Sophia Intro to Stats Unit 1 Milestone 1.A hunter is practicing his aim using a practice target. He takes 5 shots. All 5 shots hit the target, but they do
... [Show More] not hit or surround the bullseye. In addition, all 5 shots are
very spread apart on the target.
Classify the hunter's accuracy and precision.
Low accuracy and low precision
High accuracy and low precision
Low accuracy and high precision
High accuracy and high precision
RATIONALE
Since the arrows fall away from the bullseye and are spread out we would classify this as low accuracy and low precision.
CONCEPT
Accuracy and Precision in Measurements
2
A team of researchers want to measure the distance covered while driving compared to a car's driving speed.
Which statement is correct?
The speed of the car is a confounding variable.
The speed of the car is a dependent variable.
The speed of the car is an explanatory variable.
The speed of the car is a response variable.
RATIONALE
The outcome is the response, dependent or y -variable. The variable that explains the response is the explanatory, independent or x-variable. In this case the explanatory
variable is speed with distance being the response.
CONCEPT
Variables
3
Which of the following data types will be continuous?
The number of cars in 100 households
The total weight of apples harvested in the farm in a season
The letter grades students received on a class quiz
The number of children younger than ten that visited a planetarium last week
RATIONALE
The total weight of apples can take on any value and is therefore continuous. The other measures can only take on a limited number of values and are discrete.
CONCEPT
Discrete vs. Continuous Data
4
Researchers want to study the effects of classical music and memory. One group of participants will take a memory test with classical music playing in the background,
while the other group will take the memory test in complete silence. It is believed that age has an effect on memory.
Which of the following would work best to test if classical music has an effect on memory?
A completely randomized design experiment
A matched-pair design experiment
A case-control observational study
A randomized block design experiment
RATIONALE
In order to control for age in the study, by matching participants on age they can control for the affect of age on the outcome. So a matched-pair design would be most
appropriate.
CONCEPT
Matched-Pair Design
5
A grocery store owner asked the first 20 children who visited the store one day about their favorite snack.
This is what type of sampling?
Stratified sampling
Convenience sampling
Systematic sampling
Voluntary response sampling
RATIONALE
Recall that convenience samples are samples taken due to their ease of gathering information. Since he simply asked the first 20 children, this is an example of that.
Convenience samples are generally biased as they probably don't represent the entire set of interest. [Show Less]