Alan Bradley

Alan.Bradley@warwick.ac.uk

Alan.Bardely

Researching society and culture

Week 5 Quantitative methods (2)

Lecture Outline

• A brief recap of some terms from last week

• Types of quantitative research

• Surveys and questionnaires

• Samples and pilot studies

• Measuring concepts and indicators

• Analysing quantitative data

Some terms from last week

• 1) Representativeness – relates to sample• 2) Replication• 3) Validity • Internal:- Are causal relationships valid?• External:- are results generalisable?• 4) Reliability – consistency of measures of

concept• More on all of this as we go through the

lecture

Types of quantitative research

• 1) Primary data – examples are surveys and questionnaires, structured interviews, content analysis.

• 2) Secondary data – a) collected by other researchers or: b) collected by institutions.

• The focus in this lecture will be on surveys/questionnaires

The process in surveys/questionnaires

• 1) Theory and hypothesis• 2) Research question(s)• 3) Research design – methods etc• 4) Choosing sample – issues raised last week• 5) Questionnaire – open/closed question, self completed,

mail or face to face, interviewers• 6) Pilot study• 7) Data collection• 8) Data analysis • All of this is an ‘ideal type’

Sampling and Pilot study

• Sample aims to represent the whole population (remember last week)

• Pilot study to check that questions can be understood, no ambiguity, tests the design of the research.

Measuring concepts

• Some concepts relatively easy to measure, eg sex/gender?

• Others may be more problematic, eg social class, social mobility, poverty

• ‘Measurement (of concepts) provides the basis for more precise estimates of the degree of relationship between concepts’

• (Bryman, A. 2008: p144)

Indicators of concepts

• Measures are quantities (eg household income)

• Indicators are concepts which allow us to quantify non-quantifiable concepts

• That is, indicators are used as if they are concepts.

• What indicators may allow us to measure social class, poverty, attitudes?

Indicators of social class

• Employment status commonly used:• 1) Higher management• 2) Lower management• 3) Intermediate occupations• 4) Small employers/self-employed• 5) Lower supervisory/lower technical occupations• 6) Semi routine occupations • 7) Routine occupations• National Statistics Socio-economic Classification• Think what other indicators could be used.

Analysing quantitative data

• Univariate - frequency tables/central tendency. Example to follow.

• Bivariate – eg gender and educational attainment

• Multivariate – computer analysis needed

• 2 and 3 raise issues of correlation versus cause and effect

Univariate analysis

• Usually frequency tables showing the number of instances occurring, and the % of the whole.

• May include grouped variables:-• Age 20 and under

21-30

31-40

41-50

51 and over Why these intervals?

Univariate analysis (2)

• Measures of central tendency (Averages)

• Mean - total divided by number in group

• Mode - figure that appears most often

• Median – in the middle, ie the same number above as below

Example of central tendency

• Annual income in £ 1) 5,000

2) 7,000

3) 20,000

4) 20,000

5) 30,000

6) 50,000

7) 200,000• Calculate mean, mode and median incomes

Answers

• Mean = 47,430

• Mode = 20,000

• Median = 20,000

• How useful are these?

Measures of dispersion

• Range in previous example is:-

• 5,000 to 200,000

• Thus, many of the instances vary widely form the average.

• Standard deviation measures the average amount of variation from the mean.

• Issues of validity etc

• Calculations carried out by computer (SPSS)

Suggested readings

• Bryman, A. 2008 Chapter 8 (The nature of quantitative research)

• and Chapter 14, just the bit on uni/bivariate analysis

• OR:- search in any methods textbook for chapters on quantitative data collection and analysis!

Next week

• Qualitative research - interviews