TheMainstreamSeer

Social network analysis  (SNA) is the methodical analysis of  social networks .  Social network analysis views  social relationships  in terms of  network theory , consisting of  nodes  (representing individual actors within the network) and  ties  (which represent relationships between the individuals ) .   These networks are often depicted in a social  network diagram , where nodes are represented as points and ties are represented as lines. Example of a social network diagram Relationships in a network can either be directional or nondirectional .  In a directional relationship, one person is the initiator (or source of the relationship) while the other is the receiver (or destination of the relationship).  For example, in the diagram above, node 1269 is the source while node 3777 is the destination.  Relationships can also be described as dichotomous or valued .  A dichotomous relationship i...

Direct Mail Campaigns (and their online equivalents) continue to be a popular method to promote a company's offer to potential customers.  All of us have received letters from retail stores, financial institutions and other companies with special offers that prompt us to take speedy action to avail of a discount, a bonus or similar attractive proposition.  In most cases, I tend to discard these letters without opening them and in rare cases I open them before deciding that they don't apply to me.  My behavior is not unique; typical response rates for direct mail campaigns hover around 2% - 3% which means most folks who receive these direct mailers tend to discard them.  For companies, this is obviously not good news.  Each mailer costs them money (printing and postage) so it is in their best interest not to send out a direct mail to someone that is not likely to respond positively to a campaign. So for example, a company sends out 1,000,000 direct mailers ...

Text analytics, sometimes alternately referred to as text data mining or  text mining , refers to the process of deriving high-quality information from text .  High-quality information is typically derived through the devising of patterns and trends through means such as statistical pattern learning .  Text mining usually involves the process of structuring the input text , deriving patterns within the structured data , and finally evaluation and interpretation of the output.   Typical text mining tasks include text categorization , text clustering , concept / entity extraction , production of granular taxonomies,  sentiment analysis , document summarization  and entity relation modeling (i.e., learning relations between named entities ).   The overarching goal is, essentially, to turn text into data for analysis via application of natural language processing (NLP) and analytical methods.   A typical application is to scan a set of documents wr...

In today's post, we explore the use of decision trees in evidence based medicine.   In 1996  David Sackett  wrote that "Evidence-based medicine is the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients" [Source: Wikipedia]. For our analysis, we start with a data set which contains data about a number of patients all of whom suffered from the same illness.  Each of these patients responded well to one of five medications.  We will use a decision tree to understand what factors in each patients history led to them responding well to one specific medication over the others.  We will then use our findings to generate a set of evidence based rules or policies that can be followed by doctors to treat this illness in future patients.  As part of our analysis, we will also explore how to interpret decision trees. Let us first look at our data set: As can be seen, the da...

In today's post, we dive into understanding Association Rules for Market Basket Analysis and discuss three numeric measures that should be considered before deciding to act on / make a business decision based on associations that have been observed in the data: (1) Support (2) Confidence and (3) Lift. Association rules are typically written in the format: Left hand side Implies Right hand side The left hand side is referred to as the Antecedent and the right hand side is the Consequent.  The Antecedent means a thing that logically precedes another while a Consequent means a thing that follows as a result.  For example, in the association rule: {Butter, Eggs} Implies {Bread} Butter and eggs are the Antecedent while Bread is the Consequent.  What this rule means that if you were to pick a shopping cart at random and find butter and eggs in there, there is a chance that you are also likely to find bread. The numeric measures mentioned above (Support, Confidenc...