Midterm Exam Flashcards
(30 cards)
Theory
a model to explain what we observe. All theories are wrong
Hypothesis
a clear, concise, testable statement. Similar to educated guess.
Descriptive Research
information about the frequency or amount of something (mean, median, mode) (ex: statistics on new Vanderbilt class)
Correlational Research
descriptions of the differences between groups; compare two groups on one variable (ex: difference in preference between men and women between chocolate preferences)
Comparative Research
description of the relationship between variables (ex: the relationship between height and weight)
Experimental Research
an investigation characterized by the direct manipulation of one variable (the cause) so its effect can be seen on another variable (the effect) while controlling for other extraneous variables
Be able to write an APA 6th edition citation for a peer-reviewed journal publication.
Author, A.A., & Author, B.B. (year). Title of article. Title of Journal, volume #, nn-nn.
Internal validity
the extent to which the independent variable, and not other extraneous variables, produce the observed change in the dependent variable (ex: checking weight on scale)
External validity
the extent to which the results of a study can be generalized to other subjects, setting and time
z-score
the relationship of one score to the norm group in terms of standard units; how many standard deviations above or below mean is a score; z=(raw score-mean)/SD
Effect size
a measure of the magnitude and difference of the means of two groups. ES=[Mean(control) - mean (experimental)]/SD(control). Effect size helps readers understand the significance of the results whereas p-values only tell if an effect exists.
Correlation Coefficient
Correlation - a measure of the strength of the relationship between two variables. Strength 0 to 1, 0 indicates no relationship (no predictive power), 1 indicates a perfect relationship (perfect predictive power); direction: positive or negative. Straight line = 1.00, Corn on the Cob = 0.75, Football = 0.5, Circular = 0.0 An outlier will move the correlation coefficient closer to zero.
Words of estimative probability
words that convey your degree of confidence or certitude in very clear terms. (Impossible, Unlikely, 50/50, Likely, Certain). Important for analysts or people making decisions to tell someone and convey to them clearly your understanding of the fact
Weasel Words
words that don’t convey at all with any degree of certitude or confidence what the likelihood of something is.
What are the ways of knowing we discussed in class? Why are some ways better than others?
- Personal Experience - most people weight the most, but only 1 data point out of thousands and could be outlier; people can have very different perceptions (eyewitness testimony is notoriously poor, so can’t be very accurate)
- Reason and Intuition - logic and formal reasoning, but doesn’t make it true
- Authority - just because someone has Ph.D. doesn’t mean its true or not believing because of who someone is
- Tradition - finding answers through long-established customs, but based on idealized past so possibly not best way moving forward
- Systematic Inquiry - systematic process for collecting and processing information. Systematic, testable and objective and allows us to examine process as well as results. Not all research is equally good so helps discern good research.
What’s the risk of believing something simply because it’s obvious?
Might be fooled. People have a tendency to believe any reasonable statement about human behavior. Baratz’s study shows this. If someone provides a reasonable statement with some explanation that sounds logical, people will buy into it. Then if have data with correlation coefficient, then they will really believe it.
What’s the difference between correlation and causality? What’s the benefit of correlational data? What’s required to make causal claims? What is the risk of confusing these two?
Correlation is the relationship between two variable. Benefit is you can use one variable to predict another. Causality is best established through experimental research design. Correlation doesn’t give evidence for cause and effect relationship. People get tricked because they can think of causes for relationship. One doesn’t tell us anything about the other. Could be a cause and effect relationship, but if low correlation then can’t be the cause.
List the required elements of qualitative and quantitative research questions and give examples
- Quantitative Research: Identifies specifically: 1) the variables, 2) the relationship between them, and 3) the subjects. Can be descriptive, correlational/comparative, or experimental (causal). (what is the relationship between…)
- Qualitative Research: identifies specifically: 1) the central phenomenon, 2) the participants, and 3) the site. (perceptions of…)
How are sampling error, sampling fluctuation, and statistical significance related? How can you reduce sampling error and increase the likelihood your results will be statistically significant?
Sampling Error: the value for the sample is not equal to the true population value. Reduce by increasing size of sample
Sampling Fluctuation: when take two samples from same population. When difference in samples, larger than expect from sampling fluctuation, say it’s a statistically significant difference
Statistical Significance: a mathematical test that gives a yes/no answer to the question” “Are the differences we see larger than we would expect than from sampling fluctuation alone?”. Increase likelihood of results being statistically significant by increasing number of people in your study
How are theories and hypotheses related?
hypotheses are generated from theories and to the extent that we provide evidence from the hypothesis that’s true is true our theories support it
What are statistical significance, effect size, and practical significance? What does each tell us?
Statistical Significance: a mathematical test that gives a yes/no answer to the question: are the differences in outcomes we observe larger than from sampling fluctuation alone?
Effect Size: tells us the magnitude and direction of the difference between two groups/samples of data. Tells us if one is higher than the other and by how many standard deviationsPractical Significance: answers the question: so what? What does it mean?
Ex: Vanderbilt football
What are the goals and strategies (3 each) for sampling in qualitative and quantitative research?
Qualitative: get the most informed participants
1. use network/snowball sampling
2. typical case (representative participant)
3. extreme case (unique/atypical participant)
Quantitative: to get a representative sample of the population you want to generalize the results to
1. simple random sampling
2. stratified sampling (proportion of subjects in each strata in the population are reflected in the proportions of subjects in each sample strata)
3. cluster sampling (district, school)
What’s so good about pretest-posttest control group experiments? Be able to draw a diagram with the key elements and label the purpose(s) of each in the context of a real-world study.
Pretest-Posttest Control Group Experiments
- Control Group: To help reduce threats to internal validity. This is not required of experiments but is very important.
- Randomly Assigned Subject: to help ensure equivalence between the two groups…on the dependent measures as well as all others
- Pretest: to test for equivalence of the groups at the start and for baseline data to calculate pretest/posttest delta
- Subject Treatments: the experimental group gets the treatments, and the control group gets something unrelated to the DV
- Posttest: measure the delta between pretest and posttest and measure the delta between groups on the posttest
- Delayed Retention Test: to determine whether the effects are lasting or whether they fade quickly
- Experiment Specific information: subjects, dependent variable, treatments
What are the 7 Survival Skills?
- Critical Thinking and Problem Solving
- Collaboration Across Networks and Leading by Influence
- Agility and Adaptability
- Initiative and Entrepreneurialism
- Effective Oral and Written Communication
- Accessing and Analyzing Information
- Curiosity and Imagination