3.5 Sample Size
Section 3.5
Sample Size
How many samples
should you take?
Too many
wasted
money
Too few
inaccurate
conclusions
1
3.5 Sample Size
CHOOSING AN APPROPRIATE SAMPLE SIZE
DEPENDS ON 3 FACTORS
1. DESIRED LEVEL OF CONFIDENCE
- 95% and 99% most com
Time spent on the internet per week follows a normal distribution with an average 13.5
hours per week and a standard deviation of 5.6 hours.
a) Can we assume a normal distribution of sample means?
b) What is the probability of a sample mean of 15 values b
Time spent on the internet per week follows a normal distribution with an average 13.5
hours per week and a standard deviation of 5.6 hours.
a) Can we assume a normal distribution of sample means?
b) What is the probability of a sample mean of 15 values b
In a recent survey of 200 people who taste tested a new kind cereal, 46 people said they would purchase it.
The manufacturer thought it would be worth while launching the new cereal if more than 20% of the
population would consider purchasing it.
a) Can w
In a recent survey of 200 people who taste tested a new kind cereal, 46 people said they would purchase it.
The manufacturer thought it would be worth while launching the new cereal if more than 20% of the
population would consider purchasing it.
a) Can w
Historically at Jamestown Steel Co. daily production of desks follows a normal
distribution with a mean of 200 and standard deviation of 16. A new production
method was recently introduced, and the company would like to know if there has
been a change in
Historically at Jamestown Steel Co. daily production of desks follows a normal
distribution with a mean of 200 and standard deviation of 16. A new production
method was recently introduced, and the company would like to know if there has
been a change in
Historically at Jamestown Steel Co. daily production of desks follows a normal
distribution with a mean of 200 and standard deviation of 16. A new production
method was recently introduced, and the company would like to know if there has
been a change in
A recent article in a magazine reported that a job awaits only 1 in 3 new college
graduates across Canada. A random sample of 200 recent Fanshawe
graduates revealed that 80 had jobs. At the .02 significance level, can we
conclude that Fanshawe has a large
A recent article in a magazine reported that a job awaits only 1 in 3 new college
graduates across Canada. A random sample of 200 recent Fanshawe
graduates revealed that 80 had jobs. At the .02 significance level, can we
conclude that Fanshawe has a large
In order to estimate the mean amount spent by all costumers, a retail chain surveyed
400 random purchases. The sample showed a mean purchase amount of $500 and a
standard deviation of $100. Establish a 99% confidence interval estimate of the mean
amount p
In order to estimate the mean amount spent by all costumers, a retail chain surveyed
400 random purchases. The sample showed a mean purchase amount of $500 and a
standard deviation of $100. Establish a 99% confidence interval estimate of the mean
amount p
A Survey of 700 consumers shows that 500 purchase sugar-free gum regularly.
Contstruct a 95% confidence interval for the population proportion of customers who
regularly purchase sugar-free gum.
= 0.05
p = ( #
,
#
)
n = 700
x = 500
p-hat = 0.7142857
z =
A Survey of 700 consumers shows that 500 purchase sugar-free gum regularly.
Contstruct a 95% confidence interval for the population proportion of customers who
regularly purchase sugar-free gum.
=
p=(
,
)
A market survey was conducted to estimate the prop
A study is set up to determine the average remuneration earned by members of city council
in large cities. It is desired that the error from the mean is less than $5,000 with a 95% level
of confidence. It is estimated the least a council member is paid is
A study is set up to determine the average remuneration earned by members of city council
in large cities. It is desired that the error from the mean is less than $5,000 with a 95% level
of confidence. It is estimated the least a council member is paid is
1.1 Sampling Methods
Section 1.1
Sampling Methods
STATISTICS
1
1.1 Sampling Methods
TYPE OF STATISTICS
DESCRIPTIVE
INFERENTIAL
Methods of organizing,
summarizing, and
presenting data in an
informative way.
Methods are used to
estimate the characteristics
1.1 Sampling Methods
Section 1.1
Sampling Methods
STATISTICS
The science of collecting,
organizing, presenting,
analyzing, and interpreting data
to assist in making more
effective decisions
1
1.1 Sampling Methods
TYPE OF STATISTICS
DESCRIPTIVE
INFERENTIAL
Consider a plant with a very large number of workers. The plant has a mean age
of 50 years, with a standard deviation of 4 years.
a) What is the z-score of a worker who is 57 years of age?
b) What percentage of workers are less than 57 years old?
c) What
Consider a plant with a very large number of workers. The plant has a mean
age of 50 years, with a standard deviation of 4 years.
a) What is the z-score of a worker who is 57 years of age?
b) What percentage of workers are less than 57 years old?
c) What
CONFIDENCE INTERVALS & SAMPLE SIZE
1.
2.
3.
4.
5.
6.
7.
8.
The owner of Brittens Egg Farm wants to estimate the mean number of eggs
laid per chicken. A sample of 20 chickens shows they laid an average of 20
eggs per month with standard deviation of 2 eggs
The following is a list of Tim Horton's Locations in London, Ontario. In order to gain
information on customer satisfaction with drive thru service, customers will be surveyed at 7
randomly selected locations. Choose which 7 stores will be selected by mea
The following is a list of Tim Horton's Locations in London, Ontario. In order to gain
information on customer satisfaction with drive thru service, customers will be surveyed at 7
randomly selected locations. Choose which 7 stores will be selected by mea
Create a HISTOGRAM for the following example:
The Wachesaw Outpatient Centre, designed for same-day minor surgery,
opened last month. Following is the number of patients served for the
first 10 days:
23
20
32
MAX = 32
MIN = 18
Class width = 4.427189
5
Bin
Create a HISTOGRAM for the following example:
The Wachesaw Outpatient Centre, designed for same-day minor surgery,
opened last month. Following is the number of patients served for the
first 10 days:
23
20
32
31
18
28
29
25
22
29
Create a HISTOGRAM for th
The following data is from a quality assurance check on filling levels of 591mL
bottles at Coca-Cola. Find the MEAN, MEDIAN, and MODE for the data.
591.33
591.68
590.53
590.87
590.75
590.31
590.73
591.44
590.90
590.39
591.67
591.13
591.04
591.19
590.36
59
The following data is from a quality assurance check on filling levels of 591mL
bottles at Coca-Cola. Find the MEAN, MEDIAN, and MODE for the data.
591.33
591.68
590.53
590.87
590.75
590.31
590.73
591.44
590.90
590.39
591.67
591.13
591.04
591.19
590.36
59
The following data is from a quality assurance check on filling levels of 591mL
bottles at Coca-Cola. Find the STANDARD DEVIATION, VARIANCE, and
INTERQUARTILE RANGE for the data.
591.33
591.68
590.53
590.87
590.75
590.31
590.73
591.44
590.90
590.39
591.67
The following data is from a quality assurance check on filling levels of 591mL
bottles at Coca-Cola. Find the STANDARD DEVIATION, VARIANCE, and
INTERQUARTILE RANGE for the data.
591.33
591.68
590.53
590.87
590.75
590.31
590.73
591.44
590.90
590.39
591.67
REQUIRED READINGS AND EXERCISES SUMMER 2016
CHAPTER 3 INCOME OR LOSS FROM AN OFFICE OR EMPLOYMENT PART 2
For each exercise and problem you do, please check the solutions in the Study Guide
Inclusions Allowances
- Read paragraph 3-125 to 3-137
- Do Exercis
REQUIRED READINGS AND EXERCISES SUMMER 2016
For each exercise and problem you do, please check the solutions in the Study Guide
CHAPTER 8 CAPITAL GAINS AND CAPITAL LOSSES
Economic Background
- Read paragraphs 8-1 to 8-10
General Rules
- Read paragraphs 8-
REQUIRED READINGS AND EXERCISES SUMMER 2016
CHAPTER 2 PROCEDURES AND ADMINISTRATION
For each exercise and problem you do, please check the solutions in the Study Guide
Administration Of The Department
- Read paragraph 2-3 to 2-7
Returns And Payments - Ind
REQUIRED READINGS AND EXERCISES SUMMER 2016
CHAPTER 7 INCOME FROM PROPERTY
For each exercise and problem you do, please check the solutions in the Study Guide
Property Income: General Concept
- Read paragraphs 7-2 to 7-5
Interest Income
- Read paragraphs
REQUIRED READINGS AND EXERCISES SUMMER 2016
CHAPTER 3 INCOME OR LOSS FROM AN OFFICE OR EMPLOYMENT PART 1
For each exercise and problem you do, please check the solutions in the Study Guide
Employment Income Defined
- Read paragraph 3-1 to 3-11
- Do Exerci