Qualitative Research Sampling Techniques

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Questions and Answers

What was the primary purpose of manufacturers and advertising agencies interviewing consumers?

To conduct a market competition analysis.

To understand consumer habits and ad effectiveness. (correct)

To train their sales staff.

To promote their products directly.

How did Suzanne gather information for her business management study?

By reading management textbooks.

By interviewing different managers at business stations. (correct)

By observing business operations in her community.

By conducting surveys with customers.

What sampling method did the Physical Education students use to gather information?

Random sampling from all students in the school.

Convenience sampling from students in the grandstand. (correct)

Systematic sampling from a list of students.

Stratified sampling from school records.

What approach did Emil use to gather historical information about his place?

Interviewing his ancestors and past officials. Signup and view all the answers

What is the main distinction between observational studies and experimental studies?

Experimental studies involve interventions, while observational studies do not. Signup and view all the answers

How many users did the company marketing need to interview for testing the new computer?

50 users. Signup and view all the answers

Which sampling design is characterized by its importance to observational studies?

Sampling design. Signup and view all the answers

What criterion did the marketing company use for selecting participants at internet cafés?

Friendliness of users. Signup and view all the answers

What is a limitation of observational study mentioned in the content?

Observation is limited to the time of occurrence of events. Signup and view all the answers

What is one advantage of the experimentation method?

Experiments can be replicated. Signup and view all the answers

Which of the following is a disadvantage of using existing data?

It has limited application to non-participants. Signup and view all the answers

What type of data is NOT mentioned as a source for existing data?

Interviews Signup and view all the answers

What is a disadvantage of the experimentation method?

It takes significant time and effort to achieve results. Signup and view all the answers

What does the rate indicate when using existing data?

The proportion of a population affected by a particular concern. Signup and view all the answers

In studying how many people are involved in fighting, when should a researcher be present?

Before the conflict ends. Signup and view all the answers

What is one advantage of using existing data in research?

It simplifies the process of defining the target population. Signup and view all the answers

What is the formula used to calculate the preceding value of the class mark (𝑴𝑖) for the interval 60 - 69?

𝑀𝑖 = (59.5 + 69.5) / 2 Signup and view all the answers

How is relative frequency (R𝑓𝑖) calculated?

R𝑓𝑖 = Frequency of the class / Total number of observations Signup and view all the answers

What does cumulative frequency (F𝑖) represent?

The frequency of a class not exceeding the upper limit Signup and view all the answers

What is the midpoint of the class interval if the lower boundary is 60 and the upper boundary is 69?

64.5 Signup and view all the answers

Which of the following statements about relative frequency is correct?

Relative frequency is expressed as a decimal or fraction. Signup and view all the answers

What is the formula used to estimate the number of classes k?

k = 1 + 3.322 log10(N) Signup and view all the answers

In the given example with 100 observations, what is the approximate value of k calculated?

8 Signup and view all the answers

How is the class width c determined in the example with a range of 65 and 8 classes?

c = 9 Signup and view all the answers

What is the range R calculated in the blood potassium level study?

2.6 Signup and view all the answers

In the blood potassium level example, how many classes k are estimated based on 40 men?

6 Signup and view all the answers

What is the highest observed blood potassium level in milliequivalents per liter from the mentioned study?

5.8 Signup and view all the answers

Using the example of fuel efficiency in cars, what would be the first step in calculating k?

Count the number of automobiles tested Signup and view all the answers

If the lowest mpg in the automobile test is 7.55, what is the highest mpg observed in the same example?

32.67 Signup and view all the answers

What is the primary purpose of obtaining a representative sample in research?

To save time and money while achieving study objectives. Signup and view all the answers

In snowball sampling, how are additional survey subjects typically identified?

By referral from current survey respondents. Signup and view all the answers

Which of the following best describes a situation where snowball sampling would be beneficial?

When studying a difficult-to-locate and small group. Signup and view all the answers

When a researcher purposely selects who can provide the best information, what sampling method are they likely using?

Judgmental sampling. Signup and view all the answers

What does a researcher primarily aim to obtain when interviewing past faculty for a historical study?

Subjective insights and personal experiences. Signup and view all the answers

What critical factor should a researcher consider when using snowball sampling?

The initial subjects' willingness to provide contacts. Signup and view all the answers

What can be a downside of the sampling method where a researcher selects those perceived to provide the best information?

It can introduce bias into the findings. Signup and view all the answers

Which of the following describes an example of snowball sampling in action?

Using referrals from known users to reach additional participants. Signup and view all the answers

Study Notes

Sampling Methods

Representative samples can be obtained through sound judgment by selecting individuals believed to have relevant information.
Sampling saves time and money by focusing on those likely to provide valuable insights.
Purposeful sampling is crucial for understanding historical contexts or under-studied phenomena.

Purposeful Sampling Example

A study on the history of a college involved interviewing past deans and pioneering faculty to gather comprehensive information.

Snowball Sampling

Involves selecting participants through referrals from initial respondents, often used when the target population is hard to reach.
One individual fitting the study profile helps identify others, creating a chain of referrals.
Particularly effective in exploratory studies with little known about the group.

Snowball Sampling Example

A researcher studying drug usage among students started with five known users, who provided additional contacts, achieving the target sample size efficiently.

Consumer Research

Companies often conduct surveys to understand consumer habits by interviewing shoppers in malls until they reach a predefined sample size.

Physical Education Study

Students surveyed peers about their experiences with a specific physical education course, achieving their target by asking those present.

Historical Research

Individuals like Emil sought historical information by engaging with ancestors and past officials.

Experimental Study Design

Sampling design impacts observational studies, where researchers collect data by observing subjects without intervention.
Experimental studies involve intervention to assess influences on responses.

Direct Observation Limitations

Observational studies have timing constraints; researchers must be present during events to collect accurate data.

Experimentation Method

Experiments can be replicated, allowing for consistency in data collection.
They may consume significant time and resources, especially if initial results are unsatisfactory.

Existing Data Utilization

Researchers use existing documents and online resources to gather secondary data on incidence and prevalence.
Benefits include improved target population definition and study design planning.

Limitations of Existing Data

Agency records may not represent individuals outside their programs, limiting the generalizability of findings.

Statistical Class Construction

Determine the number of classes (k) and class width (c) through established formulas based on data observations.
For example:
- For 100 observations ranging from 20 to 85: k ≈ 8 classes, c ≈ 9.
- For blood potassium levels (3.2 to 5.8): k ≈ 6 classes, c ≈ 0.5.

Class Mark Calculation

The class mark is the midpoint of a class interval, calculated using the lower and upper limits of that interval.

Relative Frequency (Rf)

Represents the frequency of a specific class as a proportion of the total number of observations (Rf = f/n).

Cumulative Frequency (Fi)

Indicates the sum of all frequencies for classes, representing the total observations that do not exceed the class's upper limit.

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Description

This quiz explores the methods and importance of qualitative research sampling techniques. Understand how researchers use sound judgment to select participants and its implications for the study’s validity. It emphasizes constructing historical realities and describing phenomena through targeted sampling.