Write a good hypothesis and justify why it is good.
Tomato plants that are exposed to longer periods of sunlight have an increased number of flowers." This hypothesis is good because it is testable; one can design an experiment in which different tomato plants are exposed to different periods of sunlight,
Distinguish between the independent and the dependent variable in an experiment. Give an example.
An independent variable has factors that may cause a change in the dependent variable�the part of the experiment that is often manipulated by the researcher. The dependent variable is the variable of interest in the experiment�in math, it depends on other
Identify the variables in the experiment below; all the variables.
Be able to tell what variables are in a study
Independent: what you can control
Control: stays constant
Why isn't high correlation enough to establish causation?
High correlation is not enough to establish causation because no matter how correlated two variables may be, the relationship between them may only occur by pure coincidence, such as the unusually high correlation between films Nicholas Cage appears in an
What does the "validity" of an experiment refer to?
Validity refers to how well supported the conclusion drawn from an experiment is. One of the fundamental tasks of research is to ensure the validity of your experimental procedures and conclusions.
List and briefly describe the different types validity.
The types of validity are internal, external, construct, and statistical.
Internal validity is concerned with how accurate the causal relationship between the independent and dependent variable is; it looks at whether or not confounding variables have imp
I set up a blind to observe the behavior of lions. What type validity might this threaten? Explain.
Internal validity may be threatened, because the fact that a blind has been setup near the lion's habitat may affect the behavior of the lions themselves; they may act differently because an unknown structure had been set up in their territory.
The results of an experiment in which teaching method is the experimental treatment, used with a class of low achievers, do not generalize to heterogeneous ability students. What type of threat to validity would this be? Explain.
This situation is a threat to external validity, which measures if the results of a study can be applied to external groups outside of the ones tested for during the study. Since only low achievers were used in the study, there is no evidence that the tea
In a physical performance experiment, the pre-test clues the subjects to respond in a certain way to the experimental treatment that would not be the case if there were no pre-test. What type of threat to validity would this be? Explain
It is a threat to construct validity because the method being used to construct the experiment allows for the results to be altered. The pretest is influencing the people to respond to the experiment the way the scientists conducting it want it to be so t
Give an example situation where a researcher's experimental design does not show good internal validity.
A scientist wanted to test the effects of yawning in front of other people. In doing this experiment, he picked males ages 20-22. He then placed them in front of individuals trained to yawn every ten seconds, the same way every time. He observed to see ho
Give an example situation where a researcher's experimental design does not show good construct validity.
A scientist wanted to test the miles per gallon gas consumption of the same model car made during different years by testing their 0-80 mph speeds.
A researcher conducted a study about female self-esteem in high school. The subject guessed the intent of t
I wanted to study the mating behavior of a species of rock iguana in their natural habitat. What are variables I would need to control for?
Variables that would need to be taken accountable for: location, temperature, amount of iguanas present at a given time in a given area, season, ratio of males and females, food availability (it may affect their aggression).
What does it mean when we say that an investigation has a high level of constraint? Give an example.
An investigation that has a high level of constraint typically has very specific findings, refined ideas, detailed procedures, and may aim to find a causal relationship. Example: when testing for plant growth and how it's related to the color of light it
What is the difference between a correlational study and an experimental study?
A correlational study focuses on quantifying the relationship between multiple variables, while an experimental study focuses on comparing the same variables under different, controlled conditions.
Give an example of a type of investigation that would have a high level of constraint.
For example, experimental is high constraint, so if I did an experiment on male beta fish and aggression in correlation to a small dose of a drug, this would be an example that would have high constraint, due to the fact that I could rule out data easily
What are strengths and weaknesses to having a high level of constraint?
Strengths to having a high level of constraint include high confidence in cause-and-effect relationships and that results are not confounded. Weaknesses to high constraint include findings not being applicable outside the experimental setting and less con
Give an example of a type of investigation what would have a low level of constraint.
A low constraint example would be a naturalistic experiment. Instead of measuring and manipulating variables to find answers to specific questions, the goal is to just observe what happens. For example, if I went to the desert and decided to observe rattl