Download Review Questions

Review Questions.
1. Classify each data description and state your reasoning.
a. Eye color – categorical
b. Weight of a pig- continuous
c. Number of times you visit the bathroom in a day- disccrete
2. Give an example of each of the following
a. Observational study – watching birds fly
b. Experimental study-adding acid to a base to watch it explode
c. Experimental and double blind study –drug study where know one knows
what will happen
3. Give an example of a study and a bias that can occur for the study.
Asking all people who the best pitcher is in baseball. Some people have a life
and don’t know anything about baseball.
4. Given the data below find each of the following.
1.3, 4.3, 5.2, 5.4 ,6.7,6.9, 7.2, 9.6
a. Minimum -1.3
b. Q1-4.75
c. Median-6.05
d. Q3-7.05
e. Maximum-9.6
f. Mean-5.825
g. Mode-none
h. Dot plot
i.
Histogram
j.
Box-and-whiskers
k. Stem-and-leaf
l. Standard deviation-2.275
m. Variance-5.175
5.
6.
7.
8.
9.
n. Determine if there is an outlier. State the effect of any outlier on the mean
and standard deviation. There is an outlier on both ends . The new mean
ins 5.95 and the new standard deviation is 1.05
o. Can you do a bar graph with this data? Why or Why not? No, Not
categorical data
What would happen to a normal curve if the standard deviation becomes larger?
It would flatten out because the average distance from the mean became
greater.
What happens to the area? Nothing, it would remain 1 because 100% of the data
is under the curve
What is the difference between variance and standard deviation? Standard
deviation is the square root of the variance
What is standard deviation? The average distance of each data point from the
mean
Create a dot plot that is skewed. Using at least 7 points. Tell me how it is
skewed . List your points and state the relationship between the mean and the
median.
Use the empirical rule to answer the following.
The average weight of a mini dachshund is 9 lbs. The standard deviation is 0.5
lbs. You have a sample of 1500 mini dachshunds.
a. Construct the axis for the normal curve
7.5
8
8.5
9
9.5
10
10.5
b. What percent of mini dachshunds are found?
i. Between 8 and 10 pounds 95%
ii. Between 7.5 and 9.5 pounds. 83.85%
iii. Greater than 10.5 pounds? .15%
c. How many dogs in your sample are between 8 and 9.5 pounds? 1222.5
d. If my dog weighs 11.3 pounds what is his z-score? 4.6
e. If my mom’s dog weighs 8.32 pounds what is her z-score? -1.36
f. Which dog is closer to the mean? My mom’s dog
10. How can you use z-score to compare two or more set of data? A z-score shows
you how close you are to the mean. The mean does not matter.