Measurement and Method Flashcards
Define:
scientific method
general procedures psychologists use for gathering and interpreting data
Define theory as it relates to research methods.
organized, testable explanation of phenomena
Other researchers must be able toreplicatethe results of an experiment to validate its conclusions.
What is replication?
obtaining similar results to a previous study using the same methods
What is hindsight bias?
explaining why something happened after it has occurred
What is a controlled experiment?
researchers systematically manipulate a variable and observe the response in a laboratory
Define:
hypothesis
prediction of how two or more factors are related
How do researchers specifically define what variables mean?
Researchers use operational definitions to precisely describe variables in relation to their study. For example, “effectiveness of studying” can be operationally defined with a test score.
What is the difference between an independent variable and a dependent variable in an experiment?
The factor being manipulated is theindependentvariable. The factor being measured is thedependentvariable.
Identify the independent and dependent variables:
If we test the hypothesis thatstudents who Brainscape to study, rather than simple flash cards, will learnmore (as measured byhigher test scores), then what is the independent variable? What is the dependent variable?
independent: method of studying (Brainscape versus regular flashcards)
dependent: amount learned, as measured bytheirtest scores
Define population as it relates to research methods.
all the individuals to which the study applies
Define sample as it relates to research methods.
subgroup of a population that constitutes participants of a study
What type of sample should be used in research?
Larger sample sizes are ideal because they are the most representative of the population.
The amount of difference between the sample and population is called __________.
sampling error
Which individuals are in the experimental group?
subjects who receive the treatment or manipulation of the independent variable
Which individuals are in the control group?
subjects who do not receive any treatment or manipulation
Subjects who receive the treatment are part of the __________, while those who do not receive the treatment belong to the __________.
experimental group; control group
Define random selection as it relates to research methods.
every individual from a population has an equal chance of being chosen for the sample
What type of experimental design uses experimental and control groups?
A between-subjects design uses an experimental group and a control group to compare the effect of the independent variable.
Which process is used to try to ensure there are no preexisting differences between the control group and the experimental group?
Random assignmentis used to assignthe sample participants into groups (e.g., experimental drug or placebo).
Random assignment means neither the experimentor nor the participants decide in which group the participantswill be, and eachparticipant has an equal chance of being assigned to a givenstudy groups (e.g., treatment vs. placebo).
Define:
confounding variable
any difference between the experimental group and the control group, besides the effect of the independent variable
a.k.a. third variable
makes the phenomenon at hand even more difficult to study because of complex interaction effects
List four types of confounding variables.
- experimenter bias
- demand characteristics
- placebo effect
- lack of counterbalancing
Define experimenter bias as it relates to confounding variables.
Experimenter bias occurs when a researcher’s expectations or preferences about the results of the study influence the experiment.
Define demand characteristics as they relate to confounding variables.
clues the participants discover about the intention of the study that alter their responses
Define placebo effect as it relates to confounding variables.
responding to an inactive drug with a change in behavior because the subject believes it contains the active ingredient
What is the Hawthorne effect?
individuals who are being experimented on behaving differently than in their everyday life
What type of experimental design uses each participant as his/her own control?
A within-subjects design exposes each participant to the treatment and compares their pre-test and post-test results. This design can also compare the results of two different treatments administered.
What is a single-blind procedure?
research design in which the subjects are unaware if they are in the control or experimental group
What is a double-blind procedure?
research design in which neither the experimenter nor the subjects are aware who is in the control or experimental group
Single-blind procedures aim to eliminate the effects of __________, while double-blind procedures use a third party researcher to omit the effects of __________.
demand characteristics; experimenter bias
How are quasi-experiments different from controlled experiments?
Random assignment is not possible
Differences in behavior between:
What types of research are considered quasi-experiments?
males and females
various age groups
students in different classes
in quasi-experiments.
correlational research
establishes a relationship between two variables
does not determine cause and effect
used to make predictions and generate future research
List three methods of data collection
- naturalistic observation
- surveys
- tests
Which two conditions must be met for an experiment to be considered a true experiment?
- the researcher manipulates the independent variable
- all participants are randomly assigned to the experimental and control condition
So, for instance, a study that compares how men versuswomen do on a given task would not be a true experiment because it is not possible to assign people to group (gender). (This examplewould be a quasiexperiment.)
Define naturalistic observation as it relates to correlational research.
Naturalistic observation consists of field observation of naturally occuring behavior, such as the way students behave in the classroom. There is no manipulation of variables.
What are surveys and why are they not always accurate?
type of correlational research
questionnaires and interviews given to a large group of people about their thoughts or behavior
individuals aim to be politically correct and socially accepted, leading them to give false answers
Define tests as they relate to correlational research.
research method that measures individual traits at a specific time and place
__________ studies start by looking at an effect and then attempt to determine the cause.
Ex post facto
What is the difference between the reliability and validity of a test?
•Reliable – consistent
When administered properly, does a test give similar results when used on different occasions?
•Valid – useful, meaningful
Does it measure what it claims to measure?
In order to be valid, a measure must be reliable. However, a measure can be reliable without being valid. For instance, imagine a scale that always reads 212 pounds, no matter what the weight is of the person who stands on it. That scale would be a reliable measure, but not a valid measure.
What is a case study?
detailed examination of one person or a small group
beneficial for understanding rare and complex phenomena in clinical research
not always representative of the larger population
What are the strengths and weaknesses of this research method?
experiments
Strengths:
determine cause and effect relationship between variables
control over confounding variables
Weaknesses:
no real-world generalizability
expensive
time-consuming
What are the strengths and weaknesses of this research method?
correlational research
Strengths:
easy to administer surveys or tests
inexpensive
minimal time needed
substantial real-world generalizability
Weaknesses:
no control over confounding variables
skewed or biased results
establishes a relationship, not causation
1) __________ data includemeasurements, such as scores on the Wisconsin Card Sorting Task (behavioral example) or scores on theMagical Ideation Scale (self report example), that can be readily expressed using numbers.
2) __________data,suchasclinicalinterviews, can be very descriptive and rich, but are challenging and ambiguous to interpret.
1) Quantitative
2) Qualitative
What are the four scales of measurement?
- nominal
- ordinal
- interval
- ratio
Define:
nominal scale
Data that arecategorical: Numbers haveno meaningexcept for convenience as labels. Examples: Hair Color (possibly coded red = 1; grey = 2; black = 3; brown = 4; blond = 5...) Political Party (possibly coded Democrat = 1; Republican = 2; Independent/Other =3) Gender (Male = 1; Female = 2; Prefer not to reply = 3).
Define:
ordinal scale
numbers are used as ranks
Examples:
The runner who wins the race is scored as 1, the runner who comes in second is scored as 2, the third is scored as 3, and so on.
Define:
interval scale
numbers that have a meaningful difference between them
Example:
Temperature: The difference between 10°F and 20°F is the same as between 30°F and 40°F.
Define:
ratio scale
numbers that have a meaningful ratio between them on a scale with a real zero point
Example:
Weight and height: If you weight zero pounds, you have no weight. 100 pounds is twice as heavy as 50 pounds.
Define:
statistics
analysis of numerical data regarding representative samples
Would temperature of Celcius andFarenheitbe measured on an interval scale or a ratio scale?
interval
If the temperature is 0°F, there is not “no temperature.” There is not a meaningful ratio between values. 100°F is not twice as hot as 50°F.
What are descriptive statistics?
numbers that summarize a set of research data from a sample
Define:
frequency distribution
an orderly arrangement of scores indicating the frequency of each score
What is the difference between a histogram and a frequency polygon?
Ahistogramis a bar graph and afrequency polygonis a line graph or a bell curve.
Define and list the three types of:
central tendency
Measures of central tendency describe the most typical scores for a set of research data.
- mode
- median
- mean
Define in terms of central tendency:
mode
most frequently occurring score in the data set
Define in terms of central tendency:
median
the middle score when the data is ordered by size
mean
arithmetic average of the scores in the data set
If two scores appear most frequently, the distribution is __________, and if there are three or more appearing most frequently, it is __________.
bimodal; multimodal
Which measure of central tendency is the most representative? The least representative?
mean is usually most representative, unless there are extreme outliers that pull the mean in a particular direction
median is less sensitive to outliers, but is a weak statistic
mode is the least representative
normal distribution
a bell-shaped, symmetrical curve that represents data about many characteristics, including the distribution of many human characteristics
In a normal distribution, approximatelytwo-thirds of the population will be within plus or minus one standard deviation of the norm (mean). Approximately 95% of the population will be within plus or minus two standard deviations of the mean. Over 99% of the population will fall within plus or minus three standard deviations of the mean.
When most of the scores are compacted on one side of the bell curve, the distribution is said to be __________.
skewed
Positively skewed distributions include a lot of small values and negatively skewed distributions include a lot of large values.
Define and list the three types of:
measures of variability
Measures of variability describe the dispersion of scores for a set of research data.
- range
- variance
- standard deviation
Define in terms of variability:
range
difference between the largest score and the smallest score
What do variance and standard deviation measure?
average difference between each score and the mean of the data set
Taller, narrow curves have less variance than short, wider curves.
What is azscore (a.k.a. standard score)?
allows for comparison between different scales
subtract mean from each score and divide by standard deviation
mean has a z score of zero
Define:
percentile score
percentage of scores at or below a particular score between 1 and 99
Example:
If you are in the 70th percentile, 70% of the scores are the same as or below yours.
Define:
Pearson correlation coefficient
statistical linear measure of the relationship between two sets of data
varies from -1 to +1
helps to make predictions about variables
Name the correlation coefficient for each and describe the relationship:
- perfect positive correlation
- no relationship
- perfect negative correlation
- r = +1
direct relationship:as one variable increases or decreases, the other does the same - r = 0
no relationship - r = -1
inverse relationship:as one variable increases or decreases, the other does the opposite
What type of graph plots single points to show the strength and direction of correlations?
scatterplot
What is the term for the line on a scatterplot that follows the trend of the points?
line of best fit or regression line
What is the difference between a null and an alternative hypothesis?
Nullhypotheses state that a treatment had no effect, whilealternativehypotheses state the treatment did have an effect in the experiment.
What is the difference between a Type I and Type II error?
Type Ierrors, or false positives, occur if the researcher rejects a true null hypothesis.Type IIerrors, or false negatives, occur if the researcher fails to reject a false null hypothesis.
What is apvalue?
Thepvalue lets you know if the finding is statistically significant, i.e., the likelihood ofthe findings being the result of chance. The lower thepscore, the less likely it is that the findings aredue to chance.
In order for a finding to be considered statistically significant, thepscore must be less than or equal to .05; in other words, a %5 or less likelihood that the finding is due to chance.
When is a finding statistically significant?
In psychology, a finding is considered statistically significant ifthe probability (alpha) that the finding is due to chance is less than 1 in 20 (p is less than or equal to0.05)
What method statistically combines the results of several research studies to reach a conclusion?
meta-analysis
Why did the American Psychological Association (APA) implement ethical guidelines?
Guidelines were set in place in the late 20th century to stress responsibility and morality in research and clinical practice
Dangerous and inhumane experiments such as Harlow’s rhesus monkeys, Zimbardo’s prison role-playing, and Milgram’s shock test led to the implementation of rules
What are the purposes of an Institutional Review Board (IRB)?
approve research being conducted at their particular institution
require participants give informed consent after hearing the risks and procedures
require debriefing of participants afterward with results of research
require humane and ethical treatment of animal and human subjects
__________ psychology is practical and designed for real world application, while __________ psychology is focused on research of fundamental principles and theories.
Applied; basic
Who founded the first psychology research lab?
Wilhelm Wundt
_______ was one of the first psychologists to demonstrate that one could study psychological processes using experimental psychology.
Hermann Ebbinghaus
Describe the work of Oswald Kulpe.
Kulpe was one of the earliest experimental psychologists who performed numerous experiments to prove his “imageless thought” to try and combat Titchener’s work and prove that there were some thoughts that did not have images to be analyzed.
Who was the first psychologist to introduce mental testing to the United States?
James McKeen Cattell
Who created the first intelligence test and what was its initial purpose?
The first intelligence test was created by Simon and Binet in 1905 for the purposes of ranking the intelligence of French children to select for mentally retarded children.
______ was a term developed by William Stern, which describes the ratio between someone’s chronological and his/her mental age.
Intelligence quotient (IQ)
Who authored the Stanford-Binet Intelligence test?
Lewis Terman
If I were to test a population of people taking care to sample a proportionate amount to the actual composition of the group, which kind of sampling would I be using?
stratified random sampling
If I know something may be a confounding factor, and I create pairs of participants based on similar levels of this factor to eliminate its effect, this is called_____?
matched-subjects design
Define:
counterbalancing
This is an experimental technique in which we make sure both the experimental and control group will experience both levels of the independent variable, just at different times.
Mary designed an experiment in which the groups were not randomly assigned and so the control and experimental groups were not the same, what kind of group design is this?
nonequivalent group design
If the results of my experiment are applicable to the entire population, my experiment is said to have __________ .
external validity
If I make inferences from a data set that go beyond the actual data points, this would be _________.
inferential statistics
An _______ is an extremely large or extremely small number that affects the measure of central tendency such that it is no longer accurately representative of the sample.
outlier
What are the properties of a normal distribution?
A normal distribution is represented by a normal curve. The scores will exist such that 68% of the scores are within 1 standard deviation of the mean and 96% of the scores will fall within 2 standard deviations of the mean.
Define:
T-score
Similar to a Z-score, a T-score sets up a curve such that the mean is always 50 and each standard deviation is 10. You simply convert each number to the T-score value for easy comparison and analysis.
What is the difference between a positive correlation and a negative correlation?
A positive correlation is one in which if one value increases, the other value will increase. A negative correlation is one in which if one value decreases, the other value increases.
What does a scatterplot look like?
…
The ________is the line one draws on the scatterplot to best represent the relationship between the two values.
line of best fit
Define:
factor analysis
Factor analysis uses multiple sets of correlations to see which variable correlations cluster together to create a factor or group of variables which are presumed to be measuring the same value, based on their high rates of correlation.
Describe the difference between the null hypothesis and the research hypothesis.
The null hypothesis states that there is no relationship between the two values tested. The research hypothesis states that there is a statistically significant relationship between the two values in our experiment.
The _____ is the level of certainty we wish to have that there is an actual relationship between the two values in an experiment.
alpha level
This is usually set at a 1 in 20 chance or an alpha level of 0.05.
