POPULATION AND SAMPLE.TYPES OF SAMPLING PROCEDURES

A group or class of subjects, variables, concepts, or phenom­ena is called sample.

In some cases, an entire class or group is investigated; The process of examining every member in a population is called a census.

A sample is a subset of the population that is representative of the entire population.

SAMPLE SIZE

Determining an adequate sample size is one of the most controversial aspects of sampling. The size of the sample required for a study depends on at least one or more of the following seven factors:

(1) project type,

(2) project purpose,

 (3) project complexity,

(4) amount of error tolerated,

(5) time constraints,

(6) financial constraints, and

(7) previous research in the area.

1. A primary consideration in determining sample size is the research method used. Focus groups (see Chapter 5) use samples of 6-12 people, but the results are not intended to be generalized to the population from which the respondents are selected. Samples with 10-50 subjects are commonly used for pretesting measurement instruments and pi­lot studies, and for conducting studies that will be used for only heuristic value. 

2.    Researchers often use samples of SO, 75, or 100 subjects per group, or cell More than likely, the client would accept SO respondents in each of the eight cells, producing a sample of 400 (8 X SO).

3.    Cost and time considerations always control sample size. Although researchers may wish to use a sample of 1,000 for a survey, the economics of such a sample are usually prohibitive.

4.    Most research is conducted using a sample size that conforms to the project's budget. Researchers may be wise to consider using smaller samples for most projects.

5.    Multivariate studies require larger samples than do univariate studies because they involve analyzing multiple response data.

6.    For panel studies, central location test­ing, focus groups, and other pre recruit proj­ects, researchers should always select a larger sample than is actually required. If a survey is planned and similar research indicates that a representa­tive sample of 400 has been used regularly with reliable results, then a sample larger than 400 may be unnecessary.

7.    Generally speaking, the larger the sample, the better. However, a large un­representative sample (The Law of Large Numbers) is as meaningless as a small un­representative sample.

TYPES OF SAMPLING PROCEDURES

There are a variety of sampling methods available for researchers. We first need to discuss the two broad categories of sam­pling: probability and nonprobability.

Probability and Nonprobability Sampling

Probability sampling uses mathematical guidelines whereby each unit's chance for se­lection is known.

 Nonprobability sampling does not follow the guidelines of mathemati­cal probability.

There are four issues to consider when deciding whether to use probability or non-probability sampling:

·  Purpose of the study.

·  Cost versus value.

·  Time constraints.

·  Amount of acceptable error.

Types of Non probability Sampling

Mass media researchers frequently use non prob­ability sampling, particularly in the form of available samples.

An available sample (also known as a convenience sample) is a collection of readily accessible subjects, ele­ments, or events for study.

In most situations, available samples should be avoided because of the bias in­troduced by the respondents' proximity to the research situation, but available sam­ples can be useful in pretesting question­naires or other preliminary (pilot study)

The purposive sample, Purposive samples are used frequently in mass media studies when researchers select respondents who use a spe­cific medium and are asked specific questions about that medium. A purposive sample is chosen with the knowledge that it is not repre­sentative of the general population.

For example, a researcher interested in find­ing out how other internet providing agents  differ from geo  accessibility.

Snow­ball Sampling. A researcher  randomly contacts a few qualified respondents and then asks these people for the names of friends, relatives, or acquaintances they know who may also qual­ify for the research study.

Types of Probability Samples

The most basic type of probability sampling is the simple random sample, where each sub­ject, element, event, or unit in the population has an equal chance of being selected.

 Sampling with replacement is often used in more complicated research studies such as nationwide surveys. For example, a researcher who wants to analyze 10 prime-time television programs out of a population of 100 programs to de­termine how the medium portrays elderly people can take a random sample from the 100 programs by numbering each show from 00 to 99 and then selecting 10 numbers from a table of random numbers, such as the brief listing in Table 4.1

SIMPLE RANDOM SAMPLING

Advantages

1.     Detailed knowledge of the population is not required.

2.     External validity may be statistically inferred.

3.     A representative group is easily obtainable.

4.     The possibility of classification error is eliminated.

Disadvantages

1.     A list of the population must be compiled.

2.     A representative sample may not result in all cases.

3.     The procedure can be more expensive than other methods.

SYSTEMATIC SAMPLING

Advantages

1.     Selection is easy.

2.     Selection can be more accurate than in a simple random sample.

3.     The procedure is generally inexpensive.

Disadvantages

1.     A complete list of the population must be obtained.

2.     Periodicity (arrangement or order of list) may bias the process.

ADDRESS-BASED SAMPLING (ABS):  A third type of random selection method called address-based sampling (ABS) to recruit sample households. The method uses randomly selected addresses. There are several methods to develop ran­dom numbers or households, but two rules always apply:

(1) each unit or subject in the population must have an equal chance of be­ing selected,

(2) and  the selection procedure must be free from subjective intervention by the researcher.

A STRATIFIED SAMPLE is the ap­proach used to get adequate representation of a subsample. The characteristics of the sub-sample (strata or segment) may include almost any variable: age, gender, religion, income level, or even individuals who listen to specific radio stations or read certain magazines. The strata may be defined by an almost unlimited number of characteristics; however, each ad­ditional variable or characteristic makes the subsample more difficult to find and costs to find the sample increase substantially.

Stratified sampling ensures that a sample is drawn from a homogeneous subset of the population—that is, from a population that has similar characteristics. Homogeneity helps researchers to reduce sampling error.

Stratified Sampling

Advantages

1.     Representativeness of relevant variables is ensured.

2.     Comparisons can be made to other populations.

3.     Selection is made from a homogeneous group.

4.     Sampling error is reduced.

Disadvantages

1.     Knowledge of the population prior to selection is required.

2.     The procedure can be costly and time-consuming.

3.     It can be difficult to find a sample if incidence is low.

4.     Variables that define strata may not be relevant.

CLUSTER SAMPLING : Select the sample in groups or categories; this procedure is known as cluster sampling. For example, analyzing magazine readership habits of people in  Tamilnadu would be time-consuming and com­plicated if individual subjects were randomly selected. With cluster sampling, the state can be divided into districts, and groups of people can be selected from each area.

Cluster Sampling

Advantages

1.     Only part of the population need be enumerated.

2.     Costs are reduced if clusters are well defined.

3.     Estimates of cluster parameters are made and compared to the population.

Disadvantages

1.     Sampling errors are likely.

2.     Clusters may not be representative of the population.

3.     Each subject or unit must be assigned to a specific cluster.

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Content analysis.USES ,LIMITATIONS

The method is popu­lar with mass media researchers because it is an efficient way to investigate the content of the media, such as the number and types of commercials or advertisements in broadcast­ing or the print media. 

Content analysis can be traced back to World War II, by comparing the mu­sic played on German stations with that on other stations in occupied Europe,After the war, researchers used content analysis to study propaganda in newspapers and radio.

An informal content analysis of three journals that focus on mass communication research (Journal of Broadcasting & Electronic Media, Journal^­ism and Mass Communication Quarterly, and Mass Communication and Society) from 2007 to 2008 found that content analysis was still a popular method, used in about one-third of all published articles.

DEFINITION OF CONTENT ANALYSIS

There are many definitions of content analysis.

Kerlinger's (2000) definition is fairly typi­cal: Content analysis is a method of studying and analyzing communication in a system­atic, objective, and quantitative manner for the purpose of measuring variables.  Kerlinger's definition involves three con­cepts that require elaboration.

First, content analysis is systematic.

This means that the content to be analyzed is selected accord­ing to explicit and consistently applied rules: Sample selection must follow proper pro­cedures, and each item must have an equal chance of being included in the analysis. Moreover, the evaluation process must be 

systematic: All content under consideration is to be treated in exactly the same manner.

Second, content analysis is objective;

The researcher's personal biases should not enter into the findings. The analysis should yield the same results if another researcher replicates the study.

Third, content analysis is quantitative. 

The goal of content analysis is an accurate representation of a body of messages. Quan­tification is important in fulfilling that ob­jective and it aids researchers in the quest for precision,  sum­marize results and to report them concisely.  It  gives research­ers additional statistical tools that can aid in interpretation and analysis.

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Interviewing

Writing the news story is only half the story.  Getting the story is the other half.

The most important way journalists get stories is by interviewing people they plan to write about. So conducting interviews is one of the key tasks of journalism. Interviewing is an essential skill for journalists.

 Interviews may be conducted over the telephone or in person. There are advantages to both approaches. 

On the other hand, when we interview someone in person, we are better able to perceive nuance by observing body language, facial expression and other hints. 

The successful interview is depending on preparation.
Basic strategies for conducting an interviews.

https://www.youtube.com/watch?v=lYYE8zt0xFc

Research:  Do at least some research before every interview so that we understand the basic outlines of the story.   Court records, academic textbooks, journalistic databases, the record of colleagues, other journalists and former and present associates of the person are all appropriate places to look.

Sales Pitch.  Many interview subjects are nervous about being interviewed, So that journalist  should be prepared to explain to our interview subject why they're important and essential to our story.

Make a List.  Prepare a list of questions that need to ask and the order in which we will ask questions. It is a good idea to start with softer, more general questions and move to tougher questions . A list will help us  stay on track  and to keep us away from sensitive questions. Ask basic questions first then controversial questions. Questions need to be brief.

Request and Identify Our self. Always clearly and honestly state who you are, who you work for and what you want to do. Be prepared to negotiate politely with a secretary.

Dress Appropriately.  Many reporters try to strike a reasonable balance: nothing too fancy, nothing to ragged. If you are interviewing religious people in a place of worship, be respectful of their traditions - be prepared to wear religious headgear if requested, take your hat off in a church. If you are a woman, you may want to pack a headscarf for this reason.

Be on time! . Always be on time. If you simply cannot avoid being late,  Early is better than late, but don't be so early you're a nuisance.

First, break the ice. Don't start off an interview by being confrontational. Try to seat yourself in a comfortable, non-confrontational position. Introduce yourself and re-state your purpose. Look for ways to establish rapport. But don't waste too much time on this phase. 

Use a  diplomacy &  conversational style. You're not a police officer and this isn't an interrogation.  Use diplomacy and tact to present your questions in a conversational style. This will almost always work better.

Start with an easy question. To ask tough questions not advisable 

Use open-ended and closed questions. Closed questions require a specific answer. Open-ended questions provide the interview subject with an opportunity to elaborate and provide explanation.

Ask follow-up questions. When the person you're interviewing answers one question, you may want to conversationally follow her lead and move to a follow-up question. .

Try to stay in control. Some interview subjects will try to "run out the clock" .  It's your job as the interviewer to keep track of time and get back to the core questions if they move too far away. Don't be rude, but try to keep the interview on track.

Repeat important questions. Your subject won't answer a question. Politely ask it again. Maybe use different words the second or third time. 

Request definitions. Don't pretend to understand jargon if you don't.  So always ask for explanations of terms you are not familiar with, or technical aspects of the story.

Check and re-check. Always to spell names and technical terms. Get them to confirm their title and all information you have taken down is correct. 

On taking notes in interviews

When you interview someone, you have to be able to transfer the information you hear to your story. You have three options: memory, notes or recording. Each have their

Summary

- Interviewing is one of the key tasks of reporting.

- If reporters can't get the story without conducting interviews, they need to develop strategies for conducting effective interviews.

- Preparation is the key to a successful interview.

- Do some research.

- Prepare a sales pitch to get a reluctant source to talk to you.

- Make a list of questions.

- Request an interview and identify yourself.

- Dress appropriately.

- Always be on time.

- When you're conducting the interview, start with gentle icebreaker conversation.

- Use a conversational style.

source :

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Reporting and Editing. Source of news

Reporting

Reporting, means collection or gathering of facts about current events or background material required for a news story or feature.

Reporters do it through interviews, investigations and observation. Reporters are given directions by editors to cover a particular event, known as assignments. They may be general assignments or special ones. Reporters write the news stories, which are called copies. A reporter should write with clarity, objectivity and accuracy. A reporter who covers a particular area or subject specialises in that.

Editing:

A person who edits is called an editor. Editing is a process by which a report is read, corrected, modified, value-added, polished, improved and made better for publication. Condensation is also part of editing.

The copy of the report has been improved by the editor and is therefore easier to read and understand. The editor also decides whether photographs or other images or graphs should be used along with the report. A good editor needs creative skills, command over the language, ideas to improve the copy and correct judgement about how much importance should be given to a particular news item.

We call a news report a news story. These are factual stories - events that have happened or things that are going to happen. Like a good story teller, the reporter has to narrate the story before the reader or listener or viewer. reporters get news stories from various sources.

The following are the main sources:

a)      Listening: A reporter can get good stories by listening to others. The reporter goes to the accident site to collect all this information. The reporter's job does not end there. He has to inform the photographer about the accident. The next day's newspaper should also carry some good photographs about the accident.

b)      Covering events : "India-Pakistan cricket Test in Mumbai", Kumbhmela in Haridwar", "International Film Festival in Goa ", these are all events. Reporters cover these events for their publications, channels or new bulletins. The coverage depends upon the importance and magnitude of the event. A small panchayat level meeting will be covered locally, whereas a state level function will get wider coverage. If it is a national event, it will receive nationwide attention.

c)      Press conferences: Another major source of news is the press conference. Leaders of political parties hold press conferences regularly. Ministers also hold press conferences to announce various programmes and policies of the government. Business houses arrange press conferences to launch their new products. Organisations and Associations also held press briefings.

d)      Reports and statements:. These are another major sources of news items. Various commissions and committees submit their reports to the Government which are a goldmine as far as news reporters are concerned.

e)      Parliament and Assemblies:- Parliament and state assemblies when in session generate lot of news. Questions in both the houses of parliament, proceedings, calling attentions, zero-hour mentions, debates and various acts passed by the parliament also make news. The general budget and railway budget are presented in parliament. State budgets are presented in state assemblies.

lice sources: The police are in charge of law and order. So the police always maintain a close vigil about various activities of citizens. Reporters get details about crime, accidents etc. from police sources.

g) Interviews: Interviewing people connected with an event or incident is a very common practice used by reporters to get details. Television reporters take the opinion of people which are called reactions. Occasionally, reporters of newspapers and channels conduct long interviews with important people.

News can also originate from government and non-government sources, courts, airports, railway stations, educational institutions, hospitals etc.

source:http://download.nos.org/srsec335new/ch7.pdf

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