Data Gathering Techniques and Sample Size Determination

Sources of Data

Origin points for collecting necessary information.

Data Profiles

Existing records used for data analysis.

Surveys

Questionnaires designed to gather information from respondents.

Interviews

Direct conversations to collect qualitative data.

Probability Sampling

Sampling method where every individual has a chance.

Non-Probability Sampling

Sampling method without random selection of participants.

Sample Size Determination

Process of deciding how many subjects to include.

Slovin's Formula

Formula used to calculate sample size based on population.

Confidence Interval

Range within which a population parameter lies.

Degree of Variability

Extent to which data points differ from each other.

Cochran's Formula

Statistical method for determining sample size for proportions.

Population Proportion

Fraction of the population with a particular attribute.