A. Identify the population and variables.
Population is the whole group of Richmond buyers interested to buy a house. Variables are: location, price, bedrooms, bathrooms, sq.ft, and realtor

B. Identify variables as categorical or quantitative.
* Location is categorical variable
* Price is quantitative variable
* Bedrooms are quantitative variable
* Baths are quantitative variable
* Sq.Ft is quantitative variable
* Realtor is categorical variable

C. What are some possible population parameters of interest? The parameter in this case is the 182 listing in Richmond, some other options to be considered are: average house price ($310,381), house size, how many bedrooms and bathrooms, location of the house, who is it listed by and the city zone.

D. What are some possible sample statistics that could be calculated from this data? It is not necessary to calculate the statistics, just identify them. Average price for houses based on the county location, average household income, preferable characteristic and taste of the house buyers

E. What is the sampling frame for the sample?
The sampling frame is randomly selected from the single-dwelling properties for sale in the Greater Richmond area shown on the website realestate.aol.com.

F. What is the sampling design?
Systematic Random sampling (SRS)

G. Are there any sources of bias in the sample?
Yes – based on the data we have the direction of the bias source is over charged.
H. If we had decided to use a Stratified Sampling design, what would be appropriate strata?

We can collect the sample by the process of dividing houses of the population in Richmond area into homogeneous subgroups before sampling then select a random selection within each stratum then combine the result.

I. Are there other factors not shown in the data set that may affect the price of a house?

...UNIVERSITY OF NAIROBI
COLLEGE OF EDUCATION AND EXTERNAL STUDIES
SCHOOL OF CONTINUING AND DISTANCE EDUCATION
DEPARTMENT OF EXTRA-MURAL STUDIES.
LDP603: RESEARCH METHODS GROUP ASSIGNMENT
GROUP 5 QUESTION: DISCUSS THE VARIOUS PROBABILITY AND NON-PROBABILITY SAMPLING TECHNIQUES USED IN RESEARCH.
GROUP 5 (A) MEMBERS
|S/NO |SURNAME |OTHER NAMES |REG. NO |SIGNATURE |
| |GICHOHI |BENARD MUTAHI |L50/64207/2010 | |
| |AYUYA |ANDREW ANGAYA |L50/64684/2010 | |
| |WAHINYA |COSMUS KIRORI |L50/63829/2010 | |
| |OSUMBAH |LILIAN ACHIENG’ |L50/64090/2010 | |
| |CHEBOI |ANDREW KIMUTAI |L50/64237/2010 | |
| |OGUDI |PETER ONYANGO |L50/63654/2010 | |
| |NJAU |JOSEPH NJENGA |L50/65416/2010...

...SAMPLING AND ITS CHARACTERISTICS
INTRODUCTION:
For studying any problem it is impossible to study the entire population. It is therefore convenient to pick out a sample out of the population proposed to be covered by the study. Sampling method is an important tool in the realm of social science researches. It was first introduced and used in social research in 1754 A.D. by Bowley.
DEFINITION:
“A sample is finite part of a statistical population whose properties are studied to gain information about the whole.” – Webster Dictionary, 1985
“a smaller representation of large whole.” – Goode and Hatt
‘a subject of cases from the population chosen to represent it.” – Nan Lin
“Sampling method is the process or the method of drawing a definite number of the individuals, cases or the observations from a particular universe, selecting part of a total group for investigation.” – Mildred Parton
Therefore, Sampling can be defined as the method, or the act, process, or technique of selecting a suitable sample, or a representative part of a population for the purpose of determining parameters or characteristics of the whole population. For this, population is divided into a number of parts called Sampling Units.
Or, we can say, that when a small group is selected as representative of the whole it is known as sample.
Or, a sample size is a small percentage of a population that is used for statistical...

...Statistical Sampling for Testing Control Procedures
1. Statistical Sampling for Testing Control Procedures
2. MULTIPLE CHOICE
3. 1. Auditors who prefer statistical sampling to non-statistical sampling may do so
because statistical sampling helps the auditor
4. a. Measure the sufficiency of the evidential matter obtained. b. Eliminate
subjectivity in the evaluation of sampling results. c. Reduce the level of tolerable
error to a relatively low amount. d. Minimize the failure to detect a material
misstatement due to non-sampling risk.
5. ANSWER: B
6. 2. If all other factors in a sampling plan are held constant, changing the measure
of tolerable error to a smaller value would cause the sample size to be:
7. a. Smaller. b. Larger. c. Unchanged. d. Indeterminate.
8. ANSWER: B
9. 3. Which of the following sampling plans would be designed to estimate a
numerical measurement of a population, such as a dollar value?
10. a. Numerical sampling. b. Discovery sampling. c. Sampling for attributes. d.
Sampling for variables.
11. ANSWER: D
12. 4. Based on a random sample, it is estimated that four percent, plus or minus two
percent, of a firm's invoices contain errors. The plus or minus two percent is
known as the estimate's:
13. a. Precision. b. Accuracy. c. Confidence level. d. Standard error.
14. ANSWER: A...

...CONVENIENCE SAMPLING
Convenience Sampling:
Convenience sampling refers to the non probability process by which a scientist gathers statistical data from the population. This form of selection is done based on the ease of gaining the statistical data. Rather than gathering a more accurate array of data from the population, the researcher simply gathers data from people nearby. A researcher might go to a nearby mall, or street corner to gather data. This form of data collection works for some areas of study, but researcher bias may result in inaccurate data.
Convenience Sampling:
Convenience sampling is a type of non-probability sampling technique. Non-probability sampling focuses on sampling techniques that are based on the judgment of the researcher.
Convenience Sampling:
A statistical method of drawing representative data by selecting people because of the ease of their volunteering or selecting units because of their availability or easy access. The advantages of this type of sampling are the availability and the quickness with which data can be gathered. The disadvantages are the risk that the sample might not represent the population as a whole, and it might be biased by volunteers.
Convenience Sampling:
It is a sampling method in which units are selected based on easy access/availability....

...
Statistical Sampling
Statistical Sampling
1. The authors of the paper make assumptions about the U.S. population on three dimensions. What are the three dimensions? (Hint: The authors refer to these dimensions as "components of change.")
Answer: The three dimensions would be migration, fertility, and mortality.
2. What is the expected population of the U.S. in 2050 given the new series (i.e., based on 1998 data) based on the lowest series? The middle series? And the highest series?
Answer: Lowest - 313,546,000
Middle - 403,687,000
Highest - 552,757,000
3. What do the lowest, middle, and highest series represent?
Answer: Just as one would utilize sampling in an audit context, this document emphasizes how key sampling judgments affect sample results. The lowest, middle, and highest series represent the effects of varying expectations in regards to mortality fertility, and migration. These projections don’t include a systematic measurement of uncertainty regarding these dimensions. By applying variant assumptions for each component in an individual manner, this would result in the range of a population series that would be identified with the maximum variance to this component. In order to produce the lowest and highest series, the authors combined the extreme values of all three major components favored the lowest and highest population growth easily. This means the extreme...

...UNITED NATIONS SECRETARIAT Statistics Division
ESA/STAT/AC.93/3 03 November 2003
English only Expert Group Meeting to Review the Draft Handbook on Designing of Household Sample Surveys 3-5 December 2003
DRAFT
Sampling frames and master samples *
by Anthony G. Turner
**
* **
This document is being issued without formal editing. The views expressed in this paper are those of the author and do not imply the expression of any opinion on the part of the United Nations Secretariat.
Table of contents
Chapter Three: Sampling frames and master samples ...................................................................3 A. Sampling frames and their development ..............................................................................3 3.1. Definition of sample frame ..............................................................................................3 3.1.1. Sample frame and target population ........................................................................3 3.2. Properties of sampling frames..........................................................................................4 3.2.1. Completeness ...........................................................................................................4 3.2.2. Accuracy ..................................................................................................................5 3.2.3. Current frame...

...to Customer Satisfaction Surveys
Background The Washington Suburban Sanitary Commission (the Commission or WSSC) is a bi-county agency in Maryland established to provide water supply and wastewater treatment services for approximately 1.7 million people in Montgomery and Prince George's Counties. WSSC has a service area of almost 1,000 square miles, and serves about 430,000 accounts. Ascellon’s work on this project was guided by three critical objectives that are tied to our customer’s strategic initiatives: 1. To stay attuned to what customers truly value, their desired services and service levels; 2. To provide those services in a world-class manner; and 3. To improve relations with the customer base. Identifying and Segmenting the Population: Ascellon identified the various segments of stakeholders for WSSC, namely: the elected officials and regulating agencies (stakeholders) WSSC must be accountable to; and the 1.6 million consumers of WSSC’s end products: drinking water and sewer service. The second segment was further divide into three subsegments: Residential Rate Payers, Commercial Rate Payers, and Service Receivers. By identifying unique segments of our population early in the process, we were able to use the information to design unique survey instruments and sampling plan to improve the reliability of the entire survey. A second, equally important benefit of knowing the audience well is the ability to...

...HealthSouth Shareholders for $109 million. If the case would go to court, E&Y’s first defense should be that they performed their work in accordance with professional standards. They also should be able to claim HealthSouth contributed to, and was the primary cause, of any damages it incurred. In the securities suit, they should only have to show that plaintiffs’claims of Scienter are untrue. 4. HealthSouth concealed the fraud by keeping the fraudulent transactions below $5,000. What recommendation would you have to Ernst & Young to improve its sampling practices? Variables sampling should include a sample of smaller items as well as large items to ensure that there aren’t a sufficient number of errors in the small items that accumulate to a material misstatement. Classical variables sampling and non-statistical sampling (properly performed) should provide a representative sample of large and small items. E&Y used a stratified sampling technique, but it was not representative of the population....