Why do we call "Pretrained model"

zeus: <p>What I understood is that a</p>
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<p>model is the result of a training algorithm.</p>
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<p>Set of parameters learned by the training algorithm is model</p>
<p>Since a model is already a trained one,then why do we say “Pretrained models” .</p>
<p>If there are any misconception,please correct me.<br>
If my understanding is wrong, please explain the difference between a model and algorithm.</p>

Usama_Hasan: <aside class="quote no-group" data-username="zeus" data-post="1" data-topic="90397">
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<img loading="lazy" alt="" width="24" height="24" src="https://discuss.pytorch.org/letter_avatar_proxy/v4/letter/z/a4c791/48.png" class="avatar"> zeus:</div>
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<p>model is the result of a training algorithm.</p>
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<p>A model is a group of algorithm which are stacked together to learn to solve complex problem.</p>
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<img loading="lazy" alt="" width="24" height="24" src="https://discuss.pytorch.org/letter_avatar_proxy/v4/letter/z/a4c791/48.png" class="avatar"> zeus:</div>
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<p>Then why do we say “Pretrained models” because we know that a model is already a trained one.</p>
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<p>Yes, a Pre-trained model is one which is already trained on some dataset.</p>

zeus: <p>Thanks for the response. I am having a confusion in the term usage. Model is the outcome of a training algorithm. So the term “model” itself means “pre trained”. Then why do we use “pretrained model”.</p>

Usama_Hasan: <aside class="quote no-group" data-username="zeus" data-post="3" data-topic="90397">
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<img loading="lazy" alt="" width="24" height="24" src="https://discuss.pytorch.org/letter_avatar_proxy/v4/letter/z/a4c791/48.png" class="avatar"> zeus:</div>
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<p>Model is the outcome of a training algorithm.</p>
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<p>Yes, we do quote it like this in machine learning.<br>
The term pre-trained model is originated from transfer learning, in which we re-use that model to train/test it on some other dataset to obtain results. See most of the cases where we quote pre-trained we actually use them to extract feature or embedding not the whole model itself.<br>
I guess this makes some sense.</p>

zeus: <p>Thanks for the explanation. I still have doubt on the term, but anyways I am gonna use the term “pretrained model”. Resnet,vgg are architectures not models,right?</p>

Usama_Hasan: <aside class="quote no-group" data-username="zeus" data-post="5" data-topic="90397">
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<img loading="lazy" alt="" width="24" height="24" src="https://discuss.pytorch.org/letter_avatar_proxy/v4/letter/z/a4c791/48.png" class="avatar"> zeus:</div>
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<p>Resnet,vgg are architectures not models,</p>
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<p>See, the literature is full of different terminologies, they are models which are sometimes called deep learning architectures too.</p>

zeus: <p>Okay. Thanks for your answers and patience.</p>