Resnet 50 v1.5 definition

jujubi: <p>Like to see the exact network architecture of resnet v1.5.</p>
<p>I see two references:<br>
<a href="https://github.com/tensorflow/models/tree/master/official/resnet" rel="noopener nofollow ugc">https://github.com/tensorflow/models/tree/master/official/resnet</a><br>
“where a stride 2 is used on the 3x3 conv rather than the first 1x1 in the bottleneck”</p>
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<h3><a href="https://github.com/facebookarchive/fb.resnet.torch" target="_blank" rel="noopener nofollow ugc">GitHub - facebookarchive/fb.resnet.torch: Torch implementation of ResNet from...</a></h3>

  <p>Torch implementation of ResNet from http://arxiv.org/abs/1512.03385 and training scripts - GitHub - facebookarchive/fb.resnet.torch: Torch implementation of ResNet from http://arxiv.org/abs/1512.03...</p>


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" <strong>Strided convolution</strong> : When using the bottleneck architecture, we use stride 2 in the 3x3 convolution, instead of the first 1x1 convolution."</p>
<p>I have two questions.</p>
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<p>From the table in the resnet paper: <a href="https://arxiv.org/pdf/1512.03385.pdf" rel="noopener nofollow ugc">https://arxiv.org/pdf/1512.03385.pdf</a><br>
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“Downsampling is performed by conv3 1, conv4 1, and conv5 1 with a stride of 2.”,<br>
In v1.5, these 1x1 convolutions of stride 2 are removed and the following 3x3 is made into stride 2? (That would make sense) So, just 3 1x1 convolution blocks are removed and the 3 3x3 convolutions are made into stride 2?</p>
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<p>Is this all the changes?</p>
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Dirtybluer: <p>Answer 1: In ResNet v1.5, 1x1 convolution layers <strong>haven’t been removed</strong> but modified to have a stride of 1 instead of 2. Meanwhile, the original 3x3 convolution layers have been modified to have a stride of 2 instead of 1. In summary, the previous downsample responsibility has been transferred from the first 1x1 convolution layer to the 3x3 convolution layer of Bottlenecks.</p>
<p>Answer 2: All the changes are as above.</p>
<p>Besides, I’d like to know where the name “V1.5” comes from since I can’t find the source of it. Hope someone could offer a source link.</p>