ditor Comments Associate Editor Comments to the Author: We apologize for the delayed reviews. We received two very positive reviews for the paper. Both reviewers have requested minor edits and one of the reviewer has asked for a more substantial rewrite. We are still awaiting reviews from a third reviewer. But given the overall positive reviews, we recommend a minor revision for the paper and hope the authors can quickly address these comments. ******************** Reviewer Comments Please note that some reviewers may have included additional comments in a separate file. If a review contains the note “see the attached file” under Section III A – Public Comments, you will need to log on to ScholarOne Manuscripts to view the file. After logging in, select the Author Center, click on the “Manuscripts with Decisions” queue and then clicking on the “view decision letter” link for this manuscript. You must scroll down to the very bottom of the letter to see the file(s), if any. This will open the file that the reviewer(s) or the associate editor included for you along with their review. Reviewer: 1 Recommendation: Author Should Prepare A Minor Revision Comments: The work as it stands is good: the framework is well defined, comparisons to existing literature are good, and performance on the real-world data is compelling. From the text, narrowing down why the two versions MWS-stdscr are better than existing work is difficult primarily due to too many independent variables. Specifically, is it due to using the median values during the week as opposed to average; or due to agglomerate clustering rather than k-means? Given that the daily and denoised version of MWS were previously shown to not improve results, space could have been better used in this case toward understanding why the MWS-stdscr family does so well. In Figure 3, university identification seems to have a much different result pattern than other classes. It would nice to get the authors' thoughts on why this is the case. Signature analysis -- Section 5 and beyond -- is a good addition to the existing work. The work, as an overall package, is solid. The ideas are a nice contribution, and there seem to be no glaring errors. Thus, the aforementioned suggestions should be considered if there is space, or as potential future work otherwise. The "necessary" changes that this reviewer recommends are thus minor: Page 14, Line 36, Column 2: behaviour is misspelled Page 9, Line 23, Column 1: "is" should be "are" Page 1, Line 23, Column 2; Page 14, Line 57, Column 2: Use the word "neat" is ambiguous. Is this neat in the "cool" sense, or neat in the "clean" sense. Finding a more accurate word is suggested. Page 13 Line 57, Column 2: The use of "believers" could be softened. For example, a more neutral sentence might be "... which regularly gather a large, diverse, and heavily mobile audience." Reference 32: This reference is used to backup the definition of entropy. In the reviewers addition of the book, the definition is Chapter 5 rather than Chapter 8. It is thus suggested that the reference be augmented to not include chapter and page information. Additional Questions: 1. Which category describes this manuscript?: Practice / Application / Case Study / Experience Report 2. How relevant is this manuscript to the readers of this periodical? Please explain under Public Comments below. : Very Relevant 1. Please explain how this manuscript advances this field of research and/or contributes something new to the literature. : The authors review their previously proposed novel technique for identifying and classifying mobile data signatures. They compare their method to the state-of-the-art, which includes methods not considered in their initial publication. They go on to test their methodology on a large real-world data set, and make a good argument as to the usefulness of their proposed technique. 2. Is the manuscript technically sound? Please explain under Public Comments below. : Yes 1. Are the title, abstract, and keywords appropriate? Please explain under Public Comments below. : Yes 2. Does the manuscript contain sufficient and appropriate references? Please explain under Public Comments below. : References are sufficient and appropriate 3. Does the introduction state the objectives of the manuscript in terms that encourage the reader to read on? Please explain under Public Comments below. : Yes 4. How would you rate the organization of the manuscript? Is it focused? Is the length appropriate for the topic? Please explain under Public Comments below. : Satisfactory 5. Please rate the readability of this manuscript. Please explain your rating under Public Comments below. : Easy to read 6. Should the supplemental material be included? (Click on the Supplementary Files icon to view files): Does not apply, no supplementary files included 7. If yes to 6, should it be accepted: 8. If this manuscript is an extended version of a conference publication, does it offer substantive novel contributions beyond those of the previously published work(s)- i.e. expansion of key ideas, examples, elaborations etc. *New results are not required*: Yes Please rate the manuscript. Please explain under Public Comments below. : Excellent Reviewer: 2 Recommendation: Author Should Prepare A Minor Revision Comments: This is a fascinating paper with lots of very interesting observations presenting a detailed analysis of mobile traffic across several urban contexts. I have only one reservation on this paper which can be addressed easily. The takeaways and the results are a bit all over the place and the authors need to revise the presentation significantly to outline the "key observations" and results. The paper is overlaid with both obvious and not-so obvious results. The authors need to delineate these two aspects quite carefully. The second aspect is that some of the urban characteristics naturally follow from population distributions across specific dimensions including office distributions etc. How many of these observations are really a natural artifact of the population distribution and how many of your observations go beyond these simple stats. You make a comparison across ten cities. How are these cities different? The takeaways comparing across cities were not outlined clearly. Overall, this has potential to be a fantastic paper, if the authors can rewrite the paper to outline their contributions and whats novel about their results across cities. Additional Questions: 1. Which category describes this manuscript?: Research/Technology 2. How relevant is this manuscript to the readers of this periodical? Please explain under Public Comments below. : Very Relevant 1. Please explain how this manuscript advances this field of research and/or contributes something new to the literature. : This paper uses cellular usage traces to perform a detailed urban informatics analysis of mobile traffic. The paper analyzes the traffic characteristics across a broad spectrum of axes and have several interesting observations. 2. Is the manuscript technically sound? Please explain under Public Comments below. : Yes 1. Are the title, abstract, and keywords appropriate? Please explain under Public Comments below. : Yes 2. Does the manuscript contain sufficient and appropriate references? Please explain under Public Comments below. : References are sufficient and appropriate 3. Does the introduction state the objectives of the manuscript in terms that encourage the reader to read on? Please explain under Public Comments below. : Yes 4. How would you rate the organization of the manuscript? Is it focused? Is the length appropriate for the topic? Please explain under Public Comments below. : Could be improved 5. Please rate the readability of this manuscript. Please explain your rating under Public Comments below. : Easy to read 6. Should the supplemental material be included? (Click on the Supplementary Files icon to view files): Does not apply, no supplementary files included 7. If yes to 6, should it be accepted: 8. If this manuscript is an extended version of a conference publication, does it offer substantive novel contributions beyond those of the previously published work(s)- i.e. expansion of key ideas, examples, elaborations etc. *New results are not required*: Yes Please rate the manuscript. Please explain under Public Comments below. : Excellent