Comp Sci Unit 3 #4

A small team of wildlife researchers is working on a project that uses motion-activated field cameras to capture images of animals at study sites. The team is considering using a “citizen science” approach to analyze the images. Which of the following best explains why such an approach is considered useful for this project?

• Distributed individuals are likely to be more accurate in wildlife identification than the research team.

• The image analysis is likely to be more consistent if completed by an individual citizen.

• The image analysis is likely to require complex research methods.

• The image analysis is likely to take a longer time for the research team than for a distributed group of individuals.

Which of the following activities is most likely to be successful as a citizen science project?

• Collecting pictures of plants from around the world that can be analyzed to look for regional differences in plant growth.

• Designing and building a robot to help with tasks in a medical laboratory.

• Sorting scientific records and removing duplicate entries in a database with a large number of entries.

• Using a simulation to predict the impact of a construction project on local animal populations.

The table below shows the time a computer system takes to complete a specified task on the customer data of different-sized companies.

Based on the information in the table, which of the following tasks is likely to take the longest amount of time when scaled up for a very large company of approximately 100,000 customers?

• 
  Backing up data

• Deleting entries from data

• Searching through data

• Sorting data

Directions: The question or incomplete statement below is followed by four suggested answers or completions. Select the one that is best in each case.

A social media site allows users to send messages to each other. A group of researchers gathered user data for the first 10 years of the site’s existence. Some of the data are summarized in the table below, along with some of the company milestones.

Which of the following hypotheses is most consistent with the data in the table?

• The mobile app release did not have any effect on the average number of daily messages sent per user.

• The mobile app release discouraged new user registration on the site.

• The mobile app release led to users being less frequently active on the site.

• The mobile app release led to users tending to write shorter messages.

A city maintains a database of all traffic tickets that were issued over the past ten years. The tickets are divided into the following two categories.

• -Moving violations

• -Nonmoving violations

The data recorded for each ticket include only the following information.

• -The month and year in which the ticket was issued

• -The category of the ticket

Which of the following questions CANNOT be answered using only the information in the database?

• Have the total number of traffic tickets per year increased each year over the past ten years?

• In the past ten years, were nonmoving violations more likely to occur on a weekend than on a weekday?

• In the past ten years, were there any months when moving violations occurred more often than nonmoving violations?

• In how many of the past ten years were there more than one million moving violations?

An Internet service provider (ISP) is considering an update to its servers that would save copies of the Web pages most frequently visited by each user.

Which of the following is LEAST likely to occur as a result of the update?

• Average response time for user requests might decrease.

• 
  Privacy of users might be negatively affected.

• Storage requirements for the servers might increase.

• Web sites that are not visited frequently might no longer be accessible to users.

Directions: The question or incomplete statement below is followed by four suggested answers or completions. Select the one that is best in each case.

Computers are often used to search through large sets of data to find useful patterns in the data. Which of the following tasks is NOT an example where searching for patterns is needed to produce useful information?

• A credit card company analyzing credit card purchases to identify potential fraudulent charges

• A grocery store analyzing customers’ past purchases to suggest new products the customer may be interested in

• A high school analyzing student grades to identify the students with the top ten highest grade point averages

• An online retailer analyzing customers’ viewing habits to suggest other products based on the purchasing history of other customers

Which of the following applications is most likely to benefit from the use of crowdsourcing?

• An application that allows users to convert measurement units (e.g., inches to centimeters, ounces to liters)

• An application that allows users to purchase tickets for a local museum

• An application that allows users to compress the pictures on their devices to optimize storage space

• An application that allows users to view descriptions and photographs of local landmarks

Directions: The question or incomplete statement below is followed by four suggested answers or completions. Select the one that is best in each case.

A social media site allows users to send messages to each other. A group of researchers gathered user data for the first 10 years of the site’s existence. Some of the data are summarized in the table below, along with some of the company milestones.

The researchers noticed that the total number of registered users appears to be increasing at about a constant rate. If this pattern continues, which of the following best approximates the total number of registered users, in millions, in year 12 (two years after the last entry in the table) ?

• 
  30.6

• 31.2

• 31.8

• 
  32.4

A student’s overall course grade in a certain class is based on the student’s scores on individual assignments. The course grade is calculated by dropping the student’s lowest individual assignment score and averaging the remaining scores.

For example, if a particular student has individual assignment scores of 85, 75, 90, and 95, the lowest score (75) is dropped. The calculated course grade is (85+90+95)/3=90.

An administrator at the school has data about hundreds of students in a particular course. While the administrator does not know the values of each student’s individual assignment scores, the administrator does have the following information for each student.

• -The student name

• -A unique student ID number

• -The number of assignments for the course

• -The average assignment score before the lowest score was dropped

• -The course grade after the lowest score was dropped

Which of the following CANNOT be determined from this data alone?

• For a given student, the value of the highest assignment score

• For a given student, the value of the lowest assignment score

• For a given student, the change in course grade as a result of dropping the lowest score

• The proportion of students who improved their course grade as a result of dropping the lowest score