snowball sampling

Snowball SamplingSnowball sampling is an approach for locating information rich key informats. In this approach few potential respondents are contacted and asked whether they know anybody with the characteristics that you are looking for in your research.

For example, if you wanted to interview a sample of vegitrians, or cyclists or people with a particualar disability, etc your initial contacts may have a knowledge.

Snowball sampling is not a stand-alone tool; the tool is a way of selecting participants and then using other tools, such as interviews or surveys. Having identified those with the skills and/or knowledge or characteristics you require, you would then approach these people to invite them to participate in a community consultation process.

Objectives:

Snowball sampling is designed to identify people with particular knowledge, skills or characteristics that are needed as part of a committee and/or consultative process. Snowball sampling uses recommendations to find people with the specific range of skills that has been determined as being useful, as such, snowball sampling aims to make use of community knowledge about those who have skills or information in particular areas.

Outcomes:

Snowball sampling allows you to identify the resources within a community and to select those people best suited for the needs of a project or process.

Uses/strengths:

Helps to determine stakeholders. Increases the number of participants in process.
Builds on resources of existing networks. Determines stakeholders unknown to you.

Special considerations/weaknesses:

Choice of initial contacts is most important.
Participation process should be drafted prior to the sampling to encourage participation from potential contacts.

http://www.statpac.com/surveys/sampling.htm
http://ccnmtl.columbia.edu/projects/qmss/samp_type.html

Difference between Simple Random Sampling and Convenience Sampling

Simple random sampling

A sampling procedure that assures that each element in the population has an equal chance of being selected is referred to as simple random sampling .

The selection bias is not possible in simple random selection.

In simple random selection the selection of units from the population does not based on easy availability it depends upon random selection.

The result can be generalize as the selection is done randomly.

http://www.nedarc.org/nedarc/collectingData/participantSelection/probabilitySampling/images/stratifiedSample.gif

Eg: An example may make this easier to understand. Imagine you want to carry out a survey of 100 voters in a small town with a population of 1,000 eligible voters. For example, we could write the names of all voters on a piece of paper, put all pieces of paper into a box and draw 100 tickets at random. You shake the box, draw a piece of paper and set it aside, shake again, draw another, set it aside, etc. until we had 100 slips of paper. These 100 form our sample. And this sample would be drawn through a simple random sampling procedure - at each draw, every name in the box had the same probability of being chosen.



Convenience Sampling

A convenience sample chooses the individuals that are easiest to reach or sampling that is done easy.

Convenience sampling does not represent the entire population so it is considered bias.

In convenience sampling, the selection of units from the population is based on easy availability and/or accessibility.

The results can not be generalize , the results are not applicable for all ,We can’t draw any meaningful conclusion from results we obtain.

http://instruct.uwo.ca/fim-lis/504/504sam.gif

Eg : If you want to choose 5 people from a class of 50. You could choose : First 5 students who. raise their hand. First 5 students in the first row. 5 tallest students .
A convenience sample is a sample where the students are selected, at the convenience of the researcher

Art Of Communication

This post is in with reference to your question .......

• put a picture that conveys communication or connection
  write quotes (your own or by great authors! ;)related to connection or communication
  
  Communication:
  "Any act by which one person gives to or receives from another person information about that person's needs, desires, perceptions, knowledge, or affective states. Communication may be intentional or unintentional, may involve conventional or unconventional signals, may take linguistic or nonlinguistic forms, and may occur through spoken or other modes."
  In business and in the workplace, on the domestic front and in our social lives, we all stand to benefit from more effective communication skills. We crave for more fulfilling interpersonal relationships. This site is dedicated to helping you achieve your goals. New features added continually!
  

http://www.unm.edu/~devalenz/handouts/defcomm.html










"The art of communication is the language of leadership."
— James Humes












There is more than a verbal tie between the words common, community, and communication.... Try the experiment of communicating, with fullness and accuracy, some experience to another, especially if it be somewhat complicated, and you will find your own attitude toward your experience changing.




-Jhon Dewey
http://www.museummarketingtips.com/quotes/communication.html


















Words are, of course, the most powerful drug used by mankind.

_Rudyard Kipling











It is the ability to describe others as they see themselves.

- Abraham Lincoln










Speech is power: speech is to persuade, to convert, to compel. It is to bring another out of his bad sense into your good sense.

-Ralph Waldo Emerson

http://www.motivational-inspirational-corner.com/getquote.html?categoryid=12










"To effectively communicate, we must realize that we are all different in the way we perceive the world and use this understanding as a guide to our communication with others.”

-Anthony Robbins quotes

http://www.wisdomquotes.com/cat_communication.html


This post is in with reference to your question .......

• Put up a famous slogan by some Advertising company,
  

Slogan for communication :

KAR LO DUNIYA MUTTHI MAIN

Hello hemangi!!!

Goal Orientation:
The sampling design should be based on the study's goals and objectives .
The picture describe the goal of the research which is achived with the help of objectives, the objectives are the way towards goal. The research should be goal oriented for for achiving that goal the proper objectives must be created.

Measurability :
The sampling design provides the data necessary for analysis . It helps in tabulation of data and to measure the variation in the sample statistically to provide a better handle in determining characteristics of the population at large. It is to understand the probability of sample selection; and to reduce unmeasurable biases through better sample design. According to that picture the person is measuring some thing with the help of tool , it shows that for doing measurment in the research some tool is must, that may be questionair , interview , observation etc. The measurment criteria is used in such way that the result should be access easily.

Practicality :
Practicality is to translating the theoretical selections into instructions for field works.
In other words, "the most theoretically perfect sample selection procedure is worthless if the field instructions are not "simple, clear, practical and complete." means being able to adapt to whatever irregularities occur during the conduct of the survey.The field work is an important part for doing research. The research should be practical in the sense can be easily conducted on human beings.

Economy :
Research objectives are depend on available resources (time, money, etc.).
It refers to the cost- effectiveness of the survey infulfilling the research objectives concerning the fulfillment of survey objectives with minimum cost and effort and maximum output. The picture tells us about how much money the research is needed, how much time the research will take and how much the effort the researcher have to do for this research means the effort is worth for that research or not. The research should be done by considering all the expenses such as money , time means the research should not be time taking and also not very difficult for the researcher.

Examples

hello hemangi!

I am writting these examples but i dont know wether they are correct or not:

1) If a researcher want to do research on the students suicide cases in any reputed college, the access may be deneid because it will make a big question mark on college reputation , and also it disclose the many secrets of that college.

2) If researcher want to take interview of any politician may be that person would not be able to spend time for that interview, and the another possiblity is that he/she may not tell all the truth to researcher.

3) If researcher want to conduct research on the successfull businessmen, the access may be deneid because he/she may not like to disclose the secret of his/her success in that bussiness .