Category: Discrete Math

Set Theory as a Framework for Relational Databases A set can be a collection of

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Set Theory as a Framework for Relational Databases
A set can be a collection of

Set Theory as a Framework for Relational Databases
A set can be a collection of any type of object, ranging from people to places to things. Basic set theory includes the study of subsets, proper subsets, finite and infinite sets, and the logical operations on them. Set theory plays a foundational role in mathematical processes and ideas and also has connections to computer engineering, programming, and databases.
The relational database model, originally invented by computer scientist Edgar F. Codd in 1969, is based on ideas from set theory. A simple database is a collection of records stored in tables. A relational database also includes relationships stored across multiple tables. One can run queries on the relational database to request specific information with set theory operators, such as union and intersection.
Post 1: Initial Response
Imagine you are responsible for your organization’s analytic tasks, and you are currently brainstorming how to query a relational database of marketing information for the organization. You want to test your understanding of how you might relate the database tables with the use of set theory, and particularly subsets. To carry out your test, complete each of the following:
To define two sets, set A and set B, first conduct an online browsing trial, in which you spend 10–20 minutes looking at different websites, such as for national news, social media, sports, hobbies, recipes, etc. Let set A represent exactly three distinct company names from any online advertisements you saw during your browsing trial. Let set B represent at least three distinct company names for any online retailers you have purchased from in the past year.
To prepare to use your algorithm, answer the following questions:How many elements are in set A? This is what you will set as m = ___.
How many elements are in set B? This is what you will set as n = ___.
What are your first and last elements of A? Show these as a[1] = ____ and a[m] = ___.*
What are your first and last elements of B? Show these as b[1] = ____ and b[n] = ___.*
Using your sets A and B along with what you just outlined to prepare, determine an algorithm that you can use to see whether A ⊆ B. You can make your own or find one somewhere else.
State the algorithm that you would use to compare these sets. If you are using an algorithm that you did not write, cite or describe where you found it.
Based on your algorithm, did you find that A ⊆ B or that A ⊈ B? Explain. If A ⊈ B, how are they related (e.g., disjoint, intersecting)?
View Unit 6 Discussion Post 1 example.
Post 2: Reply to a Classmate
Now you want to try out the algorithm on another person’s data to further test your understanding and bolster your confidence about assessing relations computationally as you approach this relational database project.
Review a classmate’s post and consider their set B. Address the following items completely.
Using your set A and their set B, use the algorithm they described to determine whether A ⊆ B or A ⊈ B? Explain how you know this. If A ⊈ B, how are they related (e.g., disjoint, intersecting)?
How might the understanding you have gained from your Post 1 and Post 2 tests be useful if you were responsible for querying a relational database?
View Unit 6 Discussion Post 2 example.
Post 3: Reply to Another Classmate
After conducting this computational practice, you have begun to develop some technical insight into how you might investigate and seek information on the marketing habits of clients by querying a relational database. However, you know your fellow staff members are not interested in this technical insight. So, for your general meeting, you plan to present a visual synopsis of some ideas considered in the planning stages of this project.
Review another classmate’s post and consider their sets A and B. Address the following items completely.
Create a Venn diagram that models all of the elements in your classmate’s sets A and B. Carefully place elements appropriately in the intersecting versus non-intersecting areas representing sets A and B, respectively. You may use the software of your choice for the Venn diagram (e.g., creatly.com, cosketch.com, Microsoft® Word®, or PowerPoint®). Copy and paste the image or screenshot of your Venn diagram into your post. (You may also use an attached file if needed.)
Draft some talking points in anticipation of addressing the following questions during your presentation:How do these two sets relate in the example illustrated by the Venn diagram?
How have the concepts of sets and set operations been utilized in your analytic tasks?
How might table relationships be modeled from the ideas of set theory?
View Unit 6 Discussion Post 3 example.

Modeling Population Growth You can generally model population growth as either l

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Modeling Population Growth
You can generally model population growth as either l

Modeling Population Growth
You can generally model population growth as either linear by an arithmetic sequence, or exponential by a geometric sequence. These can be defined by one of the general forms:
Arithmetic Sequence
an = a0 + d∙n where,
d is the common difference (change per year for population increase or decrease)
n is a natural number indicating the years since the initial period
a0 is the population in the initial period
Geometric Sequence
an = a0∙rn where,
r is the common ratio (multiple for population increase or decrease per year)
n is a natural number indicating the years since the initial period
a0 is the population in the initial period
Post 1: Initial Response
Suppose you are working as an IT consultant and are known to have keen mathematical skills in addressing real-world situations. You have recently been contacted by a city council to present a plan for a population growth/decline initiative. The council has in recent years experienced considerably unexpected changes in population due to obsolete models and no use of technology. This has left them scrambling to find remedies for the city (e.g., new roads if the population is growing, repurpose vacant lots if the population is declining).
You will spearhead this initiative, and you are charged with planning a mathematical model for future use and prioritizing the city council’s use of technology. Your goal is to apply your knowledge of sequences and create an appropriate mathematical model for the city’s population growth/decline. You will also share the technological tools that can be used to employ this model well into the future in the form of a computer algorithm.
In planning for your goal, you will want to briefly describe the city population growth/decline scenario and identify what factors might contribute to the growth/decline. This initial stage of planning is critical in creating an accurate mathematical model. You also want to present how your model can be codified as a computer algorithm so that the council’s staff can use it in the future.
Draft a detailed response to the council to demonstrate what you propose for more effectively modeling and preparing for population changes in the future.
View Unit 5 Discussion Post 1 example.
Include all of the following in your response.
Provide a narrative introduction to the planning initiative, where you:Briefly describe the situation in which population growth/decline is being considered and modeled
State whether you project the population growth/decline to be linear or geometric in nature
Identify at least three factors you believe might be contributing to the unexpected population growth/decline (i.e., birth, disease, innovations, trends, migration)
Discuss and prioritize which of these factors you believe has possibly had the greatest impact on the population growth/decline
Reflect on how that factor may relate to one of the inputs in the model
Present your proposed mathematical model for how the council estimates the future population each year, using either an arithmetic or a geometric sequence. Clearly state the following:Initial population size, a0
Your change variable, d or r
The general equation for your model with these two inputs substituted into the formula
Write an algorithm that will take as input the number of years (n) since the initial period, and that will output the population size for each year from now until the nth year. Your algorithm must use an iterative operation (such as a while or for-next loop).
Post 2: Reply to a Classmate
Review a classmate’s population model scenario, equation, and algorithm. If no other classmate has yet responded, review their model for accuracy by providing an input value for n ≥ 5 and perform a trace of the algorithm.
View Unit 5 Discussion Post 2 example.
Address the following:
Write out the outputs in a trace table.
Select two future population estimates (two output values of an) and discuss whether the output produced is appropriate for the scenario. What limitations, or problems, may there be in using this model to estimate the population indefinitely?
Based on your assessment of the output and potential limitations of the model, suggest a change to the general formula or algorithm for their sequence to represent a potentially better long-term model for the scenario. (You may consider the factors that were described in the initial planning phase or other biological limitations on growth/decline of populations.)
Post 3: Reply to Another Classmate
Review a different classmate’s population model scenario, equation, and algorithm. You will improve their model to account for a potential event that could affect the population growth/decline.
Modify your classmate’s population model by adjusting their algorithm with a conditional statement (if-then or if-then-else) for some event that leads the population to slow its growth or decline (or reverse between growth versus decline) at a specific population size (i.e., you choose a specific value of an).
View Unit 5 Discussion Post 3 example.
Address the following:
Copy their original algorithm into your post and insert a conditional operation into an appropriate place to account for this change in the model. (You will need to incorporate a second formula with an updated value for d or r, for use when your conditional operation begins taking effect.)
Select an input value for n, large enough so that it will trigger your conditional statement to calculate some population estimates using your revised model, or second formula.
Perform a trace of the algorithm using this value of n and write out the outputs in a trace table.
Describe and explain the results, commenting specifically in your role as a consultant on how you believe this is now a good long-term modeling algorithm for the scenario.

You will have to complete work using Codio on google chrome. Please be computer

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You will have to complete work using Codio on google chrome. Please be computer

You will have to complete work using Codio on google chrome. Please be computer literate you will have to use an application called Codio. I will provide my log in. There is 8 problems I will send the rest once bid is accepted its not allowing me to add all.