URBP 204 A Class 9 Note: the class notes summarize Salkind (2004) Chapters 12, 13 and 15 CLASS 9 Correlation Coefficient Tutorial 3 Give back Rev Ex Set 1 and Neighborhood Profile Memo Survey Research CLASS 10 Probability- based Sampling Survey Research Experiments (Time Permitting) Qualitative Field Research (Time Permitting) Introduce Mid-Term Introduce Exercise Set 3 Factorial ANOVA Example Lab-Time for Term Project

Types of probability sampling designs Simple random sampling All elements are numbered and then a predetermined number are randomly selected. (may get clusters, should know the entire population) Systematic sampling Every k th element chosen For e.g.: every 10 th house; danger of biases (every 10 th house may be a corner house - traffic noise) Stratified Sampling Reduce sampling error by less variability e.g. single-family houses and apartments Within the strata we may employ simple random or systematic sampling Multistage clustering sampling Sampling of clusters City-wide study - list census tracts - choose sample of census tracts - list all block groups - choose sample of block groups - list all blocks - choose sample of blocks - list all h.h.s - choose sample of h.h.s May also stratify the sample: Stratification in multistage cluster sampling Note: the class notes summarize Babbie (2004) Chapter 7, and part of Chapter 9.

Survey Research Guidelines for asking questions Open ended vs close ended question Open ended – more rich; coding difficult; more chances of error while recording Close ended – less rich; responses may be straight jacketed; less chances of recording error; careful about exhaustiveness Make items clear - income last year – based on W-2? Avoid double-barreled questions – Should San Jose cut back on road construction and increase allocation for affordable housing? Respondent must be competent and willing to answer Questions should be relevant Keep it short Note: the class notes summarize Babbie (2004) Chapter 7, and part of Chapter 9.

Guidelines for asking questions contd…. Avoid negative terms – do you think we should not do this? Avoid biased items and terms – do you agree with the recent health reports’ finding that…… Note: the class notes summarize Babbie (2004) Chapter 7, and part of Chapter 9.

Guidelines for survey interviewing Modest yet neat appearance Avoid voice inflections Be neutral Be polite Be familiar with the questions Don’t add your words to the question Record responses exactly Gently probe for responses/ clarifications Note: the class notes summarize Babbie (2004) Chapter 7, and part of Chapter 9.

Questionnaire Construction Not cluttered Professional look; clear instructions on how to choose responses (especially if self-administered), Use of contingency questions Use of matrix format Order of questions – bias due to the order (negative aspects of sprawl; then ask is sprawl bad); in self- administered begin with interesting questions; in interviews – uncomplicated questions first Include clear instructions and introductory statements (now think about the last one week….) Pretest the questionnaire

Self- administered Questionnaire Mail; home delivery or combination; questionnaire at a public gathering; etc. If mail delivery Monitor the return Follow up mailings Telephone Surveys Unlisted number – random digit dialing Advantages – cheap and quick; no dress code; probe more sensitive areas; more quality control possible as central location; safety. Disadvantages – compete with bogus surveys; easy to hang up; answering machines; cell phones

Comparison of self-administered and interview survey methods Advantages of self- administered over face-to-face interviews Cheaper More geographically extensive Require smaller staff Easy to probe sensitive topics Advantages of face-to-face interviews over self- administered questionnaires Larger response rate More effective for complicated issues May also note other information - condition of the neighborhood, etc.

Strengths and weaknesses of survey research Strengths Describe characteristics of a large population Make large samples feasible More flexible – can cover several topics Strong on reliability Weakness Have to ascribe the same intent to responses to questions related to complex concepts Least common denominator – superficial in coverage of complex topics Life situation/ context not known Can not change questions mid-way Respondent may form opinion at the moment Weak on validity

MODES OF OBSERVATION Experiments Surveys Qualitative Field Research Others ( for example, content analysis)

EXPERIMENTS Taking action Observing consequences of the action Suited to : a) Research “well-defined concepts and propositions” (Babbie 221) b) Explanatory studies c) Small groups Can be: Laboratory experiments (health sciences, physical sciences, etc.) Natural experiments (naturally occurring events)

Components of a classical experiment a)Dependent and independent variables b)Pretesting and posttesting c)Experimental and control groups Effect of knowledge of good examples of high density development on the people’s perception about density Selecting subjects Randomization Matching (Income, urban vs rural, race, etc.) - like quota sampling Combination of both, akin to stratified sampling

Variations in Experimental Design Preexperimental research designs One shot case study – no pretest – just show examples of good high density developments and then measure the perception One- group pretest- posttest design – no control group – not sure whether examples caused the effect Static-group comparison – no pretest; control group present- randomization of subjects important (examples of good high density development showed to one group and not to the other)

Validity Issues in Experimental Research Internal validity issues- does the conclusion reflect the process? History – major event during the experiment Maturation – people old, tired, sleepy. Slept while shown examples of high density development! Testing – testing and retesting affects subjects’ responses Instrumentation- pretest and posttest measures different Statistical regression- extreme positions undesirable as these people are likely to improve anyways Selection biases – groups should be comparable Experimental mortality – bias due to subjects leaving Causal time order – dependent variable causes changes in the stimulus – e.g. rat causes change in virus; Diffusion of treatments- experimental and control groups in communication Compensation – to the control group. Thus they are no longer ideal control group. Compensatory rivalry – extra efforts by the control group Demoralization – of the control group

External Validity Issues in Experimental Research Is the experiment generalizable? What if instead of slides of good high density development we showed a film? Natural experiments Natural events as stimulus- e.g. hurricanes, bombings, etc. Some of the Limitations: Comparable control groups difficult to find Selection of subjects not random

Strengths and Weaknesses of the Experimental Method Strengths Replication is easy – more reliability Interaction of dependent and independent variable easy to isolate Weaknesses Artificiality- changes may not occur in more natural settings

Qualitative Field Research Topics appropriate for Field Research Hard to quantify Nuances Important to observe in natural settings Social processes over time Study of relationships, roles, groups, subcultures, lifestyles, etc. Special Role of Observers Complete observer – does not participate at all. Less appreciation of what is being studied. Complete participant – full participation – genuine or pretend; for subjects not a researcher. Issue of deception; affecting the study; going native! Somewhere in between- participate but let the subjects know that you are a researcher

Relations to subject Pretend to join or really join - adopt the subjects’ point of view or view them critically- or combination The setting can have an impact – e.g. homeless on the streets, welfare office, or shelter Swayed by subjects’ personal lives (problems, etc.) - threat of loosing scientific objectivity Notion of superiority over the subjects

Strengths and Weaknesses of Qualitative Field Research Strengths Not superficial Flexibility- research design; begin the observation Can be inexpensive Greater validity than survey and experimental design Weaknesses Can’t statistically describe a large population Not good at predicting future Less reliability than the survey and experimental design