Census & Sample Surveys

 Definition :

 A census involves collecting data from every individual or item in a population, while a sample survey involves collecting data from a smaller subset of the population. Census is useful for small populations or when accuracy is crucial, while sampling is useful for large populations or when time and cost constraints exist.

Data collection is a fundamental step in statistical analysis, and the choice of data collection method should be based on the specific research question and the characteristics of the population being studied. Understanding the different data collection methods and their strengths and weaknesses can help researchers choose the most appropriate method for their study, ensuring that the data collected is accurate, reliable, and relevant to the research question.

Methods :

• Census Sampling
• Sampling Method

Census Sampling: Census sampling is a method of data collection used in quantitative techniques for business. It involves collecting data from the entire population, rather than just a sample. This can be useful in situations where the population is small, and it is feasible to collect data from every individual or entity.

However, census sampling can also be time-consuming, expensive, and impractical when dealing with large populations. In these cases, sampling methods may be used to collect data from a smaller subset of the population, which can then be used to make inferences about the larger population.

The government of India conducts a census every ten years to collect information from all households in the country. The census includes details on income, earning members, children, and family members. This method ensures that no household is left out, and the collected data provides valuable demographic information, such as birth rates, death rates, total population, and population growth rate of the country. The last census was conducted in 2011 and the next one is due in 2021. The census helps the government in decision-making and planning for the future, as well as providing useful information for researchers and businesses. 

Overall, the census is an essential tool for understanding the population and its characteristics in India.

Sampling Method: Sampling is an important technique in quantitative research for businesses. It is the process of selecting a representative sample from a larger population for the purpose of collecting data and making inferences about the population.

There are different sampling methods that can be used in quantitative research, including:

• Simple Random Sampling: This method involves selecting a sample randomly from the population, where every individual in the population has an equal chance of being selected.
• Cluster Sampling: This method involves dividing the population into clusters and then selecting a random sample of clusters. Data is collected from all individuals within the selected clusters.
• Systematic Sampling: This method involves selecting a random starting point from the population and then selecting every nth individual from the population until the desired sample size is reached.
• Convenience Sampling: This method involves selecting individuals who are readily available and willing to participate in the study. However, this method can lead to bias in the results, as it does not necessarily represent the entire population.

Sampling is a process of selecting a smaller group of individuals or items from a larger population for research purposes. This allows researchers to draw conclusions about the population as a whole, without having to collect data from every single individual or item, which can be time-consuming and expensive.

Selection of a Good Sample :

• Is representative of the population: The sample should be chosen in such a way that it accurately represents the population being studied. This means that every individual or item in the population has an equal chance of being selected for the sample.
• Is large enough: The sample size should be large enough to provide meaningful results. A larger sample size generally leads to more accurate and reliable results, as it reduces the impact of random variation.
• Is selected using an appropriate sampling method: The sampling method used should be appropriate for the research question and the population being studied. The method should minimize bias and ensure that the sample is representative of the population.

The selection of a representative sample is important in quantitative research. Choosing a sample that is unbiased and relevant can improve the accuracy and reliability of research findings. For instance, if the government wants to estimate the average income of households in India, studying all households is impractical. Instead, they can choose a sample of households from each state and calculate the average to arrive at an estimate. While this estimate may not be entirely accurate, it provides a good approximation of what the figure might be if all units of the population were studied.

Difference :

Basis of Comparison	Census	Sample Survey
Definition	A statistical method that study of the entire population	A statistical method that study only a representative group of population / sample of the population
Sample size	The entire population	A small proportion of the population
Data quality	Very high quality due to the comprehensive coverage of the population	Quality can vary based on the representativeness and size of the sample
Time and cost	Time-consuming and expensive	Less time-consuming and less expensive
Accuracy	Highly accurate due to the comprehensive coverage of the population	Accuracy can vary based on the representativeness and size of the sample
Data analysis	Allows for detailed analysis of population characteristics	Allows for generalization to the entire population
Error	Not present	Not present