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Started on Wednesday, 8 September 2021, 6:25 PM State Finished Completed on Wednesday, 8 September 2021, 6:31 PM Time taken 6 mins 9 secs Grade 10.00 out of 10.00 ( 100 %) Information Flag question Information text An automobile producing company operates car dealerships that sell its cars. In order to assess the service costumers get at the dealerships a team from the Customer Relationship Department was assembled. The team was sent to 20 randomly selected dealerships. Each dealership was visited once by the team for an entire working day. During a visit the team interviewed all the customers that arrived at that dealership. One of the questions that each of the customers were asked is: "Do you currently possess a car made by our company?" The answers were marked down as "Yes", "No", or "Refuse to Answer", depending on the customer's response. Select the correct answer in each of the following 4 questions:
Question 1
Correct Mark 1.00 out of 1. Flag question Question text The population in this survey is: Select one: a. The researchers that conducted the survey. b. Customers that arrive at dealerships of the company.
c. The automobile producing company. d. Owners of cars that are produced by the company. Feedback The target of the survey is to assess the service that costumers get at the dealerships. The correct answer is: Customers that arrive at dealerships of the company.
Question 2
Correct Mark 1.00 out of 1. Flag question Question text The sample in this survey is: Select one: a. The team that conducted the survey. b. Customers that arrive at dealerships of the company. c. "Yes", "No", or "Refuse to Answer". d. Customers that arrive at the selected dealerships during the day of visit. Feedback All the costumers that arrive at dealerships are the population. The subset of those that arrive to the 20 dealerships that were selected are the sample. The correct answer is: Customers that arrive at the selected dealerships during the day of visit.
Question 3
Correct Mark 1.00 out of 1.
b. The percentage, among costumers that were interviewed, of those that do not possess a car made by the company c. Customers that arrive at the selected dealerships during the day of visit. d. The team that conducted the survey. Feedback "The percentage, among costumers that were interviewed, of those that do not possess a car made by the company" is the only answer that describes a characteristic of the sample. The third answer describes the sample, not a characteristic of it: The percentage of the subset within the sample is a statistic, the sample itself is not. The correct answer is: The percentage, among costumers that were interviewed, of those that do not possess a car made by the company Information Flag question Information text The Customers Service Center of a large bank receive calls from customers. The number of incoming calls between 8:00 AM and 8:10 AM in consecutive days were recorded. The number of incoming calls during the working days of the month of September were: 8, 10, 6, 7, 12, 7, 8, 7, 8, 6, 9, 4, 6, 14, 10, 10, 10, 10, 6, 10, 12, 7 The number of incoming calls during the working days of the month of February were: 9, 11, 14, 6, 4, 6, 7, 3, 3, 2, 5, 6, 6, 5, 6, 7, 5, 4, 3, 5. Create two R objects, one by the name "Sep", and the other by the name "Feb". The first object should contain the first data and the second object should contain the second data. Produce a frequency table (with the function "table") for each of the objects and a bar plot (with the combination of the function "plot" and the function "table"). For comparison, bar plots like the one you should obtain are presented in Figure 1.6. and Figure 1.. In light of the description given above, and based on the tables and/or the plots, select the correct answer in each of the following 6 questions:
Question 5
Correct Mark 1.00 out of 1. Flag question Question text The data used to produce the tables and plots is: Select one: a. A population. b. A sample. c. A parameter. d. A statistic. Feedback The meaning of deciding that the given information is a population is that one's target in the investigation of number of arriving calls is only with respect to the specific dates and times that are described in the question. It is more likely that one has a broader interest, say the overall workload of the department. In such a case the data represents number of incoming calls at other dates and times. Hence, it is a sample. A hint in favor of the option that the data is a subset of a larger population of phone-tracking information is the sentence: "The number of incoming calls between 8:00 AM and 8:10 AM in consecutive days were recorded." The correct answer is: A sample.
Question 6
Correct Mark 1.00 out of 1. Flag question Question text
c. A statistic. d. None of the above. Feedback The difference between the averages is a characteristic of the data, a statistic. A hint that the correct answer is a statistic and not a parameter is the fact that one can compute the value of the average from the data. The correct answer is: A statistic.
Question 8
Correct Mark 1.00 out of 1. Flag question Question text In which of the months the number of incoming calls between 8:00 AM and 8:10 AM tends to be smaller? Select one: a. September. b. February. c. The number of incoming calls in both months is about the same. d. One cannot answer the question based on the given data. Feedback The distribution in the month of February tends to concentrate in the range between 2 and 7. The distribution in the month of September tends to concentrate in the range between 6 and 10. The correct answer is: February.
Question 9
Correct Mark 1.00 out of 1.
Flag question Question text The height of the fourth bar from the left of the bar plot for the month of February represents the fact that? Select one: a. In 4 of the days of the month of February there were 5 incoming calls. b. In 5 of the days of the month of February there were 4 incoming calls. c. In 4 of the days of the month of February there were 2 incoming calls. d. In 2 of the days of the month of February there were 4 incoming calls. Feedback The fourth bar from the left of the bar plot for the month of February is placed above the value "5" and its height is 4 units. The correct answer is: In 4 of the days of the month of February there were 5 incoming calls.
Question 10
Correct Mark 1.00 out of 1. Flag question Question text The location of the highest bar of the bar plot for the month of September represents the fact that? Select one: a. 5 incoming calls came during 6 days of the month of February.
Question 1
Correct Mark 1.00 out of 1. Flag question Question text What is the relative frequency of direct hits that were category 2 hurricanes? Select one: a.
b.
c.
d. Not enough information to calculate. Feedback The total of all relative frequencies is 1.000. Denote by p the relative frequency of category 2 hurricanes. Observe that 0.3993 + p + 0.2601 + 0.0659 + 0.0110 = 1. Consequently, p = 1 - 0.3993 + 0.2601 + 0.0659 + 0.0110 = 1 - 0.7363 = 0. The correct answer is: 0.
Question 2
Correct Mark 1.00 out of 1. Flag question Question text
The relative frequency of direct hits that were AT LEAST a category 3 storm
is Answer. (The numerical answer that you provide should be of the form "0.xxxx", with four digits to the right of the zero.) Feedback The relative frequency of category 3 or more is the sum of the relative frequencies of categories 3, 4 , and 5: 0.2601 + 0.0659 + 0.0110 = 0. The correct answer is: 0. Information Flag question Information text Sixty adults with gum disease were asked the number of times per week they used to floss before their diagnoses. The (incomplete) results are shown below:
Flossing Frequency for Adults with Gum Disease
# per Week Freq. Relative Freq. Cum. Relative Freq. 0 27 0. 1 18 3 0. 6 3 7 1 0. Fill in the blanks in the table and answer the next two question: (The numerical answer that you provide should be of the form "0.xxxx", with 4 digits to the right of the zero.)
Question 3
Correct Mark 1.00 out of 1. Flag question Question text The relative frequency that flossed 6 times per week is:
Flag question Question text The sample size is: Select one: a. 8 b. 9 c. 72 d. Not enough information to tell. Feedback The object "freq" contain the table of frequency of the production series, divided according to the number of malfunctioning products that they had. The cumulative frequency of all the production series that had 8 malfunctioning products or less, which includes all production series, is reported under the number "8" in the output of the expression "cumsum(freq)". This number is 72. The correct answer is: 72
Question 6
Correct Mark 1.00 out of 1. Flag question Question text The frequency of production series where there are 4 malfunctioning products is: Select one: a. 57
b. 9 c. 16 d. Not enough information to calculate. Feedback The cumulative frequency of production series that have 4 malfunctioning products or less is 57. The cumulative frequency of production series that have 3 malfunctioning products or less or less is 41. The frequency of production series that have exactly 4 production series is the difference between these two numbers: 57 - 41 = 16. The correct answer is: 16
Question 7
Correct Mark 1.00 out of 1. Flag question Question text The frequency of production series where there are less than 7 malfunctioning products is: Select one: a. 70 b. 71 c. 72 d. Not enough information to calculate. Feedback
Flag question Question text The type of the variable "id" is: Select one: a. numeric b. factor Feedback All the values are numbers. Technically, R treats this variable as a numeric sequence. However, one would typically not use this variable for statistical inference. Usually, it serves as a key, a unique identifier, in data set management. The correct answer is: factor
Question 10
Correct Mark 1.00 out of 1. Flag question Question text The type of the variable "sex" is: Select one: a. numeric b. factor Feedback Values are non-numeric: "MALE" and "FEMALE". The correct answer is: factor
Question 11
Correct
Mark 1.00 out of 1. Flag question Question text The type of the variable "diastolic" is: Select one: a. numeric b. factor Feedback All values are numeric. The correct answer is: numeric Information Flag question Information text A study was done to determine the age, type of activity, number of times per week and the duration (amount of time) of resident use of a local park in San Jose. The first house in the neighborhood around the park was selected randomly and then every 8th house in the neighborhood around the park was interviewed. Answer the following 2 questions:
Question 12
Correct Mark 1.00 out of 1. Flag question Question text "Age" is what type of data? Select one:
Flag question Question text Number of tickets sold to a concert. Select one: a. qualitative/factor b. quantitative/numeric Feedback The correct answer is: quantitative/numeric
Question 15
Correct Mark 1.00 out of 1. Flag question Question text Favorite baseball team. Select one: a. qualitative/factor b. quantitative/numeric Feedback The correct answer is: qualitative/factor
Question 16
Correct Mark 1.00 out of 1.
Flag question Question text Number of students enrolled at Evergreen Valley College. Select one: a. qualitative/factor b. quantitative/numeric Feedback The correct answer is: quantitative/numeric
Question 17
Correct Mark 1.00 out of 1. Flag question Question text Distance to the closest movie theater. Select one: a. qualitative/factor b. quantitative/numeric Feedback The correct answer is: quantitative/numeric
Question 18
Correct Mark 1.00 out of 1.
