Re: Statistical Functions and Boxplots
I have a client who wants some data represented by boxplots. I've been unable to find software for CF which will automatically calculate and graph the required information (upper quartile, lower quartile, median) from raw data passed, so I need to find a way of performing these calculations myself and pass them to the graph software. We have a customer that we calculate quartiles for (CF6.1, SS2K) and in that application we draw line graphs and bar charts using jFreeChart, which I believe can do boxplots although we don't currently use that part of it. Worth a look if you don't mind doing Java. Quartiles are not what you said. In colloquial use they are what Jochem said, but our customer says a) it is one value, not a set of values b) the algorithm used by Excel is wrong As you know, the customer is always right. We do it their way, with some CF and SQL which is rather slow but not very complicated. Nick ~| Find out how CFTicket can increase your company's customer support efficiency by 100% http://www.houseoffusion.com/banners/view.cfm?bannerid=49 Message: http://www.houseoffusion.com/lists.cfm/link=i:4:209107 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations Support: http://www.houseoffusion.com/tiny.cfm/54
Statistical Functions and Boxplots
I have a client who wants some data represented by boxplots. I've been unable to find software for CF which will automatically calculate and graph the required information (upper quartile, lower quartile, median) from raw data passed, so I need to find a way of performing these calculations myself and pass them to the graph software. I've got a Median function from cflib.org http://cflib.org but where things fall apart slightly is in the calculation of the upper and lower quartiles. I had been taught that to calculate these, you find the average of the top and bottom half of the dataset respectively. However, when I put the dataset into Excel and use its statistical functions, the results are slightly different. Further investigation has shown that there are a few ways of calculating quartiles but this is where I start getting out of my depth. Does anyone know: a) Is there any graphing software compatible with CF which can create boxplots from raw data? I've looked at ChartFX Statistical but it's only available for .NET. b) Is there software or functions around which can quickly and accurately calculate quartiles? I'm using CF5 by the way. Thanks, Ryan ~| Logware (www.logware.us): a new and convenient web-based time tracking application. Start tracking and documenting hours spent on a project or with a client with Logware today. Try it for free with a 15 day trial account. http://www.houseoffusion.com/banners/view.cfm?bannerid=67 Message: http://www.houseoffusion.com/lists.cfm/link=i:4:208973 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations Support: http://www.houseoffusion.com/tiny.cfm/54
Re: Statistical Functions and Boxplots
Ryan Edgar wrote: I have a client who wants some data represented by boxplots. I've been unable to find software for CF which will automatically calculate and graph the required information (upper quartile, lower quartile, median) from raw data passed, so I need to find a way of performing these calculations myself and pass them to the graph software. I've got a Median function from cflib.org http://cflib.org but where things fall apart slightly is in the calculation of the upper and lower quartiles. I had been taught that to calculate these, you find the average of the top and bottom half of the dataset respectively. I have been taught that the top quartile is the 25% of data points with the highest values :) Where do you get these data from? If you get them from a database, what native functions does that database have for doing statistics? For instance, PostgreSQL has the R language for statistical computing as a loadable module and you can use it as a procedural language. Jochem ~| Logware (www.logware.us): a new and convenient web-based time tracking application. Start tracking and documenting hours spent on a project or with a client with Logware today. Try it for free with a 15 day trial account. http://www.houseoffusion.com/banners/view.cfm?bannerid=67 Message: http://www.houseoffusion.com/lists.cfm/link=i:4:209015 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations Support: http://www.houseoffusion.com/tiny.cfm/54
Re: Statistical Functions and Boxplots
Sorry, should have said I'm using MS SQL 2000. I'm pulling data from survey results which will have a value in the range 1 - 5 so if I have 50 surveys, I'll want to find the max, min, upper and lower quartiles and median of the dataset for each individual quesion. i.e. 1 question = 1 box in the graphical output. Failing that, is there any way I can get Excel to generate these charts on the fly if I dump the data into a spreadsheet (automatically on the server)? At the end of the day the client wants a boxplot to be generated and isn't too concerned about how we go about getting it, as long as he doesn't have to do any work! Thanks, Ryan On 6/8/05, Jochem van Dieten [EMAIL PROTECTED] wrote: Ryan Edgar wrote: I have a client who wants some data represented by boxplots. I've been unable to find software for CF which will automatically calculate and graph the required information (upper quartile, lower quartile, median) from raw data passed, so I need to find a way of performing these calculations myself and pass them to the graph software. I've got a Median function from cflib.org http://cflib.org http://cflib.org but where things fall apart slightly is in the calculation of the upper and lower quartiles. I had been taught that to calculate these, you find the average of the top and bottom half of the dataset respectively. I have been taught that the top quartile is the 25% of data points with the highest values :) Where do you get these data from? If you get them from a database, what native functions does that database have for doing statistics? For instance, PostgreSQL has the R language for statistical computing as a loadable module and you can use it as a procedural language. Jochem ~| Find out how CFTicket can increase your company's customer support efficiency by 100% http://www.houseoffusion.com/banners/view.cfm?bannerid=49 Message: http://www.houseoffusion.com/lists.cfm/link=i:4:209040 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations Support: http://www.houseoffusion.com/tiny.cfm/54
Re: Statistical Functions and Boxplots
Ryan Edgar wrote: Sorry, should have said I'm using MS SQL 2000. I'm pulling data from survey results which will have a value in the range 1 - 5 so if I have 50 surveys, I'll want to find the max, min, upper and lower quartiles and median of the dataset for each individual quesion. i.e. 1 question = 1 box in the graphical output. Those aren't really hard to do just in SQL: SELECT MAX(dataset) as max, MIN(dataset) as min, Count(dataset) as freedom FROM table; SELECT TOP (.25 * freedom) dataset as upper FROM table ORDER BY dataset; SELECT TOP (.5 * freedom) dataset as mean FROM table ORDER BY dataset; SELECT TOP (.75 * freedom) dataset as lower FROM table ORDER BY dataset; Jochem ~| Logware (www.logware.us): a new and convenient web-based time tracking application. Start tracking and documenting hours spent on a project or with a client with Logware today. Try it for free with a 15 day trial account. http://www.houseoffusion.com/banners/view.cfm?bannerid=67 Message: http://www.houseoffusion.com/lists.cfm/link=i:4:209043 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations Support: http://www.houseoffusion.com/tiny.cfm/54
