Collection of Data Test - 20

The National Sample Survey Organisation (NSSO) primarily collects primary data through sample surveys conducted across various sectors and topics in India. These surveys cover a wide range of socio-economic aspects such as employment, income, consumption, education, health, housing, agriculture, and many others. 

The source of data that is collected and compiled by others is known as secondary data. Secondary data refers to data that has been collected and compiled by others for purposes other than the researcher's current project. This data is often available in various forms such as published reports, articles, databases, or government records.

A pilot survey involves testing the survey questions on a small sample of respondents to assess their clarity, understandability, and appropriateness before conducting the full-scale survey. If difficulties arise during the pilot survey, questions can be adjusted or reframed accordingly to improve their effectiveness.

The Census of India is conducted at regular intervals of 10 years to gather demographic and socio-economic data about the population. This data collection process provides vital information about the population's size, distribution, composition, and other socio-economic characteristics, which is crucial for planning and policy-making at various levels of governance. 

Secondary sources of data are indeed obtained from sources that have already collected the data, such as published materials like government reports, documents, newspapers, and other similar sources. These sources provide data that has been collected and analyzed by others, making it readily available for further analysis or research.

Observation is a primary data collection method where researchers directly observe and record behaviors, events, or phenomena as they naturally occur in their real-world context. One common form of observation involves tracking behavior over a period of time, either continuously or intermittently, to understand patterns, trends, or relationships. This method allows researchers to gather firsthand information without relying on self-reporting or interpretation by participants, making it valuable for studying behaviors, interactions, and processes in various settings.

Sampling bias is an example of an error in data acquisition. It occurs when the method of sampling systematically favors certain outcomes over others, leading to a non-representative sample. This bias can distort the findings of a study and compromise the validity and generalizability of the results.

Increasing the sample size typically reduces the sampling error. This is because larger sample sizes provide more representative data, allowing for more accurate estimates of population parameters and reducing the variability between samples. As a result, the margin of error, or sampling error, decreases with larger sample sizes.

Lottery method is the method of Unrestricted random sampling In unrestricted random sampling, each member of the population has an equal chance of being selected for the sample. The lottery method is a simple and straightforward approach where individuals from the population are selected randomly, often by drawing names or numbers from a container, ensuring that every member has an equal opportunity to be chosen. 

The incorrect statement among the options is:

"The investigator meets and collects information from the informants directly, in the case of an indirect interview."

An indirect interview typically does not involve the investigator meeting and collecting information directly from the informants. Instead, in an indirect interview, the investigator may gather information through intermediaries or secondary sources, such as documents, records, or other individuals who have knowledge about the informants or the subject of the research.