probability and Non-probability sampling

Non-probability sampling

1. Non-probability sampling Non-probability sampling is sampling method in which the researcher selects a sample based on the subjective judgmental of the researcher than random selection. In non-probability sampling each unit in your target population does not have equal chance of being included or being selected. This type of sampling is commonly used in a situation where its difficult to use random method.

2. Convenience sampling Convenience sampling is non-probability sampling techniques where samples are selected from population because its easily to recruit for the researcher and the researcher didn’t consider selecting a sample representing the whole population. Example: you are investing the population of people who like playing football and basketball, and you ask people online to choose the game they like to play. At that time, you will get the people online only without considering those who did not have access to internet. most of the time convenience sampling is used because it helps to collect data easily and quickly and its cost effectiveness.

3. Quota sampling quota sampling is a non-probability method that relies on the non-random selection of predetermined number or proportion unit .in quota sampling method individuals are selected based on specific criteria such as age, gender, income, education level, height until the desired sample is reached. examples A researcher wants to conduct a survey on the opinions of voters in a city, they may divide the population into subgroups based on age and gender. They may then select a certain number of individuals from each subgroup to ensure that their sample is representative of the entire population.

4. Quota sampling is divided into 2 types Proportional quota sampling Proportional quota sampling s used when the size of the population is known. This allows you to determine the quota of individuals that you need to include in your sample in order to be representative of your population 2. Non proportional quota sampling Non proportional quota sampling is used when the size of the population is unknown. Here, it’s up to you to determine the quota of individuals that you are going to include in your sample in advance. Example: Let’s say you are seeking opinions about the design choices on a website, but do not know how many people use it. You may decide to draw a sample of 100 people, including a quota of 50 people under 40 and a quota of 50 people over 40. This way, you get the perspective of both age groups.

5. JUDGEMENTAL SAMPLING In judgmental sampling the researcher selects purely on the researcher’s knowledge and credibility, researcher choose those people who fit to participate in research study. The process of selecting a sample using judgmental sampling involves the researchers carefully picking and choosing each individual to be a part of the sample. The researcher’s knowledge is primary in this sampling process as the members of the sample are not randomly chosen. Examples An example of judgmental sampling in action might be a study on job satisfaction among employees at a particular company. The researcher may choose to select employees who have been with the company for a certain number of years or who hold specific job titles that are most relevant to the research question. Judgmental sampling is also known as purposive sampling

6. Snow ball sampling Snow ball sampling is non probability technique which help the researchers to find the sample when its difficult to locate. Is used when the population you want to survey is hard to reach, or there is no other sampling frame to help. Examples Obtaining samples of populations at risk for HIV Studying illegal drug users over the age of 40   

7. Advantages of non probability sampling Advantages It’s quick and cheap to carry out. You only need to invest a small amount of time to gather a sample size you feel is appropriate before you begin your research. It can be a quick starting point to investigate or explore if there is an issue among a specific audience group or target market, leading to more investment or further research opportunities. Its not expensive by using non probability sampling it does not require a researcher to have large amount of money for the research

8. Disadvantages  the sample size is unclear. You may find you need more participants or less at a later stage, which could waste time and money. In some methods, such as convenience sampling, samples can be filled with people who are more likely to agree to want to be part of research because they hold strong views that they want to share. This can skew the validity of the results.

9. So u rces What Is Non-Probability Sampling? | Types & Examples (scribbr.com) Non-Probability Sampling: Types, Examples, & Advantages | QuestionPro What is Non-Probability Sampling in 2023? - Qualtrics