Change Details

Split off from T155639. More details on this work are documented [[ https://meta.wikimedia.org/wiki/Research_talk:Reading_time/Work_log/2018-09-25#Consistency_Checks | here ]] and [[https://meta.wikimedia.org/wiki/Research_talk:Reading_time | here]]. E.g. [x] Having found that there are sometimes page tokens (pageviews) with > 2 events, check that at least there is only one pageloaded event among them each time There are 0.0111% of events where page loaded happened more than once. [X] Check if such pageviews (tokens) with multiple unloaded events will need to be filtered out during analysis, or whether their impact is likely small enough to be ignored 0.311% of pageviews have more than one unloaded events. We are filtering them out in the [[ https://meta.wikimedia.org/wiki/Research:Reading_time | Reading time project]]. [X] Consistency checks: `totalLength` and `visibleLength` should be less (apart from rounding errors) than the difference between timestamps of the loaded and unloaded events (@zareenf already worked on these) We have about 7% of cases where the lengths these are more than 2 seconds greater than the difference between the time stamps and about 1.5% of cases at more than 5 seconds apart. We also [[ https://meta.wikimedia.org/wiki/Research_talk:Reading_time/Work_log/2018-09-25#/media/File:LengthErrorDistribution.png | observe periodicity ]] in the distribution errors with a periodicity of about 40 seconds. We are investigating this further [X] Generate histogram for `totalLength` [X] Generate histograms for `visibleLength` [[ https://meta.wikimedia.org/wiki/Research_talk:Reading_time/Work_log/2018-09-25#/media/File:WP_ReadingTime_Distributions.png | Here's a plot with of the distribution of the lengths (logged) ]] [X] Investigate cause of periodicity in discrepancies between total/visibleLength and event timestamps. This was an artifact of a bug parsing datetimes. [[https://upload.wikimedia.org/wikipedia/commons/thumb/9/95/Plot_reading_time_discrepencies_overall.png/600px-Plot_reading_time_discrepencies_overall.png | This plot shows the distribution of discrepancies with the bug fixed.]] [ ] Investigate cause of total/visibleLength values that are negative or very large. (See also [[https://docs.google.com/document/d/15PDd09AbFlrcr9hYWWcrqi7hup71jSUjxfywjXAZ2QU/edit | notes]])

Split off from T155639. More details on this work are documented [[ https://meta.wikimedia.org/wiki/Research_talk:Reading_time/Work_log/2018-09-25#Consistency_Checks | here ]] and [[https://meta.wikimedia.org/wiki/Research_talk:Reading_time | here]]. E.g. [x] Having found that there are sometimes page tokens (pageviews) with > 2 events, check that at least there is only one pageloaded event among them each time There are 0.0111% of events where page loaded happened more than once. [X] Check if such pageviews (tokens) with multiple unloaded events will need to be filtered out during analysis, or whether their impact is likely small enough to be ignored 0.311% of pageviews have more than one unloaded events. We are filtering them out in the [[ https://meta.wikimedia.org/wiki/Research:Reading_time | Reading time project]]. [X] Consistency checks: `totalLength` and `visibleLength` should be less (apart from rounding errors) than the difference between timestamps of the loaded and unloaded events (@zareenf already worked on these) We have about 7% of cases where the lengths these are more than 2 seconds greater than the difference between the time stamps and about 1.5% of cases at more than 5 seconds apart. We also [[ https://meta.wikimedia.org/wiki/Research_talk:Reading_time/Work_log/2018-09-25#/media/File:LengthErrorDistribution.png | observe periodicity ]] in the distribution errors with a periodicity of about 40 seconds. We are investigating this further [X] Generate histogram for `totalLength` [X] Generate histograms for `visibleLength` [[ https://meta.wikimedia.org/wiki/Research_talk:Reading_time/Work_log/2018-09-25#/media/File:WP_ReadingTime_Distributions.png | Here's a plot with of the distribution of the lengths (logged) ]] [X] Investigate cause of periodicity in discrepancies between total/visibleLength and event timestamps. This was an artifact of a bug parsing datetimes. [[https://upload.wikimedia.org/wikipedia/commons/thumb/9/95/Plot_reading_time_discrepencies_overall.png/600px-Plot_reading_time_discrepencies_overall.png | This plot shows the distribution of discrepancies with the bug fixed.]] [X] Investigate cause of total/visibleLength values that are negative or very large. We did not see any patterns of negative values. However, we do observe a still-unexplained periodicity in the frequency of negative . Only 0.0019% of events have a negative totallength and 0.010% of events have a negative visible length. Only 2.77% of events have a total length greater than 1 hour, and 1.03% of events have a visible length greater than 1 hour. Only 0.189% of events have a total length greater than 12 hours, and 0.460% of events have a visible length greater than 12 hours. As these number are quite small, especially in the negative cases, I do not feel that urgent investigation of this matter is urgent. (See also [[https://docs.google.com/document/d/15PDd09AbFlrcr9hYWWcrqi7hup71jSUjxfywjXAZ2QU/edit | notes]])

Split off from T155639. More details on this work are documented [[ https://meta.wikimedia.org/wiki/Research_talk:Reading_time/Work_log/2018-09-25#Consistency_Checks | here ]] and [[https://meta.wikimedia.org/wiki/Research_talk:Reading_time | here]]. E.g. [x] Having found that there are sometimes page tokens (pageviews) with > 2 events, check that at least there is only one pageloaded event among them each time There are 0.0111% of events where page loaded happened more than once. [X] Check if such pageviews (tokens) with multiple unloaded events will need to be filtered out during analysis, or whether their impact is likely small enough to be ignored 0.311% of pageviews have more than one unloaded events. We are filtering them out in the [[ https://meta.wikimedia.org/wiki/Research:Reading_time | Reading time project]]. [X] Consistency checks: `totalLength` and `visibleLength` should be less (apart from rounding errors) than the difference between timestamps of the loaded and unloaded events (@zareenf already worked on these) We have about 7% of cases where the lengths these are more than 2 seconds greater than the difference between the time stamps and about 1.5% of cases at more than 5 seconds apart. We also [[ https://meta.wikimedia.org/wiki/Research_talk:Reading_time/Work_log/2018-09-25#/media/File:LengthErrorDistribution.png | observe periodicity ]] in the distribution errors with a periodicity of about 40 seconds. We are investigating this further [X] Generate histogram for `totalLength` [X] Generate histograms for `visibleLength` [[ https://meta.wikimedia.org/wiki/Research_talk:Reading_time/Work_log/2018-09-25#/media/File:WP_ReadingTime_Distributions.png | Here's a plot with of the distribution of the lengths (logged) ]] [X] Investigate cause of periodicity in discrepancies between total/visibleLength and event timestamps. This was an artifact of a bug parsing datetimes. [[https://upload.wikimedia.org/wikipedia/commons/thumb/9/95/Plot_reading_time_discrepencies_overall.png/600px-Plot_reading_time_discrepencies_overall.png | This plot shows the distribution of discrepancies with the bug fixed.]] [ X] Investigate cause of total/visibleLength values that are negative or very large. We did not see any patterns of negative values. However, we do observe a still-unexplained periodicity in the frequency of negative . Only 0.0019% of events have a negative totallength and 0.010% of events have a negative visible length. Only 2.77% of events have a total length greater than 1 hour, and 1.03% of events have a visible length greater than 1 hour. Only 0.189% of events have a total length greater than 12 hours, and 0.460% of events have a visible length greater than 12 hours. As these number are quite small, especially in the negative cases, I do not feel that urgent investigation of this matter is urgent. (See also [[https://docs.google.com/document/d/15PDd09AbFlrcr9hYWWcrqi7hup71jSUjxfywjXAZ2QU/edit | notes]])