I have to sample 300 persons. How do I go about doing this and how do I know that the population I have chosen has the characteristics that I am looking for?
The population is the group you want to gain information about. The sample is the 300 persons, a portion of that population.
What population concerns you? Children? Adults? College students? NFL players? Politicians? Nurses?
What do you want to find out about this population?
How are you sampling them? Written questionnaires mailed or given in person? Blood samples? Behavioral samples?
Regardless of the population, the sample needs to be random — or representative of the population.
Once you have defined what you are studying, you might want to repost your question.
I hope this helps. Thanks for asking.
To sample 300 persons and ensure that the population you have chosen has the desired characteristics, you can follow these steps:
1. Define your research objective: Clearly establish the specific characteristics you are looking for in the population. This could be age, gender, occupation, location, etc.
2. Determine the sampling method: There are different sampling methods you can use, such as random sampling, stratified sampling, or cluster sampling. The choice of sampling method depends on the nature of your study and the population you wish to sample. Random sampling involves giving each person in the population an equal chance of being selected, while stratified sampling involves dividing the population into subgroups (strata) and then randomly selecting individuals from each stratum.
3. Define your population: Clearly define the population you wish to sample from. This could be a specific geographic area, a particular age group, or any other relevant criteria. Make sure your population accurately represents the target population of interest.
4. Determine the sample size: Calculate the appropriate sample size based on the desired level of confidence, margin of error, and population size. If you're unsure about how to determine the sample size, you may seek assistance from a statistician or use sample size calculators available online.
5. Choose your sampling frame: A sampling frame is a list of individuals from which the sample will be selected. Ensuring that your sampling frame is comprehensive and representative of the population is essential for obtaining accurate results.
6. Select your sample: Use the chosen sampling method to select your sample of 300 individuals. For example, if you opt for random sampling, you can assign a unique number to each individual in the sampling frame and use a random number generator to select the sample.
7. Assess the characteristics of the sample: Once the sample is selected, evaluate whether the sampled individuals possess the desired characteristics. Compare the characteristics of the sample to the defined research objectives to determine if they align.
It's important to note that there is always a possibility of sampling error, where the sample may not perfectly represent the population. However, by following appropriate sampling methods and techniques, you can minimize sampling bias and improve the chances of selecting a representative sample.