are imprecise for use in statistical
inferences.
We use numerical measures which can be calculated
for either a sample (these measures
Chapter 1.
1.1.What is statistics?
The field of statistics is evolving and growing in
ways few imagined even 15 years ago.
The field of statistics has been around for
centuries, yet its significance to society and the
economy is possibly greater today tha
Chapter 2.
Organizing and graphing data.
Graphing data is the first and often most
important step in data analysis
The following handout discuss common graphs
for qualitative and quantitative variables.
1
Example 1
In 1969 the war in Vietnam was at its he
Chapter 4. Probability
Remember the objective:
Population
Probability
Probability
Sample
Describe the
sample data
Compute measures of
variability
1
1. Probability and statistics are both related to a sample
and a population.
2. Probability: certain prope
COUNTING RULE
Counting Rule to Find Total Outcomes
If an experiment consists of three steps and if the first step can
result in m outcomes, the second step in n outcomes, and the
third in k outcomes, then
Total outcomes for the experiment = m n k
Examp
Chapter 5.1-5.3
THE RANDOM VARIABLES AND THEIR
PROBABILITY DISTRIBUTIONS
Each year, the Centers for Disease Control and
Prevention recommend a flu shot for certain groups
of people who are classified as at risk for serious
complications from the most comm
Chapter 9.2 l-lypotltesis tests about It: a known
Case I. If the following three conditions are fulfilled:
I. The population standard deviation 6 ist known
2. The sample size is small (i.e. a < 30)
3. The )OpllltlllOIt from which the sample is selected is
Take Home Exam IV:
R exam over Chapters VIII, XI
1. ( 5 pts.) Suppose your data sample consists of the following scores on a history
exam:
Scores = c(28, 40,21, 26, 17 ,27, 21, 28, 36, 34, 22, 29, 40, 27, 41, 35, 33, 34, 32, 32)
You know that the populati
Bivariate Data part 1 (both variables are
categorical)
Example : Data were collected to measure the effect of
the body weight on the blood pressure in individuals
aged between 15 and 30.
Sample unit: individual aged between 15 and 30.
Variables measured i
3)
A data set on money spent on lottery tickets during the past year by 200
households has a lowest value of $1 and a highest value of $2680.
Suppose we want to group these data into 6 classes of equal widths.
Assuming we take the lower limit of the first
Workshhet 3 (chapter 3)
Stat 240
Activity 1. Define each of the following (give a definition or an equation to calculate and/or an example)
Name
Definition or an equation
to calculate or an example
Where do we use it ? Why
it is important ?
Measures of ce
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injuries that
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. "BEPARTMEENT OF MATHEMATICS AND STATISTICS
UMVERSITY OF MASSACHUSETTS
Stat 240 EXAM 1 October 13, 2016
NAME:
19ng .
\
Discussion session (name of your TA):
hto Talking during the exam.
Turn off! put away all cell phones.
Only the exam sheet is allowed
Exam 2 practice exam solution
Question 1
Question 2
more extreme than yours.
Question 3
Question 4
Question 5
Question 9
I believe the population mean is lower than 69 inches, otherwise it would be difficult to find a sample with average 66.
Question 10
I
Group Names:
Sam Asamoah (Hachem), Kevin Boino (Nguyen), Steve Ravazzoli (Wu Mengyuan),
Ryan Saul (Hachem)
Topic:
Number of hours a person spends on their phone per day
Method:
Estimation of population a mean
Cellphones have seemingly become a necessity f
To download Minitab - 30-day free trial - go to:
http:/www.onthehub.com/minitab/
If you are Mac user , you have to choose Minitab Express , if you are Window user - Minitab 17
is a better choice.
Lab 1 Minitab .
Refer to the data: Blood Pressure for men a