qualitative research sampling is non random selection

Published: Last Edited:

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

The main difference between quantitative and qualitative research is their method of selecting samples. First, quantitative research is a scientific method using probability sampling while qualitative research is non-probability sampling method. Quantitative sampling is random selection which means every member of population has equal chance of being selected (Del Balso and Lewis 2005). It emphasizes on selecting a large size of samples for generating and ensuring the representativeness of the characteristic of population. In contrast, qualitative research sampling is non random selection where which means every population of being selected has unknown chance (Babbie 2007). It concerns on selecting specific and small sizes of sample population for understanding social life

Second difference is the adoption of techniques in the procedure of sampling design for ensuring the quality. Quantitative sampling permits to use of various statistical sampling design for estimating error in different situations (Babbie 2007). They include simple random, systematic, stratified and multistage cluster sampling. For example, stratified random sampling is used to divide population into groups such men and women. Then, the samples are selected equally from each group. It can ensure the representativeness of subgroup and reduce the degree of error. Differently, qualitative research sampling is not tended to ensure representativeness. It mostly uses convenience, purposive, quota and snowball sampling for obtaining information about social groups in real life.


One major difference of the measurement between them is the timing in measuring data. Quantitative researchers mostly 'think about variables and convert them into specific actions during a planning stage that occurs before and separate from gathering or analyzing data' (Neuman 2006, p16-17). Differently, qualitative researchers occur in the process of collecting data. That means researchers measuring data before gathering data and can develop new questions as well as come up with new ideas during collecting data.

Moreover, the technique in measuring data is also different. Quantitative research develops systematic techniques to produce numerical data which can move from abstract ideas or variables to specific data measurement (Neuman 2006). Differently, qualitative research measures the data not only in the form of number, but also includes written, spoken words, actions, sounds or visual images, such as photographs, videos, maps.

Data analysis

First, the technique of data analysis is different. In quantitative research, statistical methods are mainly used for analyzing data in order to discovering the relationship between variables (Babbie 2007). For example, researchers run the collected data through coding into the SPSS software. The techniques of data analysis in quantitative research are various such as univariate analysis, subgroup comparisons, bivariate and multivariate analysis. In contrast, qualitative analysis is the non-numerical tests through interpretation of observations by researchers. Qualitative data analysis basically requires researchers to organize the data, to peruse the entire data, to identify general categories of data, and then to integrate and summarize the data where these steps are Creswell's idea (Leedy and Ormrod 2010).

Besides, they use different ways to present the result of data analysis. In quantitative research, it is presented by a series of numbers, in tables, or graphics, figures, matrix, or diagrams (Leedy and Ormrod 2010). Differ to quantitative research, collected data mostly consist of words, pictures, and observations of cases which can be presented in the narrative form such as written or spoken words.

Total words: 540

Compare the strengths and weaknesses of quantitative and qualitative research. (50%) Illustrate your answer with appropriate research situations. (20%)


During the process of designing and implementing the research and generalize results, quantitative and qualitative researches both have some strengths and weaknesses due to different aims and methods for conducting research. This part would generally focus on some of aspects including the flexibility of research design, procedure of data collection, detailed information about real social life, level of measurement, and representativeness of data result to consider the strengths and weaknesses between them.


Flexibility of research design

First, in the flexibility of research design for researchers, qualitative research seems more strengthen than quantitative research. Actually, qualitative research does not have an exact standardized instrument in designing research questions. Thus, questions are changeable and modifiable whenever appropriate during the research (Neuman 2006). For example, when doing any of in-depth interview, it allows the researchers to change and create their questions and ideas base on the situation of participant's response, instead of following the questions they prepare before. Therefore, it shows that qualitative methods allow researcher has greater freedom and flexibility to modify research design any time.

Contrarily, it could be a critic that quantitative research is less flexible due to the preplanned, structured and standardized instruments before implementing questionnaires (Neuman 2006). Researchers just follow the instruments and unaware of the new variable. For example, surveys with questionnaires allow researchers asking all participants identical questions in the same order. Particularly some questionnaires are 'closed-ended' (Babbie 2007). Like the questions about the attitude of abortion, it may ask 'do you support the behavior of abortion?' Here, the respondents can only answer 'yes' or 'no'. Thus, it is too relied on highly structured questionnaires so as lack flexibility.

Procedure of data collection

However, such standardized instrument can be indicated that the process of data collection is more systematic so that it is strength because it is easier for researchers to follow. For example, when doing a telephone survey about Hong Kong citizens' voting intentions, the researchers are just required to ask participants exactly the same questions and have to impute the same intention to all respondents giving a particular response (Babbie 2007).

In contract, it is complex in doing qualitative research as it really depends on the quality of researchers' skills. For example, when doing an in-depth interview about the culture of a small village, it allows respondents to respond on their own words r, rather than forcing them to choose from fixed responses. In this way, some interviewers may possibly misinterpret and misclassify a response.

Detailed information about real social life

In capturing the in-depth data about social phenomenon in real social life, qualitative research is more strengthen than quantitative research. Qualitative research seeks to observe phenomena for having deeper understand about the complicated reality (Babbie 2007). It employs participant observation, in-depth interview, and focus group to obtain a specific type of human behavior, attitudes and motivation within wider text in natural settings. For example, to conduct a case study about the smoking culture among adolescents, researchers can participate to those smoking groups for observing and interacting with them. Researchers can ask the in-depth opinions about smoking. Therefore, researchers can explore their attitudes and real opinions about the issue.

Differently, quantitative research is being criticized that it is weak to provide detailed and in-depth information about participants' feelings and opinions (Babbie 2007). The survey research with questionnaire may provide information in some area, but it rarely develops the questions about the total situation that what respondents are thinking, feeling and acting. For example, if there is a survey about job satisfaction. Questionnaires may only include the degree of satisfaction about the jobs but seldom ask them for in-depth opinion about what they think. Therefore, it may incapable of getting at the meaningful aspects of social life. In other say, quantitative research can generalize a representative result but sometimes too superficial.

Level of measurement

Furthermore, there is strength of quantitative research about the measurement quality of variables. Babbie (2007) noted that quantitative research is strong on reliability and weak on validity compare to qualitative research. Actually, quantitative research has a standardized stimulus that goes a long way eliminating unreliability that made by observers in qualitative research (Babbie 2007). However, qualitative field research is weak on reliability. Field research has problem on observing, such as doing research about the homosexuality, bias from those researchers or observers may within the process. As it is very personal and difficult of controlling researchers' bias, as well as their misinterpretation, the judgment on observation might have considerable reliability problem.

Nevertheless, qualitative research has distinctive strength when concerning the validity. Babbie (2007) noted that field research provides measure with greater validity than do survey and experimental measurement. For instance, when they are interested in investigating the attitudes and feeling of sex offenders in natural setting, then observation method would be more valid than doing survey for investigating and understand the situation. Contrarily, survey may not be more valid as some of the respondents' feeling and attitudes may not be answered in the self-administered questionnaires (Babbie 2007). For example, questionnaires may take forms of 'strongly agreeing, agreeing, disagreeing, or strongly disagreeing', but without 'neutral'. Thus the result can be manipulated and weak in measuring the real situation validly.

Representativeness of the data result

For making the result of representative research, quantitative research seems more strengthen than qualitative research. Representativeness is that the quality of a sample of having the same distribution of characteristic through random selection (Babbie 2007). It adopts the probability sampling method such as to collects a wide range of data through random selection. For example, when doing a survey about the citizens' satisfaction about Hong Kong SAR Policy Address of 'My Home Purchase Plan', simple random sampling can be used which each of population has equal chance to be selected. In this way, the result can be generated.

However, qualitative research is comparatively lack of representative due to non random sample selection and smaller sample sizes. For example, there is a study about Hong Kong citizens' attitudes toward the new legislation of Minimum Wage, qualitative in-depth interview by using purposive sampling with smaller sampling sizes. If researchers choose sample for in-depth interview with many of employers rather than employees, it may not represent the population as researchers' bias may involve.


Quantitative research and qualitative research both have strengths weaknesses in different aspects. Qualitative research is strengthen on the flexibility of research design, detailed information about real social life, and level of measurement on validity while quantitative research may has strength on the systematic procedure of data collection, level of measurement on reliability, and representativeness of data result.

Total words: 1090