Explain Sample Survey.

A sample survey is a research method used to collect data and draw inferences about a larger population by studying a subset or sample of that population. The goal of a sample survey is to gather accurate and representative information efficiently, without having to collect data from every individual or unit in the population.

Key characteristics of sample surveys include:

1. Sampling Design: A sample survey begins with the selection of a representative sample from the target population using various sampling techniques such as random sampling, stratified sampling, cluster sampling, or systematic sampling.

2. Data Collection: Data is collected from the selected sample using structured questionnaires, interviews, or observations. Care is taken to ensure the sample size is sufficient to provide statistically reliable results.

3. Statistical Analysis: Once data is collected, statistical methods are used to analyze the sample data and make inferences or estimates about the population parameters. Common analyses include calculating means, proportions, confidence intervals, and testing hypotheses.

4. Generalizability: The results obtained from the sample are generalized to draw conclusions about the entire population, assuming that the sample is representative and unbiased.

5. Efficiency and Cost-Effectiveness: Sample surveys are often more practical and cost-effective than conducting a complete census of the population. They allow researchers to gather valuable insights while minimizing resources and time.

Sample surveys are widely used in social sciences, market research, public opinion polling, and official statistics to study diverse topics such as demographics, health, education, consumer behavior, and economic indicators. The quality and reliability of survey results depend on the careful design of sampling methods, appropriate data collection techniques, and robust statistical analysis.