Context-Awareness Recommender System

Context-Awareness Recommender System

Personalized recommendation systems have advanced with context-aware recommender systems, which use contextual data to improve the relevancy and accuracy of recommendations. Context-aware recommender systems take into account extra situational elements that might greatly impact user behavior and preferences, in contrast to standard recommender systems that largely focus on user preferences and item qualities.

Contextual data, including time, location, weather, and social environment, is included in the recommendation process as the fundamental idea of context-aware recommender systems. Consider how a user may select a different kind of restaurant based on the weather or enjoy a different kind of music depending on the time of day. The system's ability to comprehend and integrate these contextual aspects enables it to generate suggestions that are more precise and sophisticated.

Working of Context-Awareness Recommender System

The unique feature of context-aware recommender systems is their incorporation of situational information into the recommendation process, which improves the relevance and accuracy of suggestions. Context modeling, or finding and gathering pertinent contextual data that influences user preferences, is the cornerstone of a context-aware recommender system. Context can be implicitly deduced via sensors and behavior patterns, or directly given by the user by entering the current place or time. For example, GPS information may be obtained from mobile devices, and activity timestamps might reveal preferences at certain times of day.

One essential element is user profiling, in which users' profiles are generated depending on how they engage with the products, usually by means of explicit ratings or implicit behaviors like clicks, views, or purchases. In essence, a user's profile is an amalgam of these things' traits enhanced by contextual data. For instance, a user's preferred music may change based on the time of day or what they're doing-for instance, whether they're working out or just resting.

Item profiling is applied to every item in the catalog, taking into account its characteristics and any contextual significance. A movie may be characterized, for example, by its genre, director, cast, and keywords. It can also take into account the usual situations in which people like to watch particular kinds of movies. The similarity between items is computed by the system using a variety of algorithms, including Euclidean distance, cosine similarity, and more sophisticated ones like word embeddings and TF-IDF. Contextual variables provide depth to similarity calculations by allowing objects to be identified that are relevant to the user's present situation in addition to sharing similar features.

Lastly, recommendation generation produces recommendations that are most in line with the user's profile and present context by utilizing similarity scores and contextual relevance. An e-commerce website, for instance, may provide product recommendations based on the user's past browsing activity, time of day, and present location. Through the incorporation of contextual knowledge into the recommendation process, these systems improve user experience and engagement in a range of applications, including smart homes and e-commerce.

Importing Libraries

Reading the Dataset

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Context-Awareness Recommender System
Context-Awareness Recommender System

Missing Value

This stage involves locating and eliminating rows that have coordinates (longitude and latitude) that have an NA or null value.

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Context-Awareness Recommender System

Pre-Filtering

We attempt to eliminate noisy coordinates and identify possible sites that might be regarded as tourism destinations using DBSCAN clustering.

We must ascertain the DBSCAN clustering's optimal performance parameters. Thus, we get the right values for eps and min_pts/min_samples using a trial-and-error method.

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Context-Awareness Recommender System
Context-Awareness Recommender System

We choose eps = 120 and min_sample = 10 for the data.

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Context-Awareness Recommender System

Cluster Analysis

All clusters and their centroids are shown in two geographical and non-geographical perspectives in the plots below. DBSCAN produces a series of picture clusters, denoted by ?={?1,?2,...,??}. Every member in this group is a tourist destination that fits the definition of ??={???,???}. The collection of all images collected at location ??, where the centroid geographic coordinate is ???, is called ???.

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Context-Awareness Recommender System
Context-Awareness Recommender System

Output:

Context-Awareness Recommender System
Context-Awareness Recommender System
Context-Awareness Recommender System
Context-Awareness Recommender System

Location Profiling

In this stage, we extract the attributes associated with each tourist destination from the preceding step. Information such as the geographic location, the user's ID, the time spent visiting, and the context of the visit are all contained in each location that the clustering has found. It's crucial to understand that when a user visits a venue, they may take many pictures of the area. Consequently, we may assume that two images taken by the same person at the same place are from the same location if the time interval between their timestamps is shorter than the visit duration criterion (threshold). If not, the visit time with new contexts may be determined by taking the median of the timestamps.

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Context-Awareness Recommender System

Recommendation Model

Contextual factors are included in the POI dataset that is loaded. The location profile dataframe, or LPD, is assumed for this dataset. Only visitors who have visited at least four different destinations were chosen to be included in the recommendation model. Next, the data is divided into test and training sets.

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Context-Awareness Recommender System

In order to generate a rating matrix, we must ascertain how frequently each user has visited certain locations. The min-max normalization technique also normalizes ratings.

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Context-Awareness Recommender System

Output:

Context-Awareness Recommender System

Now let's create the user-user similarity matrix.

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Context-Awareness Recommender System

The matrix below shows the number of visits from venues in various contexts.

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Context-Awareness Recommender System

Output:

Context-Awareness Recommender System

Final Recommendation

By using user-based collaborative filtering, it is possible to forecast destinations that have not been evaluated by users based on user similarities and tourist location profiles. Predicted ratings are modified based on contextual data using a post-filtering technique.

In order to forecast the first ratings, we employ user-based collaborative filtering.



Let's look at the outcome of a rating prediction for a user who visited several spots in London City as an example. A list of suggested venues would include the top ten places with the highest ratings.

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Context-Awareness Recommender System

Output:

Context-Awareness Recommender System

Evaluation

In the final step, we evaluate the proposed method based on common evaluation metrics in recommendation systems, MAP and RMSE.


Output:

Context-Awareness Recommender System

The system is able to understand various contextual conditions such as location, time of visit, day/night, season, and weather conditions of the venue at the time of visit.