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KFP6014 KAEDAH TINJAUAN

TUGASAN 2: HISTORY OF RESEARCH, TYPES OF SURVEYS & MINI SAMPLES

KUMPULAN

PENSYARAH: PROF. MADYA DR. QISMULLAH YUSUF

NAMANO ID/MATRIKNO.TELEFONEMAIL

PREMA A/P VIJAYAKUMAR

REVATHY A/P MUNIANDYM20142001713

M20142001873010-3710655

014-9441772

[email protected]

[email protected]

Ques 2: Types of surveys & mini samples of the surveys

Types of samplesThe best sampling is probability sampling, because it increases the likelihood of obtaining samples that are representative of the population.Probability sampling (Representative samples)Probability samples are selected in such a way as to berepresentativeof the population. They provide the most valid or credible results because they reflect the characteristics of the population from which they are selected (e.g., residents of a particular community, students at an elementary school, etc.). There are two types of probability samples: random and stratified.Random sampleThe termrandomhas a very precise meaning.Each individual in the population of interest has an equal likelihood of selection.This is a very strict meaning -- you can't just collect responses on the street and have a random sample.

The assumption of anequal chance of selectionmeans that sources such as a telephone book or voter registration lists are not adequate for providing a random sample of a community. In both these cases there will be a number of residents whose names are not listed. Telephone surveys get around this problem by random-digit dialing -- but that assumes that everyone in the population has a telephone. The key to random selection is that there is no bias involved in the selection of the sample. Any variation between the sample characteristics and the population characteristics is only a matter of chance.Stratified sampleA stratified sample is a mini-reproduction of the population. Before sampling, the population is divided into characteristics of importance for the research. For example, by gender, social class, education level, religion, etc. Then the population is randomly sampledwithineach category orstratum. If 38% of the population is college-educated, then 38% of the sample is randomly selected from the college-educated population.

Stratified samples are as good as or better than random samples, but they require a fairly detailed advance knowledge of the population characteristics, and therefore are more difficult to construct.How to Construct a probability (representative) sampleNonprobability samples (Non-representative samples)As they are not truly representative, non-probability samples are less desirable than probability samples. However, a researcher may not be able to obtain a random or stratified sample, or it may be too expensive. A researcher may not care about generalizing to a larger population. The validity of non-probability samples can be increased by trying to approximate random selection, and by eliminating as many sources of bias as possible.Quota sampleThe defining characteristic of aquota sampleis that the researcher deliberately sets the proportions of levels or strata within the sample. This is generally done to insure the inclusion of a particular segment of the population. The proportions may or may not differ dramatically from the actual proportion in the population. The researcher sets aquota, independent of population characteristics.Two of each species

Example:A researcher is interested in the attitudes of members of different religions towards the death penalty. In Iowa a random sample might miss Muslims (because there are not many in that state). To be sure of their inclusion, a researcher could set a quota of 3% Muslim for the sample. However, the sample will no longer be representative of the actual proportions in the population. This may limit generalizing to the state population. But the quota will guarantee that the views of Muslims are represented in the survey.Purposive sampleApurposive sampleis a non-representative subset of some larger population, and is constructed to serve a very specific need or purpose. A researcher may have a specific group in mind, such as high level business executives. It may not be possible to specify the population -- they would not all be known, and access will be difficult. The researcher will attempt to zero in on the target group, interviewing whomever is available.

A subset of a purposive sample is asnowball sample-- so named because one picks up the sample along the way, analogous to a snowball accumulating snow. A snowball sample is achieved by asking a participant to suggest someone else who might be willing or appropriate for the study. Snowball samples are particularly useful in hard-to-track populations, such as truants, drug users, etc.

Convenience sampleAconvenience sampleis a matter of taking what you can get. It is anaccidentalsample. Although selection may be unguided, it probably is not random, using the correct definition of everyone in the population having an equal chance of being selected. Volunteers would constitute a convenience sample.

Non-probability samples are limited with regard to generalization. Because they do not truly represent a population, we cannot make valid inferences about the larger group from which they are drawn. Validity can be increased by approximating random selection as much as possible, and making every attempt to avoid introducing bias into sample selection.Examples of nonprobability samplesSelf-test #1: Sample typesSelf-test #2: Using the random numbers tableContinue on toSample size

Exploratory ResearchExploratory researchis an important part of any marketing or business strategy. Its focus is on the discovery of ideas and insights as opposed to collecting statistically accurate data. That is why exploratory research is best suited as the beginning of your total research plan. It is most commonly used for further defining company issues, areas for potential growth, alternative courses of action, and prioritizing areas that require statistical research.When it comes to online surveys, the most common example of exploratory research takes place in the form ofopen-ended questions. Think of the exploratory questions in your survey as expanding your understanding of the people you are surveying. Text responses may not be statistically measureable, but they will give you richer quality information that can lead to the discovery of new initiatives or problems that should be addressed.Descriptive ResearchDescriptive researchtakes up the bulk of online surveying and is considered conclusive in nature due to its quantitative nature. Unlike exploratory research, descriptive research is preplanned and structured in design so the information collected can be statistically inferred on a population.The main idea behind using this type of research is to better define an opinion, attitude, or behaviour held by a group of people on a given subject. Consider your everyday multiple choice question. Since there are predefined categories a respondent must choose from, it is considered descriptive research. These questions will not give the unique insights on the issues like exploratory research would. Instead, grouping the responses into predetermined choices will provide statistically inferable data. This allows you to measure the significance of your results on the overall population you are studying, as well as the changes of your respondents opinions, attitudes, and behaviours over time.Causal ResearchLike descriptive research,causal researchis quantitative in nature as well as preplanned and structured in design. For this reason, it is also considered conclusive research. Causal research differs in its attempt to explain the cause and effect relationship between variables. This is opposed to the observational style of descriptive research, because it attempts to decipher whether a relationship is causal through experimentation. In the end, causal research will have two objectives: 1) To understand which variables are the cause and which variables are the effect, and 2) to determine the nature of the relationship between the causal variables and the effect to be predicted.For example, a cereal brand owner wants to learn if they will receive more sales with their new cereal box design. Instead of conducting descriptive research by asking people whether they would be more likely to buy their cereal in its new box, they would set up an experiment in two separate stores. One will sell the cereal in only its original box and the other with the new box. Taking care to avoid any outsidesources of bias, they would then measure the difference between sales based on the cereal packaging. Did the new packaging have any effect on the cereal sales? What was that effect?

Ques 1 :

History of Research