Clever Hans
- Wilhelm von Austen
- Hans the horse did simple math and spelling questions by tapping his foot on the ground
- When Austen stood farther away or didn’t know answer, accuracy dropped
Why?
- Hans was very perceptive → picked up subtle body language from owner
- Austen gave Hans unconscious cueing
- Austen would unconsciously tense up or look more intensely when Hans got the
right answer
- Clever Hans Effect: person picks up signals from experimenter, even if they are not
doing it on purpose
- Shows importance of double blind studies
- If both participant and researcher don’t know what will happen or who is
affected → researcher can’t unconsciously cue the participant
- Consider proximity and whether or not experimenter answer when conducting research
- Empirical investigation: collecting objective information firsthand by making careful
measurements based on direct experience
- Theory: testable explanation for a set of facts or observations
- Solid idea based on experimentation and proof (empirical studies)
- General explanation, properties
- Hypothesis: statement predicting the outcome or describing the relationship between
variables in a study
- Variable: anything that can vary among participants in a study
- Operational definition: describes exactly what the variable are and how they are
measured within the context of your study
- Explain what they mean in real life
- Be specific → determines reliability of study
- Independent variable: stimulus condition that experimenter manipulates independently
- Whatever is being manipulated in the experiment and should bring about change
- Dependent variable: measured outcome r the response of subjects in the study
- Whatever is being measured in the experiment
- Is dependent on the independent variable
- Cause and effect / stimulus and response → must have operational definitions
- Replicate: repeat a study again to see if same results are obtained
- To control bias → done by someone that’s not the original researcher
- Confounding variables: variables that have unwanted influence on outcome of an
experiment → other possible explanations to the result
, - When designing experiment, must show how you neutralized confounding
variables so they don’t affect results
- Random selection: each subject of the sample has an equal likelihood of being chosen
for the experimental group (group affected by independent variable)
- Ie. drawing names out of hat
- Random sample: sample group of subjects selected by chance or without biased
selection techniques
- Make sure sample has a range of people that reflects accurately on population
- Experimental group: group being affected by independent variable
- Control group: group which variable is not being tested on → doesn’t receive any
treatment
- Acts as benchmark to compare results of experimental group
- Group matching: ensure experimental and control groups are equivalent on some
criterions (sex, race, height, etc.)
- Stratified sampling / representative sample: sample reflects the distribution of
important variables in the larger population
- Variables like age, socioeconomic status, ethnicity, education, etc.
- The percentage of these variables in larger pop. matches sample
Scientific method: 5 step process for empirical (solid) investigation of hypothesis, tested under
conditions designed to control biases and subjective judgments
1. Developing a hypothesis
- Consider the variables
- Must be testable and falsifiable
- If not falsifiable = scientific
- Need an operational definition
2. Performing a controlled test
- Tests must be rigorous before accepted as legitimate theory
- Should be able to replicate anywhere w/ similar results
- Account independent variable
3. Gathering objective data
- Getting information by direct observation
- Look dependent variable, not experimenter’s hopes
4. Analyzing the results: accepting or rejecting the hypothesis
- Look at the data collected and see if it supports or disproves hypothesis
- Analyzing: were there external factors?
5. Publishing, criticizing, and replicating results
- Make sure results withstand criticism and scrutiny of science community
- Replicate w/ a different researcher
, Methods of Research
Experimental method: researcher controls and manipulates the conditions, including
independent variable (strongest, most scientific method)
- Proves causal relationships → cause and effect
- Laboratory experiments → controlled
- Field experiments → things that happen in outside world
- Designing an experiment:
1. Hypothesis
2. Pick population (who is participating in experiment) – random selection, then
random assignment
3. Operationalize variables (define)
4. Identify independent and dependent variables
5. Look for extraneous variables (other unconsidered variables that might affect
experiment)
6. Type of experiment: blind, double blind, etc.
7. Gather data
8. Analyze results
- Be aware of and neutralize confounding variables
- Control: make sure all groups being tested have the same conditions
- Prevents situation-relevant confounding variables
Sampling:
- Make sure subjects are drawn from a population which consists of everyone who fits the
description of your test group
- Ie. when testing intelligence, make sure there is a range of intelligence present
- (FIRST) use random selection to ensure group represents the demographic we want
- (SECOND) use random sampling → participants chosen in unbiased manner
- (THIRD) randomly assign them into two groups → control for confounding variables
- Random assignment prevents participant-relevant confounding variables →
participants will choose group w/ an activity they prefer
- Two groups: experimental group and control group
- Group matching
- Make sure sample is a representative sample
Non-experimental designs: when we can’t do experiments due to ethical or practical reasons
- We must do other types of research
- Ex post facto: research where we choose subjects based on a pre-existing condition
- Like a case study on particular illnesses (ie. cancer)
- Wilhelm von Austen
- Hans the horse did simple math and spelling questions by tapping his foot on the ground
- When Austen stood farther away or didn’t know answer, accuracy dropped
Why?
- Hans was very perceptive → picked up subtle body language from owner
- Austen gave Hans unconscious cueing
- Austen would unconsciously tense up or look more intensely when Hans got the
right answer
- Clever Hans Effect: person picks up signals from experimenter, even if they are not
doing it on purpose
- Shows importance of double blind studies
- If both participant and researcher don’t know what will happen or who is
affected → researcher can’t unconsciously cue the participant
- Consider proximity and whether or not experimenter answer when conducting research
- Empirical investigation: collecting objective information firsthand by making careful
measurements based on direct experience
- Theory: testable explanation for a set of facts or observations
- Solid idea based on experimentation and proof (empirical studies)
- General explanation, properties
- Hypothesis: statement predicting the outcome or describing the relationship between
variables in a study
- Variable: anything that can vary among participants in a study
- Operational definition: describes exactly what the variable are and how they are
measured within the context of your study
- Explain what they mean in real life
- Be specific → determines reliability of study
- Independent variable: stimulus condition that experimenter manipulates independently
- Whatever is being manipulated in the experiment and should bring about change
- Dependent variable: measured outcome r the response of subjects in the study
- Whatever is being measured in the experiment
- Is dependent on the independent variable
- Cause and effect / stimulus and response → must have operational definitions
- Replicate: repeat a study again to see if same results are obtained
- To control bias → done by someone that’s not the original researcher
- Confounding variables: variables that have unwanted influence on outcome of an
experiment → other possible explanations to the result
, - When designing experiment, must show how you neutralized confounding
variables so they don’t affect results
- Random selection: each subject of the sample has an equal likelihood of being chosen
for the experimental group (group affected by independent variable)
- Ie. drawing names out of hat
- Random sample: sample group of subjects selected by chance or without biased
selection techniques
- Make sure sample has a range of people that reflects accurately on population
- Experimental group: group being affected by independent variable
- Control group: group which variable is not being tested on → doesn’t receive any
treatment
- Acts as benchmark to compare results of experimental group
- Group matching: ensure experimental and control groups are equivalent on some
criterions (sex, race, height, etc.)
- Stratified sampling / representative sample: sample reflects the distribution of
important variables in the larger population
- Variables like age, socioeconomic status, ethnicity, education, etc.
- The percentage of these variables in larger pop. matches sample
Scientific method: 5 step process for empirical (solid) investigation of hypothesis, tested under
conditions designed to control biases and subjective judgments
1. Developing a hypothesis
- Consider the variables
- Must be testable and falsifiable
- If not falsifiable = scientific
- Need an operational definition
2. Performing a controlled test
- Tests must be rigorous before accepted as legitimate theory
- Should be able to replicate anywhere w/ similar results
- Account independent variable
3. Gathering objective data
- Getting information by direct observation
- Look dependent variable, not experimenter’s hopes
4. Analyzing the results: accepting or rejecting the hypothesis
- Look at the data collected and see if it supports or disproves hypothesis
- Analyzing: were there external factors?
5. Publishing, criticizing, and replicating results
- Make sure results withstand criticism and scrutiny of science community
- Replicate w/ a different researcher
, Methods of Research
Experimental method: researcher controls and manipulates the conditions, including
independent variable (strongest, most scientific method)
- Proves causal relationships → cause and effect
- Laboratory experiments → controlled
- Field experiments → things that happen in outside world
- Designing an experiment:
1. Hypothesis
2. Pick population (who is participating in experiment) – random selection, then
random assignment
3. Operationalize variables (define)
4. Identify independent and dependent variables
5. Look for extraneous variables (other unconsidered variables that might affect
experiment)
6. Type of experiment: blind, double blind, etc.
7. Gather data
8. Analyze results
- Be aware of and neutralize confounding variables
- Control: make sure all groups being tested have the same conditions
- Prevents situation-relevant confounding variables
Sampling:
- Make sure subjects are drawn from a population which consists of everyone who fits the
description of your test group
- Ie. when testing intelligence, make sure there is a range of intelligence present
- (FIRST) use random selection to ensure group represents the demographic we want
- (SECOND) use random sampling → participants chosen in unbiased manner
- (THIRD) randomly assign them into two groups → control for confounding variables
- Random assignment prevents participant-relevant confounding variables →
participants will choose group w/ an activity they prefer
- Two groups: experimental group and control group
- Group matching
- Make sure sample is a representative sample
Non-experimental designs: when we can’t do experiments due to ethical or practical reasons
- We must do other types of research
- Ex post facto: research where we choose subjects based on a pre-existing condition
- Like a case study on particular illnesses (ie. cancer)
