Sales Forecast - Exogenous vs Endogenous Variables

Sometimes jargon occupies too much of concepts, Being able to explain it in business terms is key to being able to relate to it. 

Now we have data drift, and model drift. 13 years ago when we implemented forecast when the actual and prediction varied we ask the store manager 

• Reason for it
• Does actual data make sense for future training or use forecasted data

Terms Exogenous / Endogenous can be put in more business-friendly Terms :)

Exogenous - External cause

1. Market Trends: This refers to the overall direction in which the market that the product or service is operating in is headed. It includes factors such as consumer behavior, buying trends, or preferences which can affect the sales forecast significantly.

2. Economic Conditions: This includes factors like inflation rates, unemployment rates, gross domestic product (GDP), etc. These conditions can influence consumer spending and thus directly affect the sales forecast.

3. Competition: The actions (like pricing strategies, marketing campaigns, product launches) of competitors in the market can also significantly impact the sales of a product or service. Hence, this is an important exogenous variable in sales forecast.

Endogenous - Internal cause

1. Past Sales Data: The historical sales performance is a key factor in predicting future sales. Based on historical data, businesses can form patterns and trends that help in forecasting future sales.

2. Pricing: The price of a product or service plays a crucial role in determining its demand. Changes in price, due to factors like discounts, offers, etc., can significantly influence sales.

3. Advertising and Promotions: The level of advertising and promotional activities can impact the demand of a product or service. Businesses can increase sales by intensifying their marketing efforts. Therefore, the effectiveness of advertising and promotional activities is directly related to the sales forecast.

Keep Exploring!!!

One Liners, Concepts, Slowly Changing Dimensions

SCD Summary

Sometimes one link is good enough to summarize 

• Type 1 - Overwrite previous value
• Type 2 - Add new row, Deactive old record, activate new one
• Type 3 - Add new attribute - Activation Data / Effective Date
• Type 4 - Add History Table

Docker - Docker is a tool designed to make it easier to create, deploy, and run applications by using containers

Kubernetes - Kubernetes is a portable, extensible, open-source platform for managing containerized workloads and services

Docker vs VM

• In Docker, the containers running share the host OS kernel
• A Virtual Machine, on the other hand, is not based on container technology. They are made up of user space plus kernel space of an operating system

More Reads

Kubernetes cheatsheet

Keep Simplifying Concepts!!!

Concepts - Heuristics vs ML, Deterministic vs. stochastic models

Heuristics vs ML

• A heuristic is a way to find the solution to some problem without exhaustively trying all possible solutions, or without knowing the answer ahead of time.
• A heuristic is a strategy for finding a solution to a problem faster or approximating a solution for it
• The term heuristic is used for algorithms that find solutions among all possible ones,but they do not guarantee that the best will be found

Ref - Link

• Heuristic is any approach to problem-solving, learning, or discovery that employs a practical method not guaranteed to be optimal or perfect, but sufficient for the immediate goals.

Ref - Link

Machine Learning is different, in that instead of teaching the computer the technique that you found for solving the problem 

Sampling-based techniques

• Do not require first or second derivative
• Exhaustive search
• Simulated annealing
• Genetic Algos

Gradient-based techniques

• Branch and bound

Algorithms for Decision Making: Optimization, Heuristics and Machine Learning

Deterministic vs. stochastic models

• In deterministic models, the output of the model is fully determined by the parameter values and the initial conditions.
• Stochastic models possess some inherent randomness. The same set of parameter values and initial conditions will lead to an ensemble of different outputs
• Demographic stochasticity describes the randomness that results from the inherently discrete nature of individuals
• In deterministic algorithm, for a given particular input, the computer will always produce the same output going through the same states
• non-deterministic algorithm, for the same input, the compiler may produce different output in different runs

Ref Link

P, NP, NP-Hard & NP-complete problems

It takes time to connect all the dots and plot the big picture. Keep Plotting!!!

Jargons - Docker - Kubernetes

I found this katacoda course practical useful for this basics

• Containers - Linux Process
• Docker - Type of container
• Kubernetics - For orchestrating containers
• Kuberflow - Deploy Machine Learning workloads using Kubeflow on Kubernetics

Kubernetes vs docker

• A fundamental difference between Kubernetes and Docker is that Kubernetes is meant to run across a cluster while Docker runs on a single node. 
• Kubernetes is more extensive than Docker Swarm and is meant to coordinate clusters of nodes at scale in production in an efficient manner

Ref - Link 

Ref - Link

The container lifecycle managed by docker includes :

𝗨𝘀𝗲𝗿 --> 𝗱𝗼𝗰𝗸𝗲𝗿 𝗰𝗺𝗱 --> 𝗱𝗼𝗰𝗸𝗲𝗿 𝗱𝗮𝗲𝗺𝗼𝗻 --> 𝗿𝘂𝗻𝗰 --> 𝗖𝗼𝗻𝘁𝗮𝗶𝗻𝗲𝗿𝘀

Let's see the container lifecycle in k8s using docker-engine:

𝗞𝘂𝗯𝗲𝗹𝗲𝘁 --> 𝗗𝗼𝗰𝗸𝗲𝗿𝘀𝗵𝗶𝗺 --> 𝗗𝗼𝗰𝗸𝗲𝗿 --> 𝗖𝗼𝗻𝘁𝗮𝗶𝗻𝗲𝗿𝗱 --> 𝗖𝗼𝗻𝘁𝗮𝗶𝗻𝗲𝗿𝘀

The new Kubernetes containers lifecycle architecture includes :

𝗞𝘂𝗯𝗲𝗹𝗲𝘁 --> 𝗰𝗼𝗻𝘁𝗮𝗶𝗻𝗲𝗿𝗱 + 𝗖𝗥𝗜 𝗣𝗹𝘂𝗴𝗶𝗻𝘀 --> 𝗖𝗼𝗻𝘁𝗮𝗶𝗻𝗲𝗿𝘀

Linux containers in 500 lines of code

why containers? pic.twitter.com/ykSaiWqvTN

— 🔎Julia Evans🔍 (@b0rk) February 4, 2020

Containers Basics

Docker Questions & Answers

• A new way to create things like virtual machines
• Custom images based on other images, Lightweight images
• Create things in a contained environment

Deployment Tips

• Expose only required ports
• Plan for App restart on crash

Docker Perspectives

• With Docker, resources shared between containers
• Infra that surrounds lxc
• Resolve works on my machine problem, ease deployments, shuffle between systems

Happy Learning!!!