statistics 1 - estatítica gabarito

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Curso Estatística 
Teste Atividade - Statistics 1 
Iniciado 21/06/19 10:35 
Enviado 21/06/19 11:23 
Status Completada 
Resultado da tentativa 6 em 10 pontos 
Tempo decorrido 47 minutos 
Resultados exibidos Respostas enviadas, Respostas corretas, Comentários 
• Pergunta 1 
1 em 1 pontos 
 
Skills: Identify subjects and variablesGenerate numerical measures of center of spread of the 
distribution of a quantitative variable and use them to summarize the distribution. 
"multiple choice" question: select the correct answer. Here again, is the distribution of number 
hours for exercise per week of 50 male college student: 
If the largest observation (23 hours) was wrongly recorded as 230 hours. How would that effect 
the mean, median and the standard deviation of this distribution? 
 
Resposta 
Selecionada: 
 
The mean and standard deviation will increase, but the median will not 
change. 
Resposta Correta: 
The mean and standard deviation will increase, but the median will not 
change. 
Feedback da 
resposta: 
This is correct. The mean and standard deviation are affected by outliers (and 
therefore will increase), but the median is not affected by outliers and 
therefore will not change. 
 
 
• Pergunta 2 
1 em 1 pontos 
 
Questions 1-3 are related to the following information: 
A college professor records the following information for each of the 55 students enrolled in her 
class: 
• Gender 
• Year (Freshman, Sophomore, Junior, Senior) 
• Number of missed classes 
• Midterm score 
• Extra credit (1 – Submitted, 2 – Not submitted) 
• Final exam score 
 
Skills: Understand the structure of a data set and identify different type of variables.Identify 
subjects and variables 
"multiple choice" question: select the correct answer. 
Which of the following is a categorical variable? 
 
Resposta Selecionada: 
Extra credit (1 – Submitted, 2 – Not submitted) 
Resposta Correta: 
 
Extra credit (1 – Submitted, 2 – Not submitted) 
Feedback da resposta: This is correct. 
 
• Pergunta 3 
0 em 1 pontos 
 
Question 6—11 are related to the following information:The histogram below displays the 
distribution of the number of hours of exercise per week for 50 male college students: 
 
Skills: Generate graphical displays of the distribution of a quantitative variable and use them to 
summarize the overall pattern of the distribution.Identify subjects and variables 
"multiple choice" question: select the correct answer. What percentage of the students exercise 
less than 9 hours per week? 
 
 
Resposta Selecionada: 
32% 
Resposta Correta: 
64% 
 
 
• Pergunta 4 
0 em 1 pontos 
 
Skills: Generate graphical displays of the distribution of a quantitative variable and use them to 
summarize the overall pattern of the distribution. Identify subjects and variables 
"multiple choice" question: select the correct answer. 
Here again, is the side-by-side boxplots that display the delivery time distributions (in minutes) 
of two pizza shops – “Big Slice” and “City Pizza” 
 
 
 
Which pizza shop has a larger percentage of deliveries that take between 25 and 35 minutes? 
 
Resposta Selecionada: 
Big Slice 
Resposta Correta: 
City Pizza 
 
 
• Pergunta 5 
0 em 1 pontos 
 
Skills: Summarize the distribution of a categorical variable. Identify subjects and variables 
"multiple choice" question: select the correct answer. A June 2017 poll asked a random sample 
of 2,500 U.S. adults the following question:Which comes closest to your view about the 2010 
health care law (Obamacare)? The law is working well and should be kept in place as is;There 
are some good things in the law, but some changes are needed to make it work better;The law 
has so much wrong with it that it needs to be repealed entirely.The following pie-chart 
represents the distribution of responses: 
 
 
Which of the following statements is true regarding what we can learn from the above 
distribution? 
Resposta 
Selecionada: 
 
More than half of U.S. adults feel that changes are needed to the 2010 
healthcare law. 
Resposta Correta: 
All of the above statements are true. 
 
 
• Pergunta 6 
0 em 1 pontos 
 
Skills: Compare distributions 
Identify subjects and variables 
Interpret boxplots 
"multiple choice" question: select the correct answer. 
 
Which gender has a larger range of SSHA scores? 
 
Resposta Selecionada: 
Females 
Resposta Correta: 
Males 
 
 
• Pergunta 7 
1 em 1 pontos 
 
Skills: Identify subjects and variablesGenerate numerical measures of center of spread of the 
distribution of a quantitative variable and use them to summarize the distribution. 
"multiple choice" question: select the correct answer. Here again, is the distribution of number 
hours of exercise per week for 50 male college student: 
 
What do you expect the relationship between the mean and the median of this distribution to 
be? 
 
Resposta Selecionada: 
The mean will be larger than the median 
Resposta Correta: 
The mean will be larger than the median 
 
 
• Pergunta 8 
1 em 1 pontos 
 
Skills: Identify subjects and variablesGenerate numerical measures of center of spread of the 
distribution of a quantitative variable and use them to summarize the distribution. 
"multiple choice" question: select the correct answer. Here again, is the distribution of number 
hours of exercise per week for 50 male college student: 
 
What are appropriate numerical measures of center and spread in this case? 
 
Resposta Selecionada: 
None of the above. 
 
Resposta Correta: 
None of the above. 
Feedback da 
resposta: 
This is correct. Since the distribution is skewed right (with one possible high 
outlier), the appropriate numerical measure of center and spread are the 
median and IQR. 
 
• Pergunta 9 
1 em 1 pontos 
 
Questions 1-3 are related to the following information: 
A college professor records the following information for each of the 55 students enrolled in her 
class: 
• Gender 
• Year (Freshman, Sophomore, Junior, Senior) 
• Number of missed classes 
• Midterm score 
• Extra credit (1 – Submitted, 2 – Not submitted) 
• Final exam score 
 
Skills: Understand the structure of a data set and identify different type of variables.Identify 
subjects and variables 
"multiple choice" question: select the correct answer. How many variables are there in this 
dataset? 
 
Resposta Selecionada: 
6 
Resposta Correta: 
6 
Feedback da resposta: This correct. 
 
 
• Pergunta 10 
1 em 1 pontos 
 
Skills: Compare distributions 
Identify subjects and variables 
Interpret boxplots "multiple choice" question: select the correct answer. 
What is the approximate median SSHA score for each gender? 
 
Resposta Selecionada: 
Females = 153, Males =114 
Resposta Correta: 
Females = 153, Males =114 
Feedback da 
resposta: 
Correct! You would use the horizontal line in each box to estimate the 
median. Good job!