Why must the active manipulation of an independent variable involve 'active intervention of the researcher'?
Explanation
Active intervention by the researcher is the cornerstone of experimental control. By creating the groups and applying the conditions, the researcher breaks any natural links between participant characteristics and the independent variable, which is crucial for making valid causal inferences.
Other questions
What are the two fundamental features of an experiment, as described in the text?
In the Darley and Latané experiment on the bystander effect, what was the single independent variable?
What is the primary purpose of actively manipulating an independent variable in an experiment?
A researcher conducts an experiment with one independent variable that is manipulated to produce three distinct conditions. What is this type of design called?
What is the term for variables other than the independent and dependent variables that the researcher tries to control or minimize?
How do extraneous variables, when uncontrolled, make it difficult to detect the effect of the independent variable?
What is a confounding variable?
In the hypothetical study on the effect of mood on memory, why would IQ be considered a confounding variable?
What is defined as any intervention meant to change people's behavior for the better in psychological research?
In an experiment on the effectiveness of a new therapy, what is the purpose of a control condition?
What is the primary problem with using a no-treatment control condition when evaluating a new treatment?
What is a placebo?
To effectively control for placebo effects, what is the function of a placebo control condition?
In a study on the effectiveness of two arthroscopic surgery procedures, what did the control participants in the Moseley et al. study receive?
What defines a wait-list control condition?
When is it most sensible to compare a new treatment with the best available alternative treatment rather than a placebo control?
How do researchers make a clear distinction between the terms 'manipulation' and 'control' in the context of an experiment?
A researcher studies the health of people who already keep a journal versus those who do not. Why is this NOT considered an experiment?
What is the primary reason researchers try to control extraneous variables, as illustrated by the hypothetical data in Table 5.1?
According to the text, limiting participants in a language study to only right-handed people is an example of what technique?
What is the main downside of controlling extraneous variables by limiting participants to a very specific category, such as 20-year-old, heterosexual, female, right-handed psychology majors?
Why are confounding variables considered undesirable in an experiment?
In the context of the chapter, what does the term 'conditions' refer to?
What is one way to avoid IQ from becoming a confounding variable, as suggested by the text, besides random assignment?
Which of the following interventions falls under the definition of a 'treatment' in psychological research?
According to the Moseley et al. study on knee surgery, what was the surprising result regarding the placebo procedure?
A research design where participants are randomly assigned to either a treatment condition or a control condition is often called a what?
What is the primary factor believed to drive placebo effects?
What does it mean for an experiment to be a 'single factor two-level design'?
In Darley and Latané's experiment, how many conditions were created by manipulating the independent variable?
What is the crucial difference between a researcher manipulating a variable and comparing groups that already differ?
If a researcher wants to study the effect of early illness experience on hypochondriasis, why is an experiment not possible?
In a hypothetical mood experiment where participants recall childhood events, how does the variability in the 'realistic noisy data' of Table 5.1 compare to the 'idealized noiseless data'?
If a study has a confounding variable, what is the consequence for the interpretation of the results?
Which of the following describes a 'treatment condition'?
The positive effect of a simulated treatment, often driven by expectations, is known as what?
What is the primary benefit of holding participant variables constant, such as by testing only 20-year-old females?
An experiment has one independent variable with four different levels. What kind of design is this?
According to the principle of informed consent as described in relation to placebo controls, what must participants be told?
What is the second way, besides adding noise, that extraneous variables can make it difficult to detect the effect of the independent variable?
When comparing a new treatment for a simple phobia, what does the text suggest as a logical alternative to a placebo control?
If IQ varies randomly across conditions in an experiment with average IQ being roughly equal in each group, how is it best described?
According to the chapter, why is it important for researchers to exert control over extraneous variables?
What does a 'no-treatment control condition' entail for the participants in that group?
In a hypothetical study, if the treatment group improves more than the no-treatment control group, why can't a researcher definitively conclude the treatment worked?
The Moseley et al. study concluded that arthroscopic lavage for osteoarthritis is not better than what?
When is a study considered to have only one independent variable?
What is the second fundamental feature of an experiment, besides manipulation of the independent variable?
What does a wait-list control condition allow researchers to compare?