Though there is general rule for measuring ROI on training, it is important to customise the measures. You have not mentioned the nature of the industry or the finished product or service of the company for which you have applied for the post of Training Manager.
As far as ROI on training is concerned, there are large number of posts available on this forum. You could have checked this forum. I have also given sufficient number of replies on such posts. You may click the following link to refer the replies:
(though this is related to technical training, the comments are useful to behavioural training as well)
I recommend you going through the above links patiently. It will enhance your training awareness.
Final comments: - For any training to be successful, you need to measure the costs associated with the business. Measurement of training is cost before the training and cost after the training. Though measurement of ROI on training is simple, measuring the costs and designing training programmes to reduce the costs is not simple.
All the best!