Sampling techniques pdf notes

A manual for selecting sampling techniques in research. Presents construction of sampling frames, area sampling, methods of estimation, stratified sampling, subsampling, and sampling methods for surveys of human populations. Based upon the data collected fro these samples conclusions are drawn upon the whole universe. To study the consumption pattern of households, the people living in houses, hotels, hospitals, prison etc. Types of sampling methods statistics article khan academy. A sampling frame for voters in a precinct would be the voter registration listing, for example. If anything goes wrong with your sample then it will be directly reflected in the final result.

We will describe the mechanics of random sampling shortly, but we want to note again that in some cases random sampling procedures simply are not possible. The people who take part are referred to as participants. Simple random sampling, systematic sampling, stratified sampling fall into the category of simple sampling techniques. A sampling frame is a list of the actual cases from which sample will be drawn. The object of sampling is thus to secure a sample which will represent the population and reproduce the important characteristics of the.

If youre behind a web filter, please make sure that the domains. Raj, p4 all these four steps are interwoven and cannot be considered isolated from one another. Statistical thinking statistical thinking will one day be as necessary for e cient citizenship as the ability to read and write. According to showkat and parveen 2017, the snowball sampling method is a nonprobability sampling technique, which is also known as referral sampling, and as stated by alvi 2016, it is. Under this technique some representative units or informants are selected from the universe. A manual for selecting sampling techniques in research 4 preface the manual for sampling techniques used in social sciences is an effort to describe various types of sampling methodologies that are used in researches of social sciences in an easy and understandable way. A better representative sample is produced using probability sampling techniques. Sampling problems may differ in different parts of the population. Sampling techniques basic concepts of sampling essentially, sampling consists of obtaining information from only a part of a large group or population so as to infer about the whole population. It is one of the most important factors which determines the accuracy of your researchsurvey result. But it is possible if just only one sampling technique. Using random procedures allows the use of probability sampling methods. The population consists of the totality or aggregate of the observations with which the researcher is concerned 3.

Probability sampling techniques linkedin slideshare. Every member of the population is equally likely to be selected. Population divided into different groups from which we sample randomly. Brief notes on sampling method of data collectionthese selected units are called samples. Contacting members of the sample stratified random sampling convenience sampling quota sampling thinking critically about. Read and learn for free about the following article. Note that a random sample is not always the most representa tive, especially. A sample is the group of people who take part in the investigation. Insights from an overview of the methods literature abstract the methods literature regarding sampling in qualitative research is characterized by important inconsistencies and ambiguities, which can be problematic for students and researchers seeking a clear and coherent understanding. The probability distribution consisting of all possible sample statistics of a given sample size selected from a population using one probability sampling.

This is suggested by the name strata, with its implication of a division into layers. Most of the notes in this lecture are directly taken or slightly. Disadvantages a it is a difficult and complex method of samplings. Sampling distribution of sample statistic sampling distribution of sample statistic. There are lot of techniques which help us to gather sample depending upon the need and situation. Due to some recent advancement in the digital signal technology over the last past few decades the light weight, programmable and easily reproducible discrete time systems are available. Why sampling oscilloscopes the general need for sampling systems is caused by the normal gainbandwidth limitations of amplifiers. We described procedures for drawing samples from the. Sampling notes objective these sampling notes are offered as an aid to the user of tektronix sampling systems. Population is an accessible group of people who meets a welldefined set of eligibility criteria. A population is a group that we want to find information about. Population, sample and sampling distributions i n the three preceding chapters we covered the three major steps in gathering and describing distributions of data.

Notes on sampling and hypothesis testing allin cottrell. Sampling for a chemical analysis necessarily requires the use of statistics because conclusions will be drawn about a much larger amount of material from the analysis of a small laboratory sample. Topics include populations, census, sample surveys, sampling units, sampling frames, random sampling, systematic sampling, stratified sampling and quota sampling. The explanations below are meant to help you understand the reasons for using each method. If each stratum is homogeneous, in that the measurements vary little from one unit to another, a precise estimate of any stratum mean can be obtained from a small sample in that. It is useful when the researcher know little about a group or organisation. A better representative sample is produced using probability sampling technique s. Sampling theory chapter 4 stratified sampling shalabh, iit kanpur page 5 now 1 1 1 1 k stii i k i i i ey ney n ny n y thus yst is an unbiased estimator of y. It might be a group of people or it could be simply a group of numbers.

Sampling techniques communication engineering notes in pdf form. Statisticsis the science of collecting, analyzing, and interpreting data in such a way that the conclusions can be objectively. Oct 25 notes 51799 views 24 comments on sampling techniques their are two types of signal exist, continuous time signal and discrete time signals. Sampling for qualitative research with careful sampling and equally careful collection techniques, a surprisingly small number of interviews, narratives or focus groups can yield the data to answer your research question. As data collectors, you will not be responsible for selecting the sampling method. Hence the sample collected through method is not random in nature. Inferences drawn from sample are generalizable to the. The three will be selected by simple random sampling. Simple random sampling in an ordered systematic way, e. The table of the largest corporations in fortune magazine is the sampling frame for large corporations.

Lets begin by covering some of the key terms in sampling like population and sampling frame. Statistical methods sampling techniques statstutor. It basically states that a bandlimited time function can be exactly reconstructed from equally spaced samples provided that the sampling rate is sufficiently highspecifically, that. Ch7 sampling techniques university of central arkansas. Sampling, measurement, distributions, and descriptive statistics chapter 9 distributions. Students use stata or another comparable package to implement designs and analyses of survey data. Advantages a it is a good representative of the population. Sampling is the process of selecting a representative group from the population under study. Sampling techniques introduction to sampling distinguishing between a sample and a population simple random sampling step 1. Use a variety of sources for thecollection of data, both primary and secondary1. Concepts and systems are discussed, with references of some texts included for additional study. Each entry on the sampling frame is called a sampling unit.