Verified Document

Inferential Statistics What Are The Essay

Note that individual background variables such as sex and ethnicity do not satisfy the requirements of true experimental design since they cannot be purposively manipulated in this way (Practical assessment research and evaluation). True experiments are different from experimental design in that they are the only experiments that allow researchers to make causal conclusions based on study results and, therefore, provide greater internal validity (True experiments). It is only through random assignment that researchers can be assured that groups are truly comparable and that observed differences in outcomes are not the result of extraneous factors or pre-existing differences (Practical assessment research and evaluation). This means that the researcher needs so have control of the situation to have a reasonable chance of saying factors X and Y really affect outcome Z (True experiments). Internal validity is controlled in true experiments by assigning subjects to conditions randomly (i.e., only by chance can other variables be confounded with the independent variable) as well as controlling what, when, where, and how by controlling the way the experiment is conducted (True experiments - single-factor designs) through the use of control groups, random assignments to control and experimental groups and random assignments of groups to control and experimental conditions (True-experimental designs).

What are quasi-experimental designs? Why are they important? How are they different from experimental designs?

Practical assessment research and evaluation explains the quasi-experimental design. It consists of administering an outcome measure to two groups or to a program/treatment group and a comparison. For example, one group of students might receive reading instruction using one type of program while the other receives a different type of program. After twelve weeks, a reading comprehension test can determine which program was more effective.

Experimental research attempts to maintain control over all factors that may affect the result of an experiment so that a researcher can determine or predict what may occur. However, a quasi-experimental design does not meet all requirements necessary for controlling influences of extraneous variables (Practical assessment research and evaluation)....

In the student example above, the two groups might not be necessarily the same before any instruction takes place and may differ in important ways that influence what reading progress they are able to make. For instance, if it is found that the students in one of the groups perform better, there is no way of determining if they are better prepared or better readers even before the program and/or whether other factors are influential to their growth.
Still, quasi-experimental design is important because it is the best type of design often available for field studies when causal inference is desired (Quasi-experimental design). Explanations must be plausible given circumstances and consistent with data in situations where rival hypotheses has been shown to be implausible, but identification of what is and isn't plausible is not always apparent and interpretation issues must be carefully evaluated (Quasi-experimental design).

Bibliography

Comparative qualitative research methods. http://209.85.173.132/search?q=cache:3PulGqiG_ccJ:www.msu.edu/~lebas/Qual-Methods-2.ppt+single-case+and+small-N+research+designs&hl=en&ct=clnk&cd=6&gl=us

Cooper JO, Heron TE, Heward WL (2007). Applied Behavior Analysis (2nd ed. ed.). Prentice Hall.

ISBN 0-13-142113-1.

Descriptive and inferential statistics: Summary. http://www.habermas.org/stat2f98.htm

Kazdin. Wikipedia. http://en.wikipedia.org/wiki/Single_subject_design

Practical assessment research and evaluation http://pareonline.net/getvn.asp?v=5&n=14

Quasi-experimental design. http://209.85.173.132/search?q=cache:8PL0KDkAYPkJ:hcc.cc.gatech.edu/getDocument.php%3Fdoc%3D39+quasi-experimental+designs&hl=en&ct=clnk&cd=2&gl=us

Research methods. http://allpsych.com/researchmethods/trueexperimentaldesign.html

True experiments. http://www.wadsworth.com/psychology_d/templates/student_resources/workshops/res_methd/expermnts/expermnts_01.html

True-experimental designs. http://linguistics.byu.edu/faculty/henrichsenl/ResearchMethods/RM_2_08.html

True experiments - single-factor designs. http://axon.psyc.memphis.edu/~charlesblaha/3000/Lec%208%20True%20Exp/Lec%208%20True%20Exp%20-%20Part%201-STUDENTS.pdf

Sources used in this document:
Bibliography

Comparative qualitative research methods. http://209.85.173.132/search?q=cache:3PulGqiG_ccJ:www.msu.edu/~lebas/Qual-Methods-2.ppt+single-case+and+small-N+research+designs&hl=en&ct=clnk&cd=6&gl=us

Cooper JO, Heron TE, Heward WL (2007). Applied Behavior Analysis (2nd ed. ed.). Prentice Hall.

ISBN 0-13-142113-1.

Descriptive and inferential statistics: Summary. http://www.habermas.org/stat2f98.htm
Kazdin. Wikipedia. http://en.wikipedia.org/wiki/Single_subject_design
Practical assessment research and evaluation http://pareonline.net/getvn.asp?v=5&n=14
Quasi-experimental design. http://209.85.173.132/search?q=cache:8PL0KDkAYPkJ:hcc.cc.gatech.edu/getDocument.php%3Fdoc%3D39+quasi-experimental+designs&hl=en&ct=clnk&cd=2&gl=us
Research methods. http://allpsych.com/researchmethods/trueexperimentaldesign.html
True experiments. http://www.wadsworth.com/psychology_d/templates/student_resources/workshops/res_methd/expermnts/expermnts_01.html
True-experimental designs. http://linguistics.byu.edu/faculty/henrichsenl/ResearchMethods/RM_2_08.html
True experiments - single-factor designs. http://axon.psyc.memphis.edu/~charlesblaha/3000/Lec%208%20True%20Exp/Lec%208%20True%20Exp%20-%20Part%201-STUDENTS.pdf
Cite this Document:
Copy Bibliography Citation

Related Documents

Inferential Statistics
Words: 643 Length: 4 Document Type: Term Paper

Working with Inferential Statistics Discussion In seeking to determine whether children exposed to movies created prior to the year 1980 caused more injuries than children who were exposed to movies after the year 1980, we formulate our null and alternative hypothesis as below: H0:µ before 1980=µ after 1980 H1:µ before 1980 ? µ after 180 µ is the mean of injuries The level of significance ?=0.05 From the result derived from the SPSS software at 95% confidence

Inferential Statistics to Evaluate Sample Data. Inferential
Words: 1017 Length: 4 Document Type: Research Paper

inferential statistics to evaluate sample data. Inferential Statistics are used to determine whether one can make statements where the results reflect that would happen if we were to conduct the experiment again with multiple samples. With inferential statistics, you are trying to reach conclusions that extend beyond the immediate data alone via inference. For instance, inferential statistics infer from the sample data what the population might think. Another example, inferential

Inferential Statistic Tests Used in Study. What
Words: 1125 Length: 4 Document Type: Research Paper

inferential statistic tests used in study. What were these tests typically used for? Why were they chosen here? The objective of the study was to analyze the true costs of hypertensions. The researchers did this by analyzing the data of four patient groups using propensity score matching to control for possible bias in cost estimates. The regression model that followed estimated for costs of hypertension by controlling for sex, length

Analysis of Inferential Statistics and Discontents
Words: 1242 Length: 4 Document Type: Research Paper

Inferential Statistics and Their Discontents The notion of conducting statistical testing is increasingly important because of the significance testing is the basis of statistics. Inferential statistics is an important part of this process despite the necessity of descriptive statistics, which help in data exploration and interpretation. Actually, one of the most important aspects of inferential statistics is significance testing largely because this is what statistics are centered on. Generally, inferential statistics

Decision Modeling Inferential Statistics
Words: 2286 Length: 4 Document Type: Essay

Inferential Statistics: Decision Modeling Decision Modeling: Inferential Statistics Decision models are important components of inferential statistics. They are crucial in helping researchers choose the most appropriate statistical test to use for their study. This text presents the various steps involved in decision modeling, and uses two studies to demonstrate how such models can be used to guide the decision on what test to use. Decision Models in Inferential Statistics Decision models play a crucial

Psychological Research Descriptive and Inferential Statistics Descriptive...
Words: 1173 Length: 4 Document Type: Research Paper

Psychological Research Descriptive and Inferential Statistics Descriptive statistics is an style of analysis that is used when wanting to describe the entire population under study. But the population studied must be small enough to include every case, or each subject. ("Definition") On the other hand, inferential statistics also studies a population, but the purpose is to expand the results to include a much larger population in general. (Healey) In descriptive statistics, the

Sign Up for Unlimited Study Help

Our semester plans gives you unlimited, unrestricted access to our entire library of resources —writing tools, guides, example essays, tutorials, class notes, and more.

Get Started Now