Read each questions carefully and select the best answer.
Read each questions carefully and select the best answer.
Required
2 points
2
Question 1
1.
At the beginning of the school year, a high-school teacher asks every student in her classes to fill out a survey that asks for their age, gender, the number of years they have lived at their current address, their favorite school subject, and how many hours a week they work.
Which of the following best describes the types of variables that are being measured?
Required
1 point
1
Question 2
2.
Below is a dotplot of the heights of a team of high school basketball players.
For example, there is one student who is 74 inches tall (6'2").
Based on the shape of this distribution, what numerical measures would best describe it?
Required
1 point
1
Question 3
3.
Below is a dotplot of the heights of a team of high school basketball players.
For example, there is one student who is 74 inches tall (6'2").
The overall shape of this distribution is
Required
1 point
1
Question 4
4.
Below is a dotplot of the heights of a team of high school basketball players.
For example, there is one student who is 74 inches tall (6'2").
The mean of this distribution (don't try to find it) is
Required
2 points
2
Question 5
5.
A survey was conducted by a statistics student, asking 300 high school students 'How many siblings do you have?'
How should this data be displayed?
Select all the appropriate graphs below:
Required
1 point
1
Question 6
6.
Answer:
a. Which of the following are not resistant to outliers?
b. What does this mean?
Select both correct answers.
Required
1 point
1
Question 7
7.
Which of the distributions below has the smaller standard deviation?
Required
1 point
1
Question 8
8.
The five-number summary of the distribution of scores for an exam in a psychology class last semester was
Mean = 62 SD = 14 min =18 Q1 = 39 Med = 62 Q3 = 76 Max = 100.
What percent of the students had scores above 39?
Required
2 points
2
Question 9
9.
The summary statistics of the distribution of scores (in percents) for an exam in a psychology class last semester was
Mean = 62 SD = 14 min =18 Q1 = 39 Med = 62 Q3 = 76 Max = 100
Hint: Look at the boxplot that you sketched for #8, it might help.
What percent students had scores between 39 and 76?
What is this called?
Required
2 points
2
Question 10
10.
Check the values for the mean and the median in #9.
How does the mean compare to the median?
What does this tell you about the shape?
Select both answers.
Required
1 point
1
Question 11
11.
In a class of 40 students, the grades on a statistics test are summarized in the following frequency table.
Using the fact that there are 40 total students, use the frequencies in the table above to figure out where the median value is.
The median grade is which of the following scores?
Required
2 points
2
Question 12
12.
The back-to-back stem and leaf plot below gives the growth in millimeters of 23 flower bulbs planted by a 5th grade class.
The plant heights were measured after one week of growth and after two weeks of growth.
Write a few (2 or more) sentences comparing the two distributions.
Required
1 point
1
Question 13
13.
The back-to-back stem and leaf plot below gives the growth in millimeters of 23 flower bulbs planted by a 5th grade class.
The plant heights were measured after one week of growth and after two weeks of growth.
What is the median plant height after two weeks?
Required
4 points
4
Question 14
14.
A group of 78 third-grade students in a Midwestern elementary school took a “self-concept” test that measured how they felt about themselves. Higher point scores indicate more positive self-concepts.
A histogram and some summary statistics for these students' self-concept scores are given below.
What percent of the third graders scored less than 30 on the self-concept test? _______ %
Zoom in to count the number of students that scored less than 30.
Calculate the percent. Round your answer to one place past the decimal.
Interpret the standard deviation. _______
Required
5 points
5
Question 15
15.
A group of 78 third-grade students in a Midwestern elementary school took a “self-concept” test that measured how they felt about themselves. Higher point scores indicate more positive self-concepts.
A histogram and some summary statistics for these students' self-concept scores are given below.
Note: Q1 = 50 Med=59 Q3 = 65
What is the IQR? _______
What is the Outlier Rule to check if 84 is a high outlier? _______
Hint: give the formula for finding the high outlier.
What is the upper limit that we can use to check if 84 is an outlier? _______
Is 84 an outlier? explain. _______
Required
1 point
1
Question 16
16.
Use the dotplot below that shows points scored by 18 students on a Statistics quiz.
What is the percentile for the data value at 30?
Required
1 point
1
Question 17
17.
Interpret the percentile from #16.
0 points
0
Question 18
18.
BONUS: Read carefully! Worth 4 points toward your grade.
To the right is called a cumulative relative frequency plot for the scores of a large university class on a 90-point statistics.
Notice the percentiles are on the y axis and the scores are on the x axis.
These graphs can be read to understand percentile information about a data distribution.
Look at the graph carefully:
#1: A score of 50 will put a student at what percentile? _______
#2: What score will put a student at the Q1 or 25th %ile?_______