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 whether they plan to go to college after high school.
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 adult literacy rates in 177 countries in 2008, according to the United Nations.
For example, the lowest literacy rate was 23.6%, in the African country of Burkina Faso.
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 adult literacy rates in 177 countries in 2008, according to the United Nations.
For example, the lowest literacy rate was 23.6%, in the African country of Burkina Faso.
The overall shape of this distribution is
Required
1 point
1
Question 4
4.
Below is a dotplot of the adult literacy rates in 177 countries in 2008, according to the United Nations.
For example, the lowest literacy rate was 23.6%, in the African country of Burkina Faso.
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 'What is your favorite class: History, English, Spanish, Science or Mathemtatics?'
How should this data be displayed?
Select all the appropriate graphs below:
Required
1 point
1
Question 6
6.
Answer the following:
a. Which of the following are 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 larger 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 = 66 SD = 14 min =18 Q1 = 39 Med = 62 Q3 = 76 Max = 100.
Sketch a boxplot using the 5# summary in the 'show your work' area.
What percent of the students had scores below 39?
Required
2 points
2
Question 9
9.
The five-number summary of the distribution of scores for an exam in a psychology class last semester was
Mean = 66 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.
Answer both questions:
a. What percent students had scores below 62?
b. What is this value 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 of the distribution?
Select both correct answers.
Required
1 point
1
Question 11
11.
In a class of 100 students, the grades on a statistics test are summarized in the following frequency table.
Using the fact that there are 100 total students, use the frequencies in the table above to figure out where the median value is.
The median grade is in which of the following intervals?
Required
2 points
2
Question 12
12.
The back-to-back stem and leaf plot below gives the pulse rates for a group of football players both before and after a running drill.
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 pulse rates for a group of 19 football players both before and after a running drill.
What is the median for the pulse rates after the drill?
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.
Interpret the standard deviation. _______
What percent of the third graders scored 75 or higher on the self-concept test? _______ %
Zoom in to count the number of students that scored 75 or higher.
Calculate the percent. Round your answer to one place past the decimal.
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 20 is a low outlier? _______
Hint: give the formula for finding the low outlier.
What is the lower limit that we can use to check if 20 is an outlier? _______
Is 20 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 45?
Calculate the percent then round to one place past the decimal.
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 30 will put a student at what percentile? _______
#2: What score will put a student at the Q3 or 75th %ile?_______