Dynamics of Duopoly Models with Undecided Clients under Decentralized Affine Feedback Advertising Policies

<div>Phase plane of the market shares of firms <svg height="9.14241pt" id="M379" style="vertical-align:-3.1815pt" version="1.1" viewbox="-0.0498162 -5.96091 12.2751 9.14241" width="12.2751pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M536 404C536 423 520 448 491 448C445 448 398 404 308 283L286 338C255 416 242 448 217 448C182 448 138 402 92 341L111 321C149 368 169 378 178 378C188 378 198 363 214 320L254 212C185 117 138 65 107 65C98 65 85 69 82 75C79 82 73 86 65 86C44 86 23 60 23 39C23 7 44 -12 71 -12C119 -12 168 33 265 177L306 61C321 17 347 -12 373 -12C413 -12 465 33 507 96L491 119C459 84 432 60 413 60C395 60 378 92 358 148L321 250C341 279 369 310 389 332C417 363 439 382 456 382C466 382 475 376 481 368C486 361 492 358 496 358C513 358 536 381 536 404Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,7.202,3.132)"><path d="M389 0V32C297 38 291 46 291 118V635C234 613 175 595 109 583V556L161 554C203 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d="M153 550H386L412 615L406 623H120L82 318C104 327 142 338 184 338C294 338 347 275 347 187C347 112 305 39 221 39C160 39 119 71 97 89C88 97 80 96 71 90C59 80 50 67 49 57C48 45 52 36 66 23C80 9 123 -12 169 -12C221 -11 288 15 342 59C403 109 431 165 431 225C431 308 366 395 238 395C212 395 165 379 127 364L153 550Z"></path></g></svg> for firm 2 for (a) Vidale–Wolfe model expressed in equation (<a href="https://static-preview.hindawi.com/articles/complexity/volume-2020/5371492/figures/#EEq20">20</a>) and (b) extended Lanchester model expressed in equation (<a href="https://static-preview.hindawi.com/articles/complexity/volume-2020/5371492/figures/#EEq25">25</a>). It is observed that the models have the same equilibrium point but different dynamics.</div>

Complexity

fig5

Figure 5

Figure 5: Dynamics of Duopoly Models with Undecided Clients under Decentralized Affine Feedback Advertising Policies 