error about "classification.lua"

[nottwy]

I run the command below
th classification.lua -input_image_path images/cat_dog.jpg -label 243 -gpuid -1

And I get such error message:

{
input_sz : 224
out_path : "output/"
seed : 123
label : 243
gpuid : -1
proto_file : "models/VGG_ILSVRC_16_layers_deploy.prototxt"
input_image_path : "images/cat_dog.jpg"
save_as_heatmap : 1
layer_name : "relu5_3"
backend : "nn"
model_file : "models/VGG_ILSVRC_16_layers.caffemodel"
output_image_name : ""
}
Couldn't load models/VGG_ILSVRC_16_layers.caffemodel
/home/nott/00.software/00.ml/torch/install/bin/luajit: classification.lua:48: attempt to index local 'cnn' (a nil value)
stack traceback:
classification.lua:48: in main chunk
[C]: in function 'dofile'
...0.ml/torch/install/lib/luarocks/rocks/trepl/scm-1/bin/th:150: in main chunk
[C]: at 0x00406460

I'm not sure why it's like this. Could you help me?