Sampling and sampling distributions
- 1. Sampling and sampling distributions Presented By Group 6: Abhishek Kr. Singh Noorul Ameera K.K. Deepak V Ilapakurti Sai Krutika
- 2. Definition • Sampling is used to describe a portion chosen from the population. • Sample is the representative subset of the population. • Example : Choosing 20 students from a class of 60 students. • Here population size:60,sample size:20
- 3. Statistics and Parameters • Characteristics of sample are called as Statistics. • Characteristics of population are called as parameters. POPULATION SAMPLE Population Size = N Sample Size = n Population Mean = µ Sample Mean = xˉ Population S.D.= σ Sample S.D= s
- 4. Types of Sampling • 1.Non-random or judgement sampling. • 2.Random or probability sampling.
- 5. Types of Random sampling • 1.Simple Random sampling • 2.Systematic sampling • 3.Stratified sampling • 4.Cluster sampling
- 6. Simple Random sampling • All Objects in the population have an equal chance of being the sample. • It is not bias , but difficult to carry out in practice.) i.e; if you have 100 things in your population each one can potentially be included in the population.
- 8. Stratified sampling • Population is broken into non overlapping groups, then a sample from each group is taken.
- 9. Cluster Sampling • In Cluster Sampling we divide the population into groups, or clusters, and then select a random sample of these clusters.
- 11. Types of Non-Random sampling • Convenience Sampling • Judgement sampling • Quota sampling • Shopping-mall Intercept sampling • Snowball sampling
- 13. Judgmental Sampling • Researchers draws a sample which he thinks is representative of the population or otherwise appropriate. • It is also called as purposive sampling.
- 16. Shopping Mall OR Intercept Sampling • This sample involves drawing samples from the market places, shopping malls, so to make sample representative of the population .
- 17. Snowball Sampling • Initial respondents are selected randomly and then additional respondents are selected by their referrals and so on. The scheme is also known as Multiplicity Sampling.
- 21. In this scenario detective used a sampling technique called Snowball Sampling We should use this technique when participants are hard to find like: a study, investigation, inquiry etc. It allows for studies to take place otherwise it’s impossible to conduct- due to lack of participants.
- 22. THANKYOU