Please post your question, quote, and fact here for chapter 11. Also, respond to at least two of your peers' posts as well as my questions here.
Questions:
1.) Define the purpose of an experiment and when you would use this design.
2.) Why do researchers use random assignments in experiments?
3.) Describe the types of procedures used to control extraneous factors in an experiment.
4.) Describe how researchers manipulate the treatment condition.
5.) Define "outcome variable."
6.) Explain how researchers compare groups in an experiment.
7.) What are some internal and external threats to validity in an experiment?
8.) Describe between-group and within-group experiments.
9.) List the steps in conducting an experimental study.
10.) List the criteria for evaluating an experimental study.
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Question: Can experiments grow to be too sophisticated & complex because of technology and impoved statistical procedures?
ReplyDeleteQuote: Experimental research began in the late 19th and early 20th centuries, with psychological experiments."
Fact: There are several key ideas central to experimental research:
random assignment
control over extraneous variables
manipulation of the treatment conditions
outcome measures
group comparisons
threats to validity
1. In an experiment, you test an idea to determine whether it influences an outcome or dependent variable. You use an experiment when you want to establish possible cause and effect between your independent and dependent variables.
ReplyDelete2. Random assignment is the process of assigning individuals at random to groups or to different groups in an experiment. Equating the groups means that the researcher randomly assigns individuals to groups and equally distributes any variablility of individuals between or among the groups or conditions in the experiment. By systematically distributing this potential error among groups, the researcher theoretically distributes the bias randomly.
3. Random assignment is a decision made by the investigator before the experiment begins. Other control procedures you can use both before and during the experiment are pretests, covariates, matching of participants, homogeneous samples, and blocking variables. A posttest is a measure that is assessed for participants in an experiment after a treatment.
ReplyDelete3. A pretest provides a measure on some attribute or characteristic that you assess for participants in an experiment before they receive a treatment. Covariates are variables that the researcher controls for using statistics and that relate to the dependent variable but that do not relate to the independent variable. Matching is the process of identifying one or more personal characteristics that influence the outcome and assigning individuals with that characteristic equally to the experimental and control groups.
ReplyDeleteChoose homogeneous samples by selecting people who vary little in their personal characteristics. A blocking variable is a variable the researcher controls before the experiment starts by dividing the participants into subgroups and analyzing the impact of each subgroup on the outcome.
4. The researcher physically intervenes or manipulates with interventions in one or more condition so that individuals experience something different in the experimental conditions than in the control condition. This means that to conduct an experiment, you need to be able to manipulate at least one condition of an independent variable. Experimental researchers manipulate or intervene with one or more conditions of a treatment variable.
ReplyDelete5. The outcome is the dependent variable that is the presumed effect of the treatment variable. It is also the effect predicted in a hypothesis in the cause-and-effect equation. Examples might be
ReplyDeleteachievement scores on a criterion-referenced test
test scores on an aptitude test
6. A group comparison is the process of a researcher obtaining scores for individuals or groups on the dependent variable and comparing the means and variance both within the group and between the groups.
ReplyDelete7. Some threats to internal validity are 3. 1.Threats related to participants in the study are: history, maturation, regression, selection, mortality, interactions with selection.
ReplyDelete2.Some threats related to treatments are: diffusion of treatments, compensatory equalization, compensatory rivalry, resentful demoralization.
3.Some threats related to procedures are: testing and instrumentation.
Some threats to external validity:
1. interaction of selection and treatment
2. interaction of setting and treatment
3. interaction of history and treatment
8. Between-Group Designs
ReplyDelete1. true experiments
2. quasi-experiments
3. factorial designs
Within-Group or Individual Designs
1. time series experiments
2. repeated measures experiments
3. single-subject experiments
8. In true experiments the researcher randomly assigns participants to different conditions of the experimental variable.
ReplyDeleteQuasi-experiments include assignment, but not random assignment of participants to groups.
Factorial designs represent a modification of the between-group design in which the researcher studies two, or more categorical, independent variables, each examined at two or more levels.
A time series design consists of studying one group, over time, with multiple pretest and posttest measures or observations made by the researcher.
In a repeated measures design, all participants in a single group participate in all experimental treatments, with each group becoming its own control.
Single-subject research involves the study of single individuals, their observation over a baseline period, and the administration of an intervention.
9.
ReplyDeletestep 1. Decide if an experiment addresses your research problem.
step 2. Form hypotheses to test cause-and-effect relationships.
step 3. Select an experimental unit and identify study participants.
step 4. Select an experimental treatment and introduce it.
step 5. Choose a type of experimental design.
step 6. Conduct the experiment.
step 7. Organize and analyze the data.
step 8. Develop an experimental research report.
10. The following list presents criteria useful in this evaluation. For a good experiment, you would answer yes to each question:
ReplyDelete1. Does the experiment have a powerful intervention?
2. Does it employ few treatment groups?
3. Will participants gain from the intervention?
4. Did the researcher derive the number of participants per group some systematic way?
5. Were an adequate number of participants used in the study?
6. Were valid, reliable, and sensitive measures or observations used?
7. Did the study control for extraneous factors?
8. Did the researcher control for threats to internal validity?
Helen,
ReplyDeleteThat quote completely passed me by when I was reading the chapter, but that is really interesting! It's also a really cool fact! :)
QUESTION: Aside from not having enough funds when would using Within-Group or Individual Group Design be best?
ReplyDeleteQUOTE: “An experimental design is the traditional approach to conducting quantitative research.” (Page 298)
FACT: “Literature is used to justify the problem and intervention, and also to explain the results.” (Page 329)
1.) Define the purpose of an experiment and when you would use this design.
ReplyDeleteA) the purpose of an Experiment is to “test an idea (or practice or procedure) to determine whether it influences an outcome or dependent variable.” “You use an experiment when you want to establish possible cause and effect between your independent and dependent variables.” (Page 299)
2.) Why do researchers use random assignments in experiments?
ReplyDeleteA) Researchers use random assignments in experiments to equally distribute any bias among all groups in the study. (Page 300)
3.) Describe the types of procedures used to control extraneous factors in an experiment.
ReplyDeleteA)
Pretests and Posttests- Measure on some attribute or characteristic that you assess before the treatment and then measure that attribute again after the treatment has been given.
Question 3 Cont....
ReplyDeleteCovariates- “Variables that the researcher controls for using statistics and that relate to the dependent variable but that do not relate to the independent variable.” (Page 302)
Matching of Participants- “The process of identifying one or more personal characteristics that influence the outcome and assigning individuals with that characteristic equally to the experimental and control group. Typically, experimental researchers match one or two of the following characteristics: gender, pretest scores, or individual abilities.” (Page 302)
Question 3 Still Cont...
ReplyDeleteHomogeneous Samples- “Selecting people who vary little in their personal characteristics.” (Page 303)
Blocking Variables- “A variable the researcher controls before the experiment stats by dividing (or ‘blocking’) the participants into subgroups (or categories) and analyzing the impact of each subgroup on the out come.” (Page 304)
4.) Describe how researchers manipulate the treatment condition.
ReplyDeleteA) To manipulate the treatment conditions the researcher will identify the treatment variables, Identify the conditions of the variables, and then manipulate the treatment conditions.” (Page 305)
5.) Define "outcome variable."
ReplyDeleteA) Outcome variables are “the dependent variables in an experiment that are the presumed effect of the treatment variables. They are also the effects predicted in the hypotheses in the cause-and-effect equation.” (Page 306)
6.) Explain how researchers compare groups in an experiment.
ReplyDeleteA) Researchers compare groups in an experiment by “obtaining scores for individuals or groups on the dependent variable and comparing the means and variance both within the group and between the groups.” (page 306)
7.) What are some internal and external threats to validity in an experiment?
ReplyDeleteA) Internal threats to validity are “problems that threaten our ability to draw correct cause-and-effect inferences that arise because of the experimental procedures or the experiences of participants. Of all the threats to validity, these are the most severe because they can compromise an otherwise good experiment.” (Page 308)
External Threats to validity in an experiment are “problems that threaten our ability to draw correct inferences from the sample data to other persons, settings, and past and future situations.” (page 310)
8.) Describe between-group and within-group experiments.
ReplyDeleteA) Between-Group Experiments are experiments that researchers compare two or more groups. There are different designs: True Experiments, Quasi- Experiments, and Factorial Designs. (Page 313-317)
Within-Group Experiments or Individual Designs are where “researchers study a single group. Types for designs assume several forms: time series, repeated measures, and single-subject designs.” (Page 318)
9.) List the steps in conducting an experimental study.
ReplyDeleteA)
1.Decide if an experiment addresses your research problem
2. Form hypotheses to test cause-and-effect relationships
3. Select an experimental unit and identify study participants
4. Select an experimental treatment and introduce it
5. Choose a type of experimental design
6. Conduct the experiment
7. Organize and analyze the data
8. Develop an experimental research report (Page 325-328)
10.) List the criteria for evaluating an experimental study.
ReplyDeleteA)
*Does the experiment have a powerful intervention?
*Does it employ few treatment groups?
*Will participants gain from the intervention?
*Did the researcher derive the number of participants per group some systematic way?
*Were an adequate number of participants used in the study?
*Were valid, reliable, and sensitive measures or observations used?
*Did the study control for extraneous factors?
*Did the researcher control for threats to internal validity? (Page 328)
Becky,
ReplyDeleteI liked your fact for this chapter and the question and quote were interesting, too. An extensive literature review can be a jouney in itself.
1.) Define the purpose of an experiment and when you would use this design.
ReplyDeleteA:
The purpose of experiment is to test the idea. Researchers use experiment design when they want to predict the possible effect of an independnt variable to a dependent variable.
2.) Why do researchers use random assignments in experiments?
A:
In my opinion, researchers use random assignment because the research has a huge number of participants and wants to generate only some amount of the whole population. Moreover, participants have more similarity and the differences will affect the result of the research.
3.) Describe the types of procedures used to control extraneous factors in an experiment.
A:
1. Pretest and Posttest.
2. Covariates.
3. Matching of participants.
4. Homogeneous sample.
5. Blocking variable.
4.) Describe how researchers manipulate the treatment condition.
ReplyDeleteA:
The researcher will assign the participants in the the different groups of experiment to see the effect of the ideas to the participants.
5.) Define "outcome variable."
A: creswell (2008, p. 306) stated that outcome variable is th dependent variale that is the presumed effect ofthetreatment varible.
6.) Explain how researchers compare groups in an experiment.
A:
The researche will compare the score of the diferent treatments on the results. Additionally, the researcher will compare means and variance of indivdual within a group and between different groups.
7.) What are some internal and external threats to validity in an experiment?
ReplyDeleteA:
Internal threats to validity in an experiment are problems that the experimental procedures or the experiences of participants.
External threats to validity in an experiment are problems that thresten our ability to draw correct inferences from the sample data to other persons, settings, and past and future situations.
8.) Describe between-group and within-group experiments.
A:
Between group experiments are the experiemnts that researcher compares the results of two or more groups. Each group has a diferent treatment. Researcher wants to see what level of each treatment is when compare with the others.
Within group expeiments are the experiements that researcher studies only one group of participants. Then theresearcher will compare the results of the participants in the group.
9.) List the steps in conducting an experimental study.
A:
1. Decide if an experiment addresses your research problem
2. Form hypotheses to test cause and effect relationships
3. Select and experimental unit and identify study parrticipants.
4. Select an experimental treatment and introduce it.
5. Choose a type of experimental design.
6. Conduct the experiment.
7. Organize andanalyze the data.
8. Develop an experimental research report.
10.) List the criteria for evaluating an experimental study.
A:
The researcher assesses the groups, intervention, measures, or observations, and extraneous factors, and control over threats to validity.
1. An experiment tests an idea to determine whether it influences an outcome or dependent variable. You use an experiment to determine cause and effect between two variables. You are trying to decide if the independent variable has an effect the dependent variable.
ReplyDelete2. Using random assignment make the experiment a more true rigorous experiment. Using random assignment also helps to weed out bias and helps to equally distribute participants.
3. Randomly assigning participants is one way to control extraneous factors. Pretest, covariates, matching of participants, homogeneous samples and blocking variables are all ways to control extraneous variables as well.
4. A researcher will physically intervene to alter the condition of the experiment. So you would intervene in one group and then leave not in another group.
5. The outcome variable is the dependent variable that is the presumed effect of the treatment variable. This is also the effect predicted in the hypothesis.
6. Group comparison is when you take all the scores and compare there means between groups and within groups. You also compare variance.
7. Internal threats to validity are history, maturation, regression, selection, mortality, interaction with selection, rivalry, testing, and instrumentation. Threats to external validity are interaction of selection and treatment, interaction of setting and treatment, and interaction of history and treatment.
8. Between group experiments is when a researcher compares tow or more groups. Within group experiment is comparing scores and results between individuals. Sometimes there aren’t enough individuals to have more than one group.
9. Decide if an experiment addresses your research problem, form a hypothesis, select an experimental unit and participants, select an experimental treatment, choose a design, conduct experiment, organize and analyze data, and develop and experimental report.
10. does the experiment have a powerful intervention, does it employ few treatment groups, will participants gain from intervention, did the reasercher derive the number of participants per group some systematic way, were an adequate number of participants use in the study, were valid, reliable, and sensitive emasures or observation used, did the study control for extraneous factors, and did the research control for threats to internal validity.
Fact:
Experimental research began in the late 19th century and early 20th centuries.
Question:
Can we use experimental design in our own studies for our project? This is the method that has made the most sense to me.
Quote:
You should use random assignment whenever possible. This removes many potential threats to validity.
Helen,
ReplyDeleteGood question! You have to really look at your research questions and think about what you are studying. If you do this, you avoid making it too complicated in the end. I would say that some people make their studies too complicated with too many parts, and it is hard to prove what they are trying to say in the end. Have a good research question or a couple of questions to examine. You cannot look at one hundred questions for one study.
Keep up the good work!
Rebecca,
ReplyDeleteYou have to look at what your research questions are and what you have available to use to try and answer these. That will affect your choice here.
Keep up the good work!
Jessica,
ReplyDeleteIf you think that is the best design to fit your research questions, talk to your chair about it and see what he or she says about it. They will be your guide through your capstone project.
Keep up the good work!
Prueska,
ReplyDeleteGOOD JOB! Keep up the good work!
Thank you Dr. Hendrix.
ReplyDeleteAfter Halloween, I have time to do my homework.
The quote that I think it is useful for writing hypotheses is ,"Hypotheses are often based on relationsps found in studies by past researchers or contained within theories that are beng tested and cotinually revised (Creswell, 2008, p. 325)."
My question for ths chapte is, "Can we collect databy using qualitative method, but use statistic in quantitative research to interprete data? and Will can be validable for the research?"
The fact that I learn in this chapter is ,"quantitative research has a pretty long history since 1940."
1. The purpose is to test an idea to determine whether it influences an outcome or dependent variable. You would use an experiment when you want to establish cause and effect between your independent and dependent variables.
ReplyDelete2. So that any bias in the personal characteristics of individuals in the experiment is distributed equally among the groups.
3. A pretest provides a measure on some attribute that you assess for participants in an experiment before they receive treatment. A posttest provides a measure on an attribute that is assessed for participants after a treatment. Covariates are variables that the researcher controls for using statistics that relate to the dependent variable but don't relate to the independent variable. Matching is a process of identifying one or more personal characteristic that influence the outcome and assigning individuals with that characteristic equally to the experimental and control groups. Homogenous samples is selecting people who very little in their personal characteristics.
4. The researcher physically intervenes to alter the conditions experienced by the experimental unit.
5. The dependent variable that is the presumed effect of the treatment variable.
6. They obtain scores for individuals or groups on the dependent variable and compare the means and variance both within the group and between groups.
7. Internal threats might be: history, maturation, regression, mortality, compensatory rivalry. External threats might be interaction of selection of treatment, interaction of setting and treatment, or interaction of history and treatment.
8. Between-group experiments include true experiments, where researchers randomly assign participants to different experimental treatments, quasi-experiments, where assignments are not random, and factorial designs, where researchers study two or more independent variables. Within-group experiments include time-series experiments, where researchers study a group, over time, using pretest and posttest measures, repeated measures design, where researchers compare a group's performance under one experimental treatment with its performance under another experimental treatment.
9.
1. Decide if the experiment addresses your research problem. 2. Form a hypothesis 3. Select an experimental unit and identify study participants. 4. Select an experimental treatment and introduce it. 5. Choose a type of experimental design. 6. Conduct the experiment. 7. Organize and analyze the data. 8. Develop an experimental research report.
10.
Does the experiment have a powerful intervention?
Does it employ few treatment groups?
Will participants gain from the intervention?
Did the researcher derive the number of partisans in per group in systematic way?
Were an adequate number of participants used?
Were valid, reliable, and sensitive measures used?
Did the study control the extraneous factors?
Did the researcher control for threat internal validity?
1. The purpose is to test an idea to determine whether it influences an outcome or dependent variable. You would use an experiment when you want to establish cause and effect between your independent and dependent variables.
ReplyDelete2. So that any bias in the personal characteristics of individuals in the experiment is distributed equally among the groups.
3. A pretest provides a measure on some attribute that you assess for participants in an experiment before they receive treatment. A posttest provides a measure on an attribute that is assessed for participants after a treatment. Covariates are variables that the researcher controls for using statistics that relate to the dependent variable but don't relate to the independent variable. Matching is a process of identifying one or more personal characteristic that influence the outcome and assigning individuals with that characteristic equally to the experimental and control groups. Homogenous samples is selecting people who very little in their personal characteristics.
4. The researcher physically intervenes to alter the conditions experienced by the experimental unit.
5. The dependent variable that is the presumed effect of the treatment variable.
6. They obtain scores for individuals or groups on the dependent variable and compare the means and variance both within the group and between groups.
7. Internal threats might be: history, maturation, regression, mortality, compensatory rivalry. External threats might be interaction of selection of treatment, interaction of setting and treatment, or interaction of history and treatment.
8. Between-group experiments include true experiments, where researchers randomly assign participants to different experimental treatments, quasi-experiments, where assignments are not random, and factorial designs, where researchers study two or more independent variables. Within-group experiments include time-series experiments, where researchers study a group, over time, using pretest and posttest measures, repeated measures design, where researchers compare a group's performance under one experimental treatment with its performance under another experimental treatment.
9.
1. Decide if the experiment addresses your research problem. 2. Form a hypothesis 3. Select an experimental unit and identify study participants. 4. Select an experimental treatment and introduce it. 5. Choose a type of experimental design. 6. Conduct the experiment. 7. Organize and analyze the data. 8. Develop an experimental research report.
10.
Does the experiment have a powerful intervention?
Does it employ few treatment groups?
Will participants gain from the intervention?
Did the researcher derive the number of partisans in per group in systematic way?
Were an adequate number of participants used?
Were valid, reliable, and sensitive measures used?
Did the study control the extraneous factors?
Did the researcher control for threat internal validity?
1.) Define the purpose of an experiment and when you would use this design.
ReplyDeleteAn experiment is when you test an idea to see if it influences the dependent variable or outcome. You use an experimental design when you want to determine if the independent variable influences the dependent variable to establish a cause and effect relationship.
2.) Why do researchers use random assignments in experiments?
Random assignments is when the researcher assigns all participants to random groups in the experiment. Random assignments are done so that any bias in the characteristics of the individuals are distributed randomly. This provides a control for extraneous characteristics of the participants in the study.
3.) Describe the types of procedures used to control extraneous factors in an experiment.
Random assignments is a type of procedure used before the experiment involving placing participants in random groups. A pretest is used to measure a characteristic or attribute of a participant before the experiment begins in order to compare with the post-test after the experiment. Another method is using analysis of covariance procedure. Covariates are variables the researcher finds, besides the independent variable, that may influence the dependent variable. The analysis of variance statistical procedure adjust the dependent variable score to take into account covariates. The next method is matching, which matches participants by a specific characteristic and places them equally into the control and experimental groups. The procedure, homogenous samples, selects people who vary little in their characteristics. The last procedure is blocking variables. In this procedure the researcher divides the participants into homogeneous sub groups and then randomly places each of them in the experimental or control group.
4.) Describe how researchers manipulate the treatment condition.
ReplyDeleteIn an experimental design the researcher physically alters the conditions experienced by the experimental unit. For example, the reward or instruction for an experiment given to the participants.
5.) Define "outcome variable."
The outcome variable is the dependent variable that is presumed to be an effect of the independent variable and also the effect predicted in the hypothesis.
6.) Explain how researchers compare groups in an experiment.
The researcher first gathers scores for individuals or groups of the dependent variable. Then compare the means and variance both within the group and between groups.
7.) What are some internal and external threats to validity in an experiment?
ReplyDeleteA threat to validity is when the a design issue causes a false reading about cause and effect between treatment and the outcome of the experiment based on data. Threats to internal validity are problems that interfere with the researcher’s ability to draw cause and effect inferences, because of problems with procedures or experiences of the participants. There are three categories of threats to internal validity. This first is addresses threats related to participants and includes, history, maturation, regression, selection, mortality, and interactions with selection. The second category addresses threats related to treatment and includes, diffusion of treatment, compensatory equalization, compensatory rivalry, and resentful demoralization. The last threat to internal validity is threats that relate to the procedures and include testing and instrumentation.
Threats to external validity are problems that arise during an experiment that threaten the ability of the researcher to draw correct inferences about the sample data to generalize the conclusion to other persons, settings, and past and future situations. The three main threats to external validity are the interaction and selection of treatment, interaction of setting of treatment, and interaction of history and treatment.
8.) Describe between-group and within-group experiments.
The between group designs are when experimenters compare two or more groups. The first between group design is true experiment where groups are picked through random assignment. Quasi experiments are used when the experimenter cannot pick the groups. The third between group design is factorial design where the experimenter studies two or more categorical, independent variables for two or more levels.
With-In group designs are used when the researcher cannot use more than one group. One type of with-in group design is time series where an experimenter studies one group for a period of time. In a repeated measures design a single group participate in all experimental designs with each group becoming it’s own control. A single subject design is when a researcher wants to study the behavior of an individual rather than a group.
9.) List the steps in conducting an experimental study.
ReplyDelete1. Decide if and experiment addresses your research problems.
2. Form hypothesis to test cause and effect relationships.
3. Select an experimental unit and identify study participants.
4. Select an experimental treatment and Introduce it.
5. Choose a type of experimental design.
6. Conduct the experiment.
7.Organize and analyze the data.
8. Develop an experimental research report
10.) List the criteria for evaluating an experimental study.
A good experimental study includes:
-A powerful intervention
-Few treatment groups
-Participants gain from the experience
-The researcher derives the number of participants in a group in a systematic way
-An adequate number of participants
Valid, reliable, sensitive measures or observation
-Control of extraneous factors
-Control for threats to internal validity