Meadows quant res dese

Uploaded on


  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads


Total Views
On Slideshare
From Embeds
Number of Embeds



Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

    No notes for slide


  • 1. Quantitative Research Design Ken N. Meadows, Ph.D. Educational Researcher Teaching and Learning Services
  • 2. Outline Defining quantitative research design Non-Experimental designs  Descriptive  Correlational Experimental designs  Experiments  Quasi-experiments Conclusions… 2
  • 3. Definitions Research design: the framework used to conduct the research Research method: data collection techniques (e.g., document analysis, interview, survey) 3
  • 4. Definitions Quantitative research2,6: Assumptions:  Reality - objective & singular  Researcher - independent from research  Research - value-free, unbiased  Research process – deductive (generate hypotheses from theory), emphasize cause/effect, isolation of variables, context-free, prediction, generalizability 4
  • 5. Definitions Quantitative research2,6: Methods: larger scale (e.g., survey) Data: quantitative (numbers) Analysis: statistical 5
  • 6. Definitions Qualitative research2,6: Assumptions:  Reality – subjective & multiple (from participants’ perspective)  Researcher – interacts with research  Research – value-laden, biased  Research process – inductive (generate theory from data), emergent variables (identified during research), patterns identified 6
  • 7. Definitions Qualitative research2,6: Methods: smaller scale (e.g., interviews) Data: qualitative (words) Analysis: thematic 7
  • 8. Definitions Two broad categories of quantitative designs:  Non-experimental  Experimental A major difference - validity of the designs7  Internal validity: extent design can identify causal relationships & rule out alternate explanations of relationships between variables  External validity: extent design allows conclusions to generalize beyond the confines of study 8
  • 9. Definitions  Non-experimental designs tend to be low in internal validity but higher in external validity  Experimental designs tend to be high in internal validity but lower in external validity 9
  • 10. Non-experimental Non-experimental designs:  Descriptive  Correlational Descriptive designs5,7 - identify the characteristics of a phenomenon Describe the variable under investigation – not examine relationships among variables For example: LARSN needs assessment (Hoffman, Meadows, & Martin-Gardiner, 2009) 10
  • 11. Non-experimental Correlational designs examine relationships among variables under investigation1,5,7 Tend to examine relationships as they exist Do not isolate & manipulate variables to establish causal relationships as in experimental research 11
  • 12. Non-experimental For example, Eron, Huesmann, Lefkowitz, & Walder (1972) examined relationship between preferences for violent television & aggressive behaviour 12
  • 13. Non-experimental Cannot make causal statements with correlational research1,5,7  Directionality problem (if X <-> Y, does X ->Y or Y ->X)  Third variable problem (if X <-> Y, possible X<-Z->Y) 13
  • 14. Non-experimental More complex correlational designs can suggest direction of causality E.g., Cross-lagged panel correlation design Eron and colleagues (1972) – collected data at grade 3 &13 and correlated variables between years – found moderate correlation between grade 3 preference for violent tv & grade 13 aggressive behaviour 14
  • 15. Non-experimental In groups of 3, please discuss:  Research question you would be interested in researching  Design of your research (i.e., descriptive or correlational)   Data sources for that project  Research methods you would use 15
  • 16. Experimental Experimental designs:  Experimental  Quasi-experimental Experiment1,3,5,7 - variable is systematically manipulated (independent variable; IV) to observe effect of manipulation on another variable (dependent variable; DV) 16
  • 17. Experimental Experimental control1,3,5,7 – hold extraneous variables constant in experiment to isolate effect of IV on DV For example, Hopkins & Wilson (2009) 17
  • 18. Experimental Common experimental design: pre-test/post-test control group design1,3,5,7 Measure Exposure Measure Before AfterTreatment 01 X 02GroupControl Group 03 04 18
  • 19. Experimental If change from pre- to post-test for treatment group & not control group (or not as much), change can be attributed to the treatment (assuming proper experimental controls) Controlling for extraneous variables1,3,5,7:  Participant differences: random assignment of participants to treatment and control groups or matching  Situational differences: hold situations constant 19
  • 20. Experimental Pre-test/Post-test Control Group7 – possible pre- test influences treatment (threat to external validity) Post-test only control design7: Exposure Measure After Treatment X 01 Group Control Group 02 20
  • 21. Experimental Post-test only control group – groups should be same on DV before treatment because of random assignment Other threats to external validity for experiments8:  Interaction effect of selection bias and treatment  Reactive effects of the experiment 21
  • 22. Experimental Quasi-experimental designs5,8: not true experiments because the groups tend to be naturally occurring not groups created by researcher Try to match participants and control for situational variables as much as possible 22
  • 23. Experimental Common quasi-experimental design: pre-test/post- test non-equivalent group design8 Measure Exposure Measure Before AfterTreatment 01 X 02GroupControl Group 03 04 23
  • 24. Experimental Example: Haffie, Meadows, Dunn, & Graves (2009) quasi-experimental research higher in external validity than experiments (reflect real life more) but weaker in internal validity than experiments (do not control for all extraneous variables) 8 24
  • 25. Experimental In groups of 3, please discuss:  New research question you would be interested in researching  Design of your research (i.e., experimental or quasi- experimental)   Data sources for that project  Research methods you would use 25
  • 26. Questions, comments… 26
  • 27. References1. Bordens, K. S. & Abbott, B. B. (2008). Research design and methods: A process approach (7th ed.). Boston: McGraw-Hill.2. Creswell, J. W. (1994). Research design: Qualitative and quantitative approaches. Thousand Oaks, CA: Sage Publications.3. Elmes, D. G., Kantowitz, B. H., Roediger III, H. L. (1999). Research methods in psychology (6th ed.). Pacific Grove, CA: Brooks/Cole Publishing Company.4. Eron, L. D., Huesmann, L. R., Lefkowitz, M. M. & Walder, L. O. (1972). Does television violence cause aggression? American Psychologist, 27, 253-263. 27
  • 28. References5. Leedy, P. D., & Ormrod, J. E. (2001). Practical research: Planning and design (7th ed.). Upper Saddle River, N.J.: Merrill Prentice Hall.6. OLeary, Z. (2004). The essential guide to doing research. London: Sage.7. Powell, R. R., & Connaway, L. S. (2004). Basic research methods for librarians (4th ed.). Westport, Conn.: Libraries Unlimited. 28