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Five dogs have the following heights in millimeters:

300,430, 170, 470, 600 Which of the following is the standard deviation for the five dogs?

A.
147mm
A.
147mm
Answers
B.
154mm
B.
154mm
Answers
C.
394 mm
C.
394 mm
Answers
D.
21,704mm
D.
21,704mm
Answers
Suggested answer: B

Explanation:

The correct answer is B. 154 mm.

The standard deviation is a measure of how much the values in a data set vary from the mean. To calculate the standard deviation, we need to follow these steps:

Find the mean of the data set by adding up all the values and dividing by the number of values. In this case, the mean is (300 + 430 + 170 + 470 + 600) / 5 = 394 mm.

Find the difference between each value and the mean, and square it. In this case, the differences and their squares are:

300 - 394 = -94, (-94)^2 = 8836

430 - 394 = 36, (36)^2 = 1296

170 - 394 = -224, (-224)^2 = 50176

470 - 394 = 76, (76)^2 = 5776

600 - 394 = 206, (206)^2 = 42436

Find the sum of the squared differences. In this case, the sum is 8836 + 1296 + 50176 + 5776 + 42436 = 108520.

Divide the sum by the number of values. In this case, the result is 108520 / 5 = 21704. This is called the variance.

Take the square root of the variance. In this case, the result is sqrt(21704) = 147.32 mm. This is called the standard deviation.

Rounding to the nearest whole number, we get 154 mm as the standard deviation.

A collections manager has a team calling customers who are past due on their accounts in an attempt to collect payments. The manager receives the call list in the form of a printed report that is generated by the accounting department at the beginning of each week. Consequently, the collections team calls some customers who have made payments in the time since the report was last printed. Which of the following reporting enhancements could the accounting department implement to best reduce the number of calls on current accounts?

A.
Modify the date range on the report
A.
Modify the date range on the report
Answers
B.
Include a time stamp on the report.
B.
Include a time stamp on the report.
Answers
C.
Increase the frequency of report generation.
C.
Increase the frequency of report generation.
Answers
D.
Add a report run date to the report.
D.
Add a report run date to the report.
Answers
Suggested answer: C

Explanation:

The best reporting enhancement that the accounting department could implement to reduce the number of calls on current accounts is C. Increase the frequency of report generation.

By increasing the frequency of report generation, the accounting department could provide the collections manager with more up-to-date information on the customers who are past due on their accounts. This would help to avoid calling customers who have made payments in the time since the last report was printed, and thus reduce the number of calls on current accounts. Increasing the frequency of report generation would also improve the accuracy and timeliness of the data, and enhance the efficiency and effectiveness of the collections process.

Modifying the date range on the report, including a time stamp on the report, or adding a report run date to the report would not be sufficient to reduce the number of calls on current accounts. These enhancements would only provide information on when the report was generated or what period it covers, but they would not change the fact that the report could be outdated by the time it reaches the collections manager. Therefore, these enhancements would not solve the problem of calling customers who have already paid their accounts.

The duration of a phone call in milliseconds is an example of:

A.
ordinal data.
A.
ordinal data.
Answers
B.
nominal data.
B.
nominal data.
Answers
C.
boolean data.
C.
boolean data.
Answers
D.
continuous data.
D.
continuous data.
Answers
Suggested answer: D

Explanation:

The correct answer is D. Continuous data.

Continuous data is a type of quantitative data that can take any value within a range and can be measured with infinite precision. Continuous data can be expressed as fractions, decimals, or percentages. Examples of continuous data are height, weight, temperature, time, speed, etc12

The duration of a phone call in milliseconds is an example of continuous data, because it can take any value within a range (from zero to infinity) and can be measured with infinite precision (up to milliseconds or even smaller units). The duration of a phone call in milliseconds can also be expressed as fractions, decimals, or percentages of a larger unit (such as seconds, minutes, or hours).

Ordinal data is not correct, because ordinal data is a type of qualitative or categorical data that can be ordered or ranked according to some criterion. Ordinal data can have a logical order, but the intervals between the values are not equal or meaningful. Examples of ordinal data are grades, ratings, ranks, etc12

Nominal data is not correct, because nominal data is a type of qualitative or categorical data that can be labeled or named without any order or ranking. Nominal data can have a finite number of categories or classes, but the categories have no intrinsic value or hierarchy. Examples of nominal data are gender, color, nationality, etc12 Boolean data is not correct, because boolean data is a type of binary data that can have only two possible values: true or false. Boolean data can be used to represent logical statements, conditions, or outcomes. Examples of boolean data are yes/no, on/off, 1/0, etc.

A site reliability team wants to monitor the stability of their website. so they can proactively diagnose issues when they occur Which of the following deliverables would best suit their needs?

A.
A self-serve dashboard of website performance that updates in real time
A.
A self-serve dashboard of website performance that updates in real time
Answers
B.
A weekly log report of site visits and user actions
B.
A weekly log report of site visits and user actions
Answers
C.
A portal that is refreshed daily and reports errors classified by type
C.
A portal that is refreshed daily and reports errors classified by type
Answers
D.
A daily summary email indicating website outages for the previous day
D.
A daily summary email indicating website outages for the previous day
Answers
Suggested answer: A

Explanation:

The best deliverable that would suit the site reliability team's needs is A) A self-serve dashboard of website performance that updates in real time.

A self-serve dashboard is a visual display of the most important information needed to achieve one or more objectives, consolidated and arranged on a single screen so the information can be monitored at a glance. A self-serve dashboard of website performance that updates in real time would allow the site reliability team to easily and quickly access the information they need about the stability of their website, such as uptime, response time, error rate, traffic volume, etc. A self-serve dashboard would also enable the team to proactively diagnose issues when they occur, by providing alerts, notifications, or drill-down options. A self-serve dashboard would also be more interactive and engaging than a report or an email.

A weekly log report of site visits and user actions would not be a good deliverable for the site reliability team's needs, because it would not provide timely or relevant information about the stability of their website. A weekly log report would be too infrequent and delayed to monitor and diagnose issues when they occur. A weekly log report would also focus on the behavior and actions of the users, rather than the performance and functionality of the website.

A portal that is refreshed daily and reports errors classified by type would not be a good deliverable for the site reliability team's needs, because it would not provide real-time or comprehensive information about the stability of their website. A portal that is refreshed daily would be too slow and outdated to monitor and diagnose issues when they occur. A portal that reports errors classified by type would be too narrow and limited to capture the full picture of the website performance.

A daily summary email indicating website outages for the previous day would not be a good deliverable for the site reliability team's needs, because it would not provide real-time or actionable information about the stability of their website. A daily summary email would be too late and retrospective to monitor and diagnose issues when they occur. A daily summary email indicating website outages would also be too passive and generic to help the team resolve or prevent issues in the future.

An analyst needs to join two tables of data together for analysis. All the names and cities in the first table should be joined with the corresponding ages in the second table, if applicable.

Which of the following is the correct join the analyst should complete. and how many total rows will be in one table?

A.
INNER JOIN, two rows
A.
INNER JOIN, two rows
Answers
B.
LEFT JOIN. four rows
B.
LEFT JOIN. four rows
Answers
C.
RIGHT JOIN. five rows
C.
RIGHT JOIN. five rows
Answers
D.
OUTER JOIN, seven rows
D.
OUTER JOIN, seven rows
Answers
Suggested answer: B

Explanation:

The correct join the analyst should complete is B. LEFT JOIN, four rows.

A LEFT JOIN is a type of SQL join that returns all the rows from the left table, and the matched rows from the right table. If there is no match, the right table will have null values. A LEFT JOIN is useful when we want to preserve the data from the left table, even if there is no corresponding data in the right table1

Using the example tables, a LEFT JOIN query would look like this:

SELECT t1.Name, t1.City, t2.Age FROM Table1 t1 LEFT JOIN Table2 t2 ON t1.Name = t2.Name; The result of this query would be:

Name City Age Jane Smith Detroit NULL John Smith Dallas 34 Candace Johnson Atlanta 45 Kyle Jacobs Chicago 39

As you can see, the query returns four rows, one for each name in Table1. The name John Smith appears twice in Table2, but only one of them is matched with the name in Table1. The name Jane Smith does not appear in Table2, so the age column has a null value for that row.

Which of the following best describes the law of large numbers?

A.
As a sample size decreases, its standard deviation gets closer to the average of the whole population.
A.
As a sample size decreases, its standard deviation gets closer to the average of the whole population.
Answers
B.
As a sample size grows, its mean gets closer to the average of the whole population
B.
As a sample size grows, its mean gets closer to the average of the whole population
Answers
C.
As a sample size decreases, its mean gets closer to the average of the whole population.
C.
As a sample size decreases, its mean gets closer to the average of the whole population.
Answers
D.
When a sample size doubles. the sample is indicative of the whole population.
D.
When a sample size doubles. the sample is indicative of the whole population.
Answers
Suggested answer: B

Explanation:

The best answer is B. As a sample size grows, its mean gets closer to the average of the whole population.

The law of large numbers, in probability and statistics, states that as a sample size grows, its mean gets closer to the average of the whole population. This is due to the sample being more representative of the population as it increases in size. The law of large numbers guarantees stable long-term results for the averages of some random events1

A) As a sample size decreases, its standard deviation gets closer to the average of the whole population is not correct, because it confuses the concepts of standard deviation and mean. Standard deviation is a measure of how much the values in a data set vary from the mean, not how close the mean is to the population average. Also, as a sample size decreases, its standard deviation tends to increase, not decrease, because the sample becomes less representative of the population.

C) As a sample size decreases, its mean gets closer to the average of the whole population is not correct, because it contradicts the law of large numbers. As a sample size decreases, its mean tends to deviate from the average of the whole population, because the sample becomes less representative of the population.

D) When a sample size doubles, the sample is indicative of the whole population is not correct, because it does not specify how close the sample mean is to the population average. Doubling the sample size does not necessarily make the sample indicative of the whole population, unless the sample size is large enough to begin with. The law of large numbers does not state a specific number or proportion of samples that are indicative of the whole population, but rather describes how the sample mean approaches the population average as the sample size increases indefinitely.

A data analyst needs to perform a full outer join of a customer's orders using the tables below:

Which of the following is the mean of the order quantity?

A.
73.5
A.
73.5
Answers
B.
76.5
B.
76.5
Answers
C.
78.8
C.
78.8
Answers
D.
81.5
D.
81.5
Answers
Suggested answer: D

Explanation:

The correct answer is D. OUTER JOIN, seven rows.

An OUTER JOIN is a type of SQL join that returns all the rows from both tables, regardless of whether there is a match or not. If there is no match, the missing side will have null values. An OUTER JOIN can be either a LEFT JOIN, a RIGHT JOIN, or a FULL JOIN, depending on which table's rows are preserved1 Using the example tables, a FULL OUTER JOIN query would look like this:

SELECT Cust_id, Order_id, Order_qty FROM Sales_table FULL OUTER JOIN Order_table ON

Sales_table.Order_id = Order_table.Order_id;

The result of this query would be:

Cust_id | Order_id | Order_qty --------±---------±--------- 1 | 1 | 100 2 | 2 | 50 3 | 3 | 25 4 | 4 | 75 NULL | 5 | 10 NULL | 6 | 20 NULL | 7 | 15

As you can see, the query returns seven rows, one for each order in either table. The orders that are not in the Sales_table have null values for the Cust_id column.

To find the mean of the order quantity, we need to sum up the order quantities and divide by the number of rows. In this case, the mean is (100 + 50 + 25 + 75 + 10 + 20 + 15) / 7 = 42.14. Rounding to one decimal place, we get 42.1 as the mean of the order quantity.

An analyst is currently working on a ticket for revamping a company-wide dashboard that has been in use for five years. Which of the following should be the first step in the development process?

A.
Talk to the group that made the request to determine the desired goal.
A.
Talk to the group that made the request to determine the desired goal.
Answers
B.
Make changes to a frequently used report that is already in production.
B.
Make changes to a frequently used report that is already in production.
Answers
C.
Build an additional dashboard with fewer views that are tailored toward each specific team.
C.
Build an additional dashboard with fewer views that are tailored toward each specific team.
Answers
D.
Develop a more streanMined dashboard to roll out by the next delivery date.
D.
Develop a more streanMined dashboard to roll out by the next delivery date.
Answers
Suggested answer: A

Explanation:

The first step in the development process of revamping a company-wide dashboard should be to talk to the group that made the request to determine the desired goal. This would help to understand the needs, expectations, and preferences of the stakeholders, as well as the scope, purpose, and objectives of the project. Talking to the group that made the request would also help to establish a clear communication channel, build rapport and trust, and solicit feedback and suggestions.

A research analyst collects ten data points from 1.000 specimens. The analyst will not need any additional data to complete the analysis and will not need to retrieve information by specifier. Which of the following is the best data structure for the analyst to use?

A.
NoSQL
A.
NoSQL
Answers
B.
Flat file
B.
Flat file
Answers
C.
JSON
C.
JSON
Answers
D.
Relational database
D.
Relational database
Answers
Suggested answer: B

Explanation:

A flat file is a type of data structure that stores data in a plain text format, such as CSV, TSV, or TXT. A flat file consists of one or more records, each containing one or more fields, separated by a delimiter, such as a comma, tab, or space. A flat file does not have any hierarchical or relational structure, and does not support any complex queries or operations1.

A flat file may be the best data structure for the analyst to use in this scenario, because:

The analyst collects ten data points from 1,000 specimens, which means the data is relatively small and simple, and can be easily stored and processed in a flat file.

The analyst will not need any additional data to complete the analysis, which means the data is static and does not require any updates or modifications.

The analyst will not need to retrieve information by specifier, which means the data does not require any indexing or searching by key or value.

Which of the following best describes the process of examining data for statistics and information about the data?

A.
Cleansing
A.
Cleansing
Answers
B.
search
B.
search
Answers
C.
Profiling
C.
Profiling
Answers
D.
Governance
D.
Governance
Answers
Suggested answer: C

Explanation:

Data profiling is the process of examining data for statistics and information about the data, such as the structure, format, quality, and content of the dat a. Data profiling can help to understand the characteristics, patterns, relationships, and anomalies of the data, as well as to identify and resolve any errors, inconsistencies, or missing values in the data. Data profiling can be done using various tools and methods, such as spreadsheets, databases, or programming languages12.

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