Sampling Technique
Dr. Pat picks 10 random seniors, juniors, sophomores, and freshmen for a questionnaire. Name the sampling method.
What is Stratified Random Sample?
A survey is sent out to random mailing addresses throughout King of Prussia to find people's views about the new high school?
What is undercoverage?
When a point on a scatterplot has a negative residual, the predicted value is _____________ than the actual value. (higher/lower)
What is higher?
An R^2 value of 0.8532 means that _______% of the variation in one variable can be explained by the variation in the other variable.
What is 85.32%?
This is the percent of data that lies between a z-score of -1 and a z-score of 1.
What is 68%?
A paper company pulls 5 reams of paper off the assembly line at random and inspects all of the pieces of paper in the ream. Name the sampling method.
What is a cluster sample?
Maria wants to survey members of her team on her performance as their manager. She holds an individual meeting with each of her team's members and asks them the same set of questions.
What is response bias?
A regression equation for a scatterplot is shown below.
y = 2.5 + 8.3x
An actual value in this data set is (5, 40). This is the residual for this data point.
What is -4?
If a scatterplot has an R^2 value of 0.563, this is the value of the correlation coefficient (r).
What is 0.75?
A student surveyed her peers to determine how many hours they spend on social media each day. The mean for this data set was 3.2 hours and the standard deviation was 0.63 hours.
Amelia spends 2.5 hours per day on social media. This is her z-score.
What is z = -1.11?
A pollster interviews every fourth person who walks into a polling station.
What is a systematic random sample?
Caroline conducts a SRS of 100 students and only 80 students respond to her email.
What is non-response bias?
A residual plot looks like this in a scatterplot in which a linear model is appropriate.
What is scattered/random?
We cannot determine if a linear model is appropriate from only checking the r and R^2 values. We must also check the ____________________________.
What is residual plot?
A student surveyed her peers to determine how many hours they spend on social media each day. The mean for this data set was 3.2 hours and the standard deviation was 0.63 hours.
Lars has a z-score of 1.8. How many hours per day does he spend on social media?
What is 4.33 hours?
A store prints a request on each receipt asking customers to fill out a satisfaction survey online if they are willing.
What is a voluntary response survey?
A principal used the school roster to poll a random sample of 28 students, and only 10%, percent said that they ever had their phone out during class.
What is response bias?
The regression equation for a scatterplot is shown below:
y = -2.386 + 5.61 log(x)
This is the predicted value for y when x = 12.
What is 3.67?
By removing an outlier, the R2 value of a scatterplot will ________________ (increase, decrease, stay the same).
What is increase?
This percent of data lies below a data point with a z-score of -1.
What is 15.9%?
An airline company wants to survey its customers one day, so they randomly select 555 flights that day and survey every passenger on those flights.
What is a cluster random sample?
You decide to conduct a survey about the quality of food served in the school cafeteria by randomly selecting students as they leave the cafeteria after lunch on a specific day next week.
What is undercoverage?
The regression equation for a scatterplot is shown below:
log(y) = 5.121 + 2.3x
This is the predicted value for y when x = -2.
What is 3.32?
By removing a high leverage point, the r2 values of a scatterplot will ________________ (increase, decrease, stay the same).
What is stay the decrease?
A scientist measured the heights of sunflowers in inches in the month of August. Later he converted the heights to feet. One particular sunflower had a z-score of z = 2.2 when measured in inches.
This is the z-score of the flower when measured in feet.
What is z = 2.2?