A PREDICTION MODEL FOR USER S SHARE ANALYSIS IN DUAL- SIM ENVIRONMENT

Transcription

1 GSJ: Computer Sciece ad Telecommuicatios 03 No.3(39) ISSN 5-3 A PRDICTION MODL FOR USR S SHAR ANALYSIS IN DUAL- SIM NVIRONMNT Thakur Sajay, Jai Parag Orietal Uiversity, Idore, Idia sajaymca00@yahoo.com Abstract As soo as the dual-sim hadsets are gettig popularity i the coutry a call-bycall competitio occurs amog the operators or mobile service providers. Due to call cogestio, users must ofte make repeated call attempt at Sim util gettig the coectivity. Durig the repeated callig process the user will be able to chage his choice of Sim o call-by-call basis. I this paper a Markov chai proposed as a predictio model for aalysis the user s behaviour i the set up of dual Sim mobile eviromet. This model use to predict the effect of cogestio o iitial traffic share betwee the Sims. Keywords: Markov Chai Model, Trasitio Probability Matrix, Mobile Service Providers (Operators), User s Behaviour I. Itroductio A survey coducted by Nielse reveals that 7 millio or approximately 8 per cet of more tha 900 millio mobile users i Idia use multiple Sim cards. The survey says cities with populatio betwee 5-0 lakh have the highest desity of multiple Sim users, which is about percet. About percet of multiple Sim users are based out of tows with 40-lakh populatio. Fig.. Multi-Sim users accordig Nielse Survey Oly 9 percet of users belog to rural areas, says the survey. I Nielse survey the youth are the highest multi-sim users, as much as 45 percet betwee the age group of 8-5 years old. Most of them are studets, workig professioals ad ewly employed. A multi-sim user prefers differet operators ad prepaid coectio. Iterestigly, 6 percet of multi-sim users are owers of dual-sim phoes. A. Key reasos for choosig Multi-Sim: The 3% or 6,00 respodets said that they use more tha oe Sim card to get access to better deals ad offers. Additioal 7% or 3,400 respodets said that they carried multiple Sims to avail the best tariff optios available. Other reasos why the respodets used multiple Sim cards varied from cotiuous etwork coectivity, UGs ad segregatio of work ad private calls. While these reasos were o a persoal level, it is iterestig to ote that 6% used multiple Sim cards just 06

2 GSJ: Computer Sciece ad Telecommuicatios 03 No.3(39) ISSN 5-3 because it was give as a add-o by their service provider. Additioally 5% said that their secodary Sim card was budled alog with the purchase of their hadset. The two categories together reveal that,00 respodets use multiple Sim cards just because they ve bee give oe. B. Mobile Statio Mobile statio (MS) commuicates the iformatio with user. The MS has two elemets. The first elemet is mobile equipmet (M), which is a piece of hardware that the customer purchases from the equipmet maufacture or their dealers. The secod elemet of MS i the GSM is the subscriber idetity module (Sim) that is a smart card issued at the subscriptio time idetifyig the specificatios of a user such as address ad type of service. Implemetig a Sim is a fairly simple cocept, it has a sigificat impact o the way that user trasacts with the service provider. MS Sim user M Fig.. Mobile Statio Due to cogestio i packet flow i etwork, users have to make repeated call attempts before gettig their call coected by a Sim. Due to other techical problems, the etwork of a mobile service provider fails to provide coectivity eve after a large umber of efforts ad users thik of to chage the Sim of service provider to get a early coectivity for commuicatio. Cyberetic traffic model i the IXPs/SP eviromet with e-services is preseted by [3], which simulate IXPs/SPs market competitio behaviour. I this paper, we make a simple traffic predictio model for aalyze the user s behaviour i dual- Sim eviromet. Cotributios of [], [], [4], [5] are used as helpig tools to desig ad perform the model based study. II. User s Behavior Model We start the simulatio with dual Sim. We cosider followig hypotheses for the behavior of user, while sharig the call betwee the two Sim. The user has a dual Sim mobile phoe, cotaiig Sims, S ad S of two differet mobile service provider or operators. A user iitially chooses oe of the two Sim with probability p ad (-p) for S ad S respectively (0 p ). The p is affected by advertisig, marketig, quality-of-service ad past preferece (or attractiveess). X (- After each failed call attempt, the user has two choices: he ca abado with probability p, switch over to other Sim for a ew call. Switchig amog S ad S is o dail-by-dail basis depedig just o the latest attempt. Durig the repeated calls, the cogestio probability offered by S is C ad of S is C. The cogestio implies situatio whe call attempt process fails to coect a Sim. Uder above hypotheses the user s behavior ad attitude could be modeled by a four-state discrete-time Markov chai {X (), 0} such that X () stads for the state of radom variable X at th attempt made by a user over state space {S, S, Z, }, where State S : Sim correspodig to first service provider State S :Sim correspodig to secod service provider 07

3 GSJ: Computer Sciece ad Telecommuicatios 03 No.3(39) ISSN 5-3 State Z: Success (i coectivity) State : xit from call coectivity attempt process. Z -C C (-p ) -C User S S C p C (-p ) C p Fig.3. Model of user s behavior i the dual Sim case The trasitio probabilities are idicated o the arcs coectio the circles represetig the chai states. The time is represeted by the umber of attempts. P[ X () = S i ] (i =,) is the probability that the ( + ) th call attempt is placed through the Sim S i. The Fig. 3 explais the trasitio i model ad Fig. 4 is a trasitio probability matrix of the model. X () S S Z S 0 C (-p ) -C C p X (- S C (-p ) 0 -C C p Z Fig.4. Oe step Trasitio Probabilities Matrix III. th Step State Probabilities ( ) [ X S ] = p ( C C ) ( p P = ), eve () ( ) [ X = S ] = ( p) C ( CC ) ( p P ), odd (3) ( ) [ X S ] = p) ( C C ) ( p P = ), eve (4) ( ( ) [ X = S ] = pc ( C C ) ( p 08 P ), odd (5)

4 GSJ: Computer Sciece ad Telecommuicatios 03 No.3(39) ISSN 5-3 IV. The Quality of Service xperiece by User The pricipal goal of user is to complete the call. User experieces cogestio probability that is a first quality of service parameter. I our model a user categorized as: a) Dedicated User (DU) Who sticks with the Sim [S i (i =, ) oly)], it has chose for its first attempt otherwise, prefers to abado, but does ot attempt for other competitive. b) Udedicated User (UDU) Who toggles betwee two Sim (S i ad S j, i j =, ) till he either completes his call or exits. A. Average Cogestio Probability for Users If dedicated user chose the Sim S the he always experieces the same cogestio probability C otherwise C. Averagig over these two choices gives us the average cogestio probability B d for the dedicated user: B d = pc ( C. (6) + p) Istead, at the th attempt udedicated user experieces a varyig cogestio probability it is B P[ X = S ] C + P[ X ( ) ( ) ( ) ud = ( ) ( ) P[ X = S] + P[ X = S ] C = S ]. (7) Sice the state probabilities for the two states S ad S at the th attempt deped o whether is eve or odd.we obtai two expressio for cogestio probability of the udedicated user by usig expressio ()-(5) i exp. (7): ( ) CC B =, whe eve (8) ud pc + (- p)c B ( ) ud = pc + ( p) C, whe odd (9) So, B d = B ud, whe eve, B du < Bd or B du > Bd, whe odd. CC C p <, C < C (0) C - C CC C p >, C > C. () C - C Fig.4 ad Fig.5 reveals that the udedicated user icreases the iitial share of S whe the S cogestio probability is 0.0 ad 0. respectively. 09

5 GSJ: Computer Sciece ad Telecommuicatios 03 No.3(39) ISSN Udedicated users iitial share Dedicated users cogestio probability from Sim Fig.4 iitial share whe C = Dedicated users itial share Udedicated users cogestio probability from Sim Fig.5 iitial share whe C = 0.. The iitial market group p of a Sim highly depeds o etwork cogestio probabilities C ad C. The udedicated user always have to keep larger iitial traffic share tha dedicated user irrespective of whatever may the values of C.The proportio of udedicated user is lesser tha the dedicated user whe oppoet's cogestio probability is small, but icreases gradually as the C icreases. V. Coclusio The proposed Predictio model for user's behavior explais the iitial traffic sharig patter i dual-sim mobile. The competitor's cogestio probability has a strog impact over improvig 0

6 GSJ: Computer Sciece ad Telecommuicatios 03 No.3(39) ISSN 5-3 proportio of dedicated users of S.The smaller service provider are more popular amog the multi- Sim users. Ackowledgmet The author is grateful to Prof. Shukla of the Sagar Cetral Uiversity, Sagar. He offered very useful advices. Refereces. maual, Perze, Stochastic Processes, Holde -Day, Ic., Sa Fracisco, ad Califoria,99. J. Medhi. Stochastic Processes, Wiley aster Limited (Fourth reprit), New Delhi, J.K. Chiag ad K. Huag, A Simulatio ad Predictio Model for Cyber Traffic Sharig ad Market Competitio, published i 8 th Iteratioal Symposium o advaced Itelliget system Sep 5-8, 007,Korea.. 4. J.J. Gordo,K. Murti, A. Rayes, Overview of Iteret traffic issues o the PSTN, 5 th Iteratioal Teletraffic Cogress, Washigto, -7 Jue 997,pp M. Naldi, The Iteret s growth problems, Telecommuicatios 3() pp 55-59, Yeia, C. ad Lygeres, J. Stabilizatio of A Class of Stochastic Differetial quatios with Markovia Switchig, System Ad Cotrol Letters, 9, pp , Article received: