Quantitative data is data in a numerical form- in the form of numbers. Qualitative data spans a range of material from the descriptions of social life provided by participant observation and unstructured interviews to information from written sources.
'Interviewer bias' is unavoidable; the interviewer will undoubtedly affect the responses of the interviewee. The interviewer has particular personality traits, e.g. aggressive/passive; they also have particularly social characteristics, e.g. race, gender, age group and social class. The social and psychological characteristics will be received and recognised in certain ways by the interviewee, and undoubtedly have an effect on their responses. Qualitative data is not objective; the researcher has to adopt the values of the subjects, which will affect the data collected. One of the most popular methods is participant observation, also connected is when a researcher 'goes native'. By temporarily becoming or by pretending to become members of the group being studied it is easier to provide an accurate description of social life for that particular subject, unfortunately this includes adopting the values of the subject too, making the research void of objectivity.
Quantitative research methods are more reliable than qualitative research methods, because quantitative data usually consists of official statistics, gathered and averaged among many mathematicians where as qualitative research relies heavily upon the validity of the researcher, as essentially it is the researchers experiences which influence his/her results.
Various other advantages to quantitative research methods include; Easy to interpret, the results are written in numerical or statistical forms, thus interpretation isn't difficult. This approach is favoured by positivists, because of its scientifically natured methods. With
The disadvantages to quantitative data are; the research fails to give an in-depth picture compared to qualitative data, which is rich with description. Qualitative data can be unreliable (see Durkheim's study of suicide). The research methods can induce the researcher to manipulate the 'subjects' answers to suit the research.
From the above conclusions could be drawn as to which type of research methods or more capable of the job in hand, but depending on the need for the research then each research methods purpose can increase/decrease. E.g. - to get a picture of social life - qualitative data, to get data about social life - quantitative. From my findings I have found that there are more advantages than disadvantages, although this doesn't make it 'better' against qualitative, it is merely 'better' at the specific task it performs.