Scatterplots
What term describes a scatterplot where the data points generally slope upwards from left to right, indicating that as one variable increases, the other variable also increases?
positive correlation
This is the specific variable that the researcher intentionally changes or manipulates to see its effect.
Independent Variable.
What happens to the experimental probability as the number of trials increases?
It gets closer to the theoretical probability
In a scatterplot comparing the amount of daily exercise in minutes (x) and a person's resting heart rate in beats per minute (y), what is the independent variable?
The amount of daily exercise
This is an inactive substance or fake treatment given to a control group to account for the psychological expectation of feeling better.
Placebo
A bag contains 3 red marbles, 2 blue marbles, and 5 green marbles. What is the theoretical probability of drawing a blue marble?
1/5 or 20%
What specific term refers to a data point on a scatterplot that sits far away from the rest of the observed data points?
Outlier
Factors in an experiment that are intentionally kept the same so they do not influence the results.
Controlled variables (constants
You roll a fair six-sided die 30 times. How many times should you theoretically expect the number 3 to appear?
5 times
If a scatterplot has a line of best fit with the equation y= -2x + 15, what is the predicted (y)-value when the (x)-value is (4)?
7
his specific technique is used to account for pre-existing lurking variables by dividing a sample into groups (e.g., male and female) before randomly assigning participants to treatment and control conditions.
Blocking (or randomized block design)
In an experiment involving a 6-sided die rolled 600 times, a "3" was rolled 120 times. Compare the experimental probability to the theoretical probability, which one is higher?
The experimental probability is higher
A scatterplot shows a strong positive correlation between ice cream sales and forest fire rates. Why is it statistically incorrect to conclude that eating ice cream causes forest fires?
Confounding variables (or a lurking variable). Both variables are independently driven by a third variable: high summer temperatures.
To prevent bias in medical research, this type of trial is used in which neither the patients nor the researchers know who is receiving the actual treatment and who is getting the placebo.
Double-blind study
John pulls a marble out of the same bag (3 red, 2 blue), records the color, and puts it back 50 times. He pulls a blue marble 22 times. What is the experimental probability?
11/25 or 44%