- First we divide the pop by certain characteristics
- based on key independent variables
- each sub-population is called stratum
- Each stratum is mutually exclusive set of elements
- finally using SRS or SS, we sample from each stratum
- Used to examine the r/ship b/n independent (criteria for stratification) and dependent variable;
- To make comparisons among sub-pop
- And used to reduce sampling error
- * prior information about the pop is required
- Disproportionate Stratified Sampling- equal sample size from each stratum
- Proportionate Stratified Sampling - proportional sample size from each stratum
- Note: Use SS only if there is significant difference across the strata
Multi-Stage Cluster Sampling
- For population without exhaustive list (SF)
- Or when it is impossible to compile a complete list of the elements (SF)
- Involves sampling of natural clusters
- Eg. Schools, kebeles, industries, etc
- Followed by selection of elements from the clusters using SRS or SS
- Eg. Addis Ababa households’ mode of transportation
- Involves listing and sampling at d/t stage
- It involves two or more sampling error
Stratified Multi-stage Cluster Sampling
- Involves grouping of clusters with similar characteristics;
- Then selecting clusters from each group of similar clusters;
- Eg. Lideta Sub-city poverty study
- Stratification can take place at each stage of sampling
Probability Proportionate to Size (PPS) Sampling
- In most cluster sampling small clusters tend to disproportionately represented
- To avoid this we give equal chance of selection
- Giving each cluster chance of selection proportionate to its size
- Then selecting equal sample size from each cluster
- Illustration: suppose we want to sample 1/10 th of 5 clusters, in which the clusters have 50,100, 200, 300 and 400
- We will give a proportion of 1, 2, 4, 6 and 8 respectively
- Permit selection of more clusters
- Ensure representation of large clusters
- Equal chance of being selection to the pop
- PPS is applied under 3 conditions:
- When dealing with unevenly distributed clusters;
- With large sample size w/c can be broken into clusters; and
- When we have data on the proportion of each cluster.
- heterogeneity of the pop, strata or cluster;
- The larger the sample size the the lower the sampling error
- Purposive or judgmental sampling: Sample selected because of their unique position in the pop understudy;
- Quota Sampling : selected to represent a certain characteristics or group in a pop.
Measurement and Meaning
- Concept : is a mental image that summarize similar observations, idea,
- Conceptual Definition : specification of the meaning of each concept in a research to enable measurement
- Eg. Slum is ‘a heavily populated urban
- area characterized by substandard housing and squalor’.
- Operational Definition: a definition by which we make the concept measurable, using indicators.
- Eg. Slum- • inadequate access to safe water;
- • inadequate access to sanitation and other infrastructure;
- • poor structural quality of housing;
- • insecure residential status.
Level of Measurement
- There are 4 levels to measure variables.
- Nominal Variable : mutually exclusive categories. With no ordering.
- Eg. Sex, marital status, etc
- Ordinal Variable : categories ordered or ranked in sequential manner.
- Eg. Class rank, social class
- Interval-Ratio Variable: logical, ordered and defined in terms of a standard unit of
- Usually have a zero point- i.e. absence
- Eg. Age, land area, distance from city-center etc
- Discrete variable- integer number of values
- Continuous Variable- assume a decimal number of values. Eg. Distance, area, etc
- Note: the statistical analysis that we apply differs to each level of measurement and to the two types of variables.
- Questionnaires are set of questions or statements which we used to gather data in survey research.
- There are two types of questions
- Open-ended- respondent gives his own answer
- Eg. What is your attitude towards Addis trans?
- Close-ended- respondents selects from the choices provided
- Eg. How do you grade urban trans in Addis
Guide to Question Construction
- Respondents must be competent to answer
- Eg. What kind of planning technique should AACA apply?
- Use vocabulary that respondents can understand.
- Eg . What issues should be considered in urban
- Make items clear- avoid ambiguous questions.
- Eg. Do you live near Mekato?
- How often do you visit a doctor?
- Avoid Negative Items- respondents might agree with the –ve one while they mean +ve one.
- Eg. Should not the AACA invest on infrastructure development?
- Avoid Double Barreled Questions- two questions in one question
- Eg. What is your opinion about the urban policy and its implementation in Ethiopia?
- Format questions in a sequential order and bring together similar questions
- Eg. SD, Mig. History, family condition, living condition and finally empl’t condition
- Avoid biased items or labels
- Eg. Fascist, racist, fundamentalist, etc
- Contingent questions should be asked to the relevant respondents.
- If yes, does your spouse have a job?
- The purpose of the research should have to be clearly indicated in the beginning of the questionnaire
- General and specific instruction of the questionnaire should have to be clearly indicated
- There are two types of questionnaires
- Self-administered – filled by the respondent him/herself;
- Enumerator administered- filled by an interviewer.
Other methods of data collection
- Sample survey enables us to collect data from large amount of respondents using a representative sample
- But its broad coverage make to gather shallow data.
- When we want to collect in-depth information we use:
- Focus group Discussion; and other methods
- Used to collect detailed information using semi-structured interview guide
- The guide is set of generic open ended questions and probing questions
- The guide only lead the flow of the interview
- Probing is basic tool in this method
- Eg. What do you know about low cost housing?
- LCH vis-à-vis affordability
- Interviewee is given freedom of expression in his own words
- Enable to collect depth information on our research topic
- Usually used with experts, officials, knowledgeable community members, etc
- Taking note and recording the interview is crucial
- Heavily influenced by the interviewer skill; and
- Difficult to compare responses in a rigorous way.
Focus Group Discussion
- Used to gather information from a discussion of a group by giving them a topic of discussion
- Group interaction b/n respondents will stimulate richer responses
- The interviewer can observe the discussion and understand their feeling, behaviors, attitudes, etc
- Usually have 6-12 members and a moderator, but a group size of 8 is preferable
- The moderator is expected only to raise topic of discussion and facilitate the discussion
- The group should be a homogeneous group and it is better if they are acquainted
- If the FGD is handled by a skilled moderator it enables to generate detailed and valid data
- The moderator should control the flow of the discussion using a checklist
- In FGD also probing is important
- And the moderator has to take note and use a tape recorder
The Research Paper
- Finding and narrowing the Problem
- Select the general topic or issue of research (from the literature or from our experience);
- Review the evidence or literature review
- Identify the knowledge gap
- then we make the research problem precise
- every research report should have to clearly state the research problem in the beginning
- Research problem is the k’ge gap to be filled by the research not social problem
2. Formulating Research Questions
- This are question that the research is going to address
- After clearly setting the RP, we will split the RP into specific answerable research questions
- Eg. RP- the K. 10 housing condition
- How is the structural conditions of the houses in the kebele?
- What services and amenities does the residents receive?
- How is the provision of basic infrastructure in the kebele?
3. Composing the Paper
- Academic research report should have to be organized in a manner
- Introduction-literature review-methods-result-conclusion-recommendation
- Introduction - describes related research and explains what your work contributes and why it is important.
- It sketches out the objectives, research questions, hypothesis, scope and organization of the report.
- b) Literature Review - presents the summary of theoretical and empirical findings related with the research topic
- c) Methods - this section describes each steps that the study applied in collecting and analyzing the data.
- it presents the methodology used, the survey design, the sampling technique applied, the sample size, the composition of the sample and methods of data analysis.
- In addition, the characteristics of the population is described.
- Result - should summarize the data and the inferences drawn
- It should have to answer the research questions raised in the introduction
- It should include tables and figures to explain the variables understudy
- The result section should be sub-divided into sub-topics and arranged in an organized manner
- The result should critically analyzed using other evidences and theories
- Draw the conclusion from your findings and discuss the possible significance of your findings (recommendation)
- And indicate areas of further research
- The research report should be readable, therefore we should have to make proper editing work before submitting the report.
- Word Choice - avoid undefined adjectives.
- Eg. Deep, wonderful, near, many, little
- Logical connection with sentences - there should be a logical flow of sentences in a paragraph.
- - There should have to be coherence b/n sentences.
- Avoid to be & passive voice - verb to be (is, was, were, will be) and passive voice makes our description static.
- Avoid informal language - conveying our finding in an informal language makes to seem thoughtless.
- Eg. Really was not upset, didn’t, ain’t, all of a sudden etc
- Keep your summary, paraphrase and quotation as short as possible and harmonize the quote into your paper
- Every works quoted or paraphrased from other sources should be properly cited.
- We use in-text citation (the new MLA) method.
- Eg. Modern urban planning has arisen in response to social and econ problems (Neil 56) or
- We can also use Author-Date system
- Eg. Modern urban … (Neil, 2004:56) or
- According to Neil … (2004:56)
- You should have to enlist every material you used in the bibliography section.
- Neil, William J.V. (2004) Urban planning and Cultural Identity. London: Routledge
- Morello, Jorge (2000)’Urbanization and Ecology’ . In Third World Planning Review , Vol. 22 No. 4, 2000, pp 119-132