Documents about Confounding Variables

  • 2 Pages

    17

    USC, COMM 202

    Excerpt: ... Experimental Designs Reviews & More 9/17/08 Note: for test, know how to id the different research methods. Experimental Methods -When are experiements appropriate? - When your focus is a how an iv affect an dv. - Trying to explain causal explanation Basic Setup of an Experiment - We try to manipulate iv to determine affect on dv. Confounding Variable - What are they? - A variable that can explain what is seen. - What do you want to do with them in the context of an experiment? - Which types of validity of an experiment/study do confounding variables threaten? - It could affect the way the experiment happens/the design. - INTERNAL validity? Ruling out Alternative Explanations - Internal Validity- Have I ruled out or controlled for other reasons that could be giving me these results? - External Validity- How research from one internally valid study might be generalizable to another context. Tension between external and internal validity. - As you increase external validity, you open threats to internal validity ...

  • 1 Pages

    hw6and7

    Penn State, STAT 200

    Excerpt: ... ink is represented by this sample? In an observational study, there is a risk of confounding variables . Does the story mention whether the researchers controlled for any confounding factors? If so, what were the confounding variables ? If not, what confounding variables should they have controlled for? Note at the bottom of the web site page, there are links to stories from previous days. HOMEWORK 7 Turn in answers to the Lab 11 activities. If you need a fresh copy of Lab 11, you can find one at the course web site. The direct link to the file is: www.stat.psu.edu/~rho/stat200/lab11.pdf ...

  • 38 Pages

    290a_June11

    Arizona, PSYC 290 A

    Excerpt: ... ffee & nice barrista -> no crankiness Can we tease apart coffee type (caf or decaf) and friendliness of barrista (rude or nice)? Regular coffee & rude barrista -> crankiness Regular coffee & nice barrista -> crankiness Decaf coffee & rude barrista -> no (or little) crankiness Decaf coffee & nice barrista -> no crankiness The effect of the friendliness of the barrista can be eliminated, thus it was a confounding variable MEDIATING vs. CONFOUNDING VARIABLE Mediating variables cannot be eliminated (can be varied - higher arousal) Confounding variables can be eliminated if identified and controlled for (regular coffee still made you cranky, regardless of the barrista's friendliness) DIRECTIONALITY PROBLEM Poor reading ability and erratic eye movements Schools concluded that deficient oculomotor skills caused reading problems Schools erroneously trained such readers to improve their eye movements Actually poor word recognition and comprehension causes erratic eye ...

  • 4 Pages

    Psyc 103 Lecture 2

    UCSD, PSYC 103

    Excerpt: ... ing variables Give 125 study guides to random students "If you use that study guide, you will 100% correct on the quiz next week?" power of suggestion, "experimental bias" "demand characteristics" o understands demands and tries to do it to make experimenter happy o purpose- identify cause and effect o advantages: precise control, ID cause and effect o disadvantages: ethical concerns, practical limitations, artificiality of lab conditions, confounding variables (any variable that the experimenter cant control and affect the results), biases (experimenter and participant) Biases Blind? Double-blind? o Ben ,n Willard (two blind rats) o Half of rats injected with memory drug, half with saline o Numbers tattooed on ears, odd numbered were getting drugs and even numbers were getting placebo o Were some difference in they way they measured Habituation Studies o Mom was tilting infant to look at the right information o Participant bias More (critical) experimental jargon: Informed consent Debriefing o Take ...

  • 4 Pages

    sm_chapter_11

    Penn State, STAT 100

    Excerpt: ... CHAPTER 11 SOLUTIONS AND MINI-PROJECT NOTES CHAPTER 11 RELATIONSHIPS CAN BE DECEIVING EXERCISE SOLUTIONS 11.1 Both firewood sales and cough drop sales are likely to increase during the cold season. No, it does not imply that fires cause coughs! No, you wouldn't necessarily conclude that walking causes lower weight. People who prefer to exercise (walk) may also be people who keep their weight under control, eat less fat, and so on. Reason 1 could be possible but isn't likely, that milk-drinking alone is responsible for low risk of stroke. Reason 2 is not likely, since it would say that a low risk of stroke causes people to drink milk, and vice versa. People don't usually even know whether or not they are at risk for strokes. Reason 3 could be possible, that milk-drinking is one of many factors that reduces the risk of a stroke. Reason 4 is quite likely, that confounding variables exist. One example is general good diet and good health, which leads to reduced stroke risk. Reason 5 is likely, that both reduced ...

  • 2 Pages

    PIA! # 1

    Rhode Island, PSYCHOLOGY 143

    Excerpt: ... _ 3. Based upon what you observed, identify two variables that will probably be shown to be correlated in this study. _ _ 4. Do you expect a positive or negative correlation? Why? _ EXPERIMENTAL? _ Based upon what you observed, what was an important independent variable in this study? Expecting Parents, pregnancy _ What was an important dependent variable? Martial Satisfaction after pregnancy or the presence of a newborn 5. What were the limitations of the research in which you participated and how would you improve upon the procedures used in this study? (For example, were there any potential confounding variables that remained uncontrolled? Explain your answer.) This experiment had some confounding variables , one being that the researcher was not aware to whether or not the parents planned to have a baby or it was a surprise that could affect moods and the satisfaction they feel on the marriage. T ...

  • 9 Pages

    CH 3 intro bb

    Tulane, PSYCH 101

    Excerpt: ... CH3: NATURE, NURTURE, AND HUMAN DIVERSITY Genes Chromosomes DNA How genes affect behavior Proteins Polygenic influence Genotype Phenotype Behavior Genetics Heritability Selective Breeding Human Studies Family studies, confounding variables Twin studies Identical and fraternal twins Confounding variables Adoption Studies Adopted twins Confounding variables Interpreting Behavior Genetics Findings Group Differences Heredity and Environment Interact Environmental influences on human behavior Gene-Environment Interactions Environment acts on genes Affects if genes are expressed Affects how genes are expressed Genes act on environment Passive genotype-environment correlations Evocative genotype-environment correlations Active genotype-environment correlations Evolutionary Psychology Natural Selection Adaptive Behaviors Depends on environment Gender Mating strategies Short-term vs long-term Evidence M ...

  • 2 Pages

    Study guide for week 1

    Lehigh, PSYC 121

    Excerpt: ... endent Variable (DV) Independent Variable (IV) 13 13 3 Class Notes (cont.) Random assignment Confounding variables Experimenter effects Correlation (positive and negative) Reverse causality problem 3rd variable effect Contact hypothesis Jigsaw classroom ...