Distribution
Miscellaneous
Position
Sampling & Experimentation
Bivariate Data
100
What city distribution has the largest range?
City A
100
What is the shape of this distribution?
Skew Left
100
What is z-score?
The amount of standard deviations above/below the mean.
100
What are all the types of random sampling?
a. Simple random sampling
b. Stratified Sampling
c. Cluster Sampling
d. Systematic Sampling
100
The difference between the points in the scatter plot and the LSRL is known as?
Residuals
200
Which of the following should be used to describe the center of this distribution?
A. Mean, because it is an unbiased estimator
B. Median, because the distribution is skewed
C. IQR, because it excludes outliers and includes only the middle 50 percent of data
D. First quartile, because the distribution is left skewed
E. Standard deviation, because it is unaffected by the outliers
B. Median, because the distribution is skewed
200
Use the following computer output for a least-squares regression for Questions below.
What is the equation of the least-squares regression line?
A. ŷ= -0.6442x+ 22.94
B. ŷ= 22.94 + 0.5466x
C. ŷ= 22.94 + 2.866x
D. ŷ= 22.94 - 0.6442x
E. ŷ= -0.6442 + 0.5466x
A. ŷ= -0.6442x+ 22.94
200
During flu season, a city medical center needs to keep a large supply of flu shots. A nurse’s aid compiles data on the number of flu shots given per day in the past few years during flu season. A cumulative probability chart of the collected data is as follows:
How many flu shots should the center store every day to meet the demand on 95 percent of the days?
A. At most 190
B. At most 140
C. Exactly 170
D. At least 150
E. At least 200
E. At least 200
200
A researcher is interested in the weight of land iguanas. First, he separates the available iguanas by gender. Then he randomly selects 20 male iguanas and 20 female iguanas. What type of sampling is this?
Stratified Random Sampling
200
What is the LSRL equation of this computer output?
y=-.2179x+38.929
300
Which distribution had the closest mean and median?
Station 2
300
What is the age of the 1st quartile of the distribution?
10 years
300
If I tell you that you scored at the 55th percentile on your final exam, you would know:
55% of the class scored the same or worse than you did
You earned a 55% on the exam
You failed the exam
45% of the class scored worse than you did
55% of the class scored the same or worse than you did
300
What type of experiment design does the tree diagram below show?
Randomized Block Design
300
Commercial airlines need to know the operating cost per hour of flight for each plane in their fleet. In a study of the relationship between operating cost per hour and number of passenger seats, investigators computed the regression of operating cost per hour on the number of passenger seats. Interpret the y-intercept of the problem using the computer output below:
When the seats is 0 the predicted operating cost per hour is $1136
400
The average number of calories in Yum-Yum Good candy bars is 210, with a standard deviation of 10. If I multiplied the calories by 10 and added 15. What is the new standard deviation?
100
400
In a group of 10 scores, the largest score is increased by 40 points. What will happen to the mean? Increase OR Decrease OR Stay the same
Increase
400
The observed times (in minutes) it takes a runner to complete a marathon are normally distributed. The z-score for his running time this week is –2. Which one of the following statements is a correct interpretation of his z-score?
A. This week his time was two minutes lower than his time last week.
B. This week his time was two minutes lower than his best time ever.
C. This week his time was two minutes lower than his average time.
D. This week his time was two standard deviations lower than his average time.
E. This week his time was two standard deviations lower than his time last week
D. This week his time was two standard deviations lower than his average time.
400
What are the experimental units and the treatments of the experimental design below?
Experimental Units: 1200 subjects
Treatments: Drug x 325 mg and Placebo
400
B. On average there is a predicted increase of 19.0 ppm in concentration of zinc for every increase of 1 ppm in concentration of lead found in the fish.
500
The following boxplot summarizes the prices of books at a bookstore.
Which of the following is true about the prices of books at this store?
A. This store carries more books priced above the mean than below the mean.
B. This store carries more books priced below the mean than above the mean.
C. This store carries about the same number of books at different prices in the entire price range.
D. The mean price of books at this store is the same as the median price of books.
E. The mean price of books at this store is lower than the median price of books.
B. This store carries more books priced below the mean than above the mean.
500
A teacher believes that giving her students a practice quiz every week will motivate them to study harder, leading to a greater overall understanding of the course material. She tries this technique for a year, and everyone in the class achieves a grade of at least C. Is this an experiment or an observational study?
A. An experiment, but with no reasonable conclusion possible about cause and effect
B. An experiment, thus making cause and effect a reasonable conclusion
C. An observational study, because there was no use of a control group
D. An observational study, but a poorly designed one because randomization was not used
E. An observational study, and thus a reasonable conclusion of association but not of cause and effect
B. An experiment, thus making cause and effect a reasonable conclusion
500
There is 20 digits, what is the percentile of the digit 10?
16/20 = 80%
500
In a experiment, the primary purpose of blocking is to:
Reduce the within treatment bias
Reduce the between treatment variation
Reduce bias
Eliminate confounding variables
Eliminate confounding variables