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August
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- Discussion Card for Creswell's Ch. 1
- Discussion Card for Creswell's Ch. 2
- Discussion Card for Creswell's Ch. 3
- Discussion Card for Creswell's Ch. 4
- Discussion Card for Creswell's Ch. 5
- Discussion Card for Creswell's Ch. 6
- Discussion Card for Creswell's Ch. 7
- Discussion Card for Creswell's Ch. 8
- Discussion Card for Creswell's Ch. 9
- Discussion Card for Creswell's Ch. 10
- Discussion Card for Creswell's Ch. 11
- Discussion Card for Creswell's Ch. 12
- Discussion Card for Creswell's Ch. 13
- Discussion Card for Creswell's Ch. 14
- Discussion Card for Creswell's Ch. 15
- Discussion Card for Creswell's Ch. 16
- Discussion Card for Creswell's Ch. 17
- Discussion Card for Creswell's Ch. 18
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August
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Question: When using true experiments, is it ethical to give one group "experimental" treatment, while withholding treatment from the other group, especially regarding promising health or educational benefits? (p.313)
ReplyDeleteQuote: (p.326) "In deciding what intervention to use (in an experimental design)..the researcher should select an intervention of adequate "dosage" (Lipsey, 1998). This means that the intervention must last long enough and be strong enough to actually have an impact on the outcome."
Fact: Experimental research designs appeal to the scientist in me. In true experiments, the researcher randomly assigns participants to different conditions of the experimental variable. True experiments comprise the most rigorous and strong designs for research because of equating the groups through random assignment.(p. 313)
Important Fact: page 300 "The random assignment of individuals to groups (or conditions within a group) distinguishes a rigorous, "true" experiment from an adequate."
ReplyDeletepage 301 - Don't confuse random assignment with random selection. They serve different purposes and both important to quantitative research.
Question: Page 308: Even though participants selected mature and develop similarly. Even then won't the maturation of those individuals affect the/alter the experiment?
Quote: Page 313 In regards to Quasi-Experiments I have selected the following quote. "Randomly assigning students to the two groups would disrupt classroom learning." "Introduces considerably more threats to internal validity than the true experiment. Because the investigator does not randomly assign participants to groups the potential threats of maturation, selection, mortality, and the interaction of selection with other threats are possibilities."
Barbara- Fabulous question! I would feel like I was not doing my job as an educator if I were to withhold something from my 6th grade students which could assist in their education.
ReplyDeleteBarbara - In regards to your comment. Prescribed teaching! Prescribed tutoring! Just the right amount of support to assist the students in the learning process in order to help them become independent life long learners.
ReplyDeleteBarbara - I find it interesting how our posts in response to our reading are so similar. Kind of made me chuckle a bit! I really enjoyed your quote!
ReplyDeleteBarb,
ReplyDeleteGreat question. I have the same one. As a teacher, I find it unethical to withhold interventions that I believe would be helpful to my students. Creswell said that some researchers offer the intervention to the control group after the experiment is over for this reason.
Fact: Random selection and random assignment are both important to quantitative research. Although, random selection is often not used in experiments for logistical reasons.
ReplyDeleteQuestion: I have to admit, the section on covariates baffles me. Normally I enjoy diagrams, but I'm not getting Figure 11.1. What?
Quote: "When you design an experimental study, use the six characteristics as major featues of your "Methods" discussion: random assignment, control over extraneous variables, manipulation of the treatment conditions, outcomes, measures, comprison groups, and threats to validity.
Question: Is randomly selecting participants going against the IRB process? page 301
ReplyDeleteInteresting Quote: In some experimental situations, it is not enough to know the effect of a single treatment on an outcome; several treastments may, in fact, provide a better explaination for the outcome. Page 315
Interesting Fact: Key ideas to experimental research is random assignment, control over extraneous variables, manipulation of the treatment conditions, outcome measures, group comparisons, and threats to validity. Page 300
Quote: "All experiments have some random error (where the scores do not reflect the "true" scores of the population) that you cannot control, but you can try to control extraneous factors as much as possible." (p. 301)
ReplyDeleteQuestion: What does figure 11.5 on p. 317 explain exactly?
Fact: Ideas used in experiments today were mostly in place by the first few decades of the 20th centry.
Corey Nickell
ReplyDeleteQuestion: (Page 300) Will all 6 of the experiment’s characteristics show up in every experiment?
Quote: (Pg 308) Threats to internal validity. “Of all the threats to the validity, these are the most severe because they can compromise an otherwise good experiment.”
Interesting fact: Creswell recommends following the eight-step process as a general guide for procedures when designing and conducting an experiment. I love that there is a guide…I am assuming that this guide is not set in stone and that it may have to be tweaked if necessary.
LaDawndra
ReplyDeleteQuestion:
How do you test a design before you use it for research? I wonder if this means you experiment on a seperate group before conducting the experiment on others?
Quote:
"In most experimental research , the statistical test of choice is a group comparison statistic such as t-test, analysis of variance, or analysis of covariance." p314. This sound so familiar from most previous statistic classes. I find it intersting how ANOVA and the t-test can show the similarities or differences between two sets of data.
FACT:
Research designs have been around for many decades however the design of them have improved over time making a reseracher's task easier.
LaDawndra,
ReplyDeleteYou do a pilot study if you can. That will help you before your actual study.
Good job,
Dr. Hendrix
Question: My question goes along with Ann Dotson's facts about random assignment and random selection. I admit I had to read this section twice and am still not sure I completely understand the difference. Is random assignment truly random if you have to "equally distribute any variability of individuals"?
ReplyDeleteQuote: "The most frequently used designs in education are those where the researcher compares two or more groups."
Fact: When attitudinal or achievement tests are used as pretests, the scores may also affect posttest scores because participants can anticipate the questions on the posttest based on their experiences with the pretest. pg 302.
Ann Dotson also mention accounting for maturation. When reading that section, I wondered how does one estimate changes in maturity so as to remove them statistically?
Quote:"In an experiment, the researcher physically intervenes in one or more condition so that individuals experience something different in the experimental conditions than in the control condition." (pg 305)
ReplyDeleteQuestion:Based on the quote above, Is the researcher guiding the outcome of the experiment? Or just guiding toward the question posed?
Fact:Outcome measures also need to be valid so that experimental researchers can draw valid inferences from them. I think I just answered my own question.