BackStep-by-Step Study Guide for Descriptive Statistics Exam
Study Guide - Smart Notes
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Q1. In the study, community college students are the:
Background
Topic: Populations and Samples in Statistics
This question tests your understanding of the difference between a population and a sample in a statistical study.
Key Terms:
Population: The entire group that you want to study or draw conclusions about.
Sample: A subset of the population that is actually observed or measured.
Step-by-Step Guidance
Read the scenario carefully: Bob is interested in how much community college students work outside of school.
Identify who Bob wants to learn about (all community college students) versus who he actually studies (students in his psychology class).
Recall that the population is the larger group of interest, while the sample is the group actually observed.
Try solving on your own before revealing the answer!
Final Answer: Population
Community college students are the population because Bob wants to generalize his findings to all students, not just those in his class.
Q2. In the study, Bob's psychology class is the:
Background
Topic: Populations and Samples
This question tests your ability to identify the sample in a study.
Key Terms:
Sample: The group of individuals actually observed or measured in the study.
Step-by-Step Guidance
Review the scenario: Bob collects data from his psychology class.
Determine which group is actually being measured (his psychology class).
Recall that the sample is the group from which data is collected.
Try solving on your own before revealing the answer!
Final Answer: Sample
Bob's psychology class is the sample because it is the group he actually collects data from.
Q3. Bob is collecting:
Background
Topic: Types of Data Collection
This question tests your understanding of observational studies versus experiments.
Key Terms:
Observational Study: The researcher observes and records data without manipulating variables.
Experiment: The researcher manipulates variables to observe effects.
Step-by-Step Guidance
Consider whether Bob is manipulating any variables or just recording information.
Recall that observational studies involve recording data as it occurs naturally.
Determine if Bob is simply observing or if he is conducting an experiment.
Try solving on your own before revealing the answer!
Final Answer: Observational Data
Bob is collecting observational data because he is not manipulating any variables, just recording information.
Q4. Justify your answer for #3: How do you know?
Background
Topic: Justifying Observational Studies
This question asks you to explain your reasoning for identifying the study as observational.
Key Terms:
Manipulation: Changing or controlling variables in an experiment.
Observation: Recording data without intervention.
Step-by-Step Guidance
Review the scenario and confirm that Bob is not changing any conditions or variables.
Explain that observational studies do not involve manipulation, only recording what naturally occurs.
Use evidence from the scenario to support your justification.
Try solving on your own before revealing the answer!
Final Answer: Bob is not manipulating any variables, so it is observational.
He is simply recording how many hours students work, without changing anything about their environment.
Q5. Music would be the ______ variable.
Background
Topic: Variables in Experiments
This question tests your ability to identify independent and dependent variables in an experiment.
Key Terms:
Independent Variable: The variable that is intentionally changed or manipulated by the researcher.
Dependent Variable: The variable that is measured or observed in response to changes in the independent variable.
Step-by-Step Guidance
Read the scenario: Ella wants to know if plants grow faster when they listen to Taylor Swift music.
Identify what Ella is changing (music exposure) and what she is measuring (plant height).
Recall that the independent variable is what the researcher manipulates.
Try solving on your own before revealing the answer!
Final Answer: Independent Variable
Music is the independent variable because Ella is intentionally changing whether plants are exposed to music.
Q6. Plant height would be the ______ variable.
Background
Topic: Variables in Experiments
This question tests your ability to identify the dependent variable in an experiment.
Key Terms:
Dependent Variable: The variable that is measured to see if it changes in response to the independent variable.
Step-by-Step Guidance
Review the scenario: Ella measures the height of each plant after the experiment.
Recall that the dependent variable is what is measured as the outcome.
Identify plant height as the variable being measured.
Try solving on your own before revealing the answer!
Final Answer: Dependent Variable
Plant height is the dependent variable because it is what Ella measures to see the effect of music.
Q7. Ella is using a ______.
Background
Topic: Types of Studies
This question tests your ability to distinguish between experimental and observational studies.
Key Terms:
Experiment: A study in which the researcher manipulates one variable to observe its effect on another variable.
Observational Study: A study in which the researcher observes subjects without manipulating variables.
Step-by-Step Guidance
Determine if Ella is manipulating any variables (music exposure).
Recall that experiments involve manipulation and control.
Identify whether the study is experimental or observational based on the scenario.
Try solving on your own before revealing the answer!
Final Answer: Experiment
Ella is conducting an experiment because she is intentionally manipulating the music variable to observe its effect on plant growth.
Q8. Justify your answer for #7: How do you know?
Background
Topic: Justifying Experimental Studies
This question asks you to explain your reasoning for identifying the study as an experiment.
Key Terms:
Manipulation: Changing or controlling variables in an experiment.
Control: Keeping other variables constant to isolate the effect of the independent variable.
Step-by-Step Guidance
Review the scenario and confirm that Ella is intentionally changing the music variable.
Explain that experiments involve manipulation and control of variables.
Use evidence from the scenario to support your justification.
Try solving on your own before revealing the answer!
Final Answer: Ella intentionally manipulates the music variable.
This makes it an experiment because she controls the conditions to observe the effect on plant height.
