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Jim Chapple is now working full time on iphone/ipod touch and iPad applications.
Jim Chapple also works on Mac OS X Apps.
Please email Jim Chapple for support issues, information and quotes.
Spread Calculator
- Do you need to know how to work out the Standard Deviation, the range and the interquartile numbers for a set of values?
- This App takes the value you supply and generates three differing standard deviation values, the range, the upper and lower quartile values and the interquartile range.
- This App also comprehensively explains how these answers were arrived at so that you can learn for yourself.
The small thumbnail images below will show larger screenshots.
FAQ: This App does not work properly it keeps on crashing, why?
Sometimes Apps just do not download properly. You will need to download it again, for free, using itunes. See Apple Support Pages
About half way down the page there's a set of instructions that starts 'Reinstall the affected application'.
Once iTunes has it then you sync your device and it should then work. If it does not then please to contact me.
The main pageClick on the field at the top and use the keypad to enter the values. Separate the values using a space. When you have entered all the numbers then select OK. The various values are calculated for you. The first two standard deviation methods assume that the values specified are all of the values. This is the STDEVP function in Excel. The third standard deviation method assumes that the values specified are only a subset of the total values. This is the STDEV function in Excel. The App calculates the range of the values, the upper and lower quartiles and the interquartile range. |
The WorkingsThe workings explain how all of the answers were calculated using the values you supplied. They are intended to help you learn how to generate the answers for yourself. The blue background parts are generalised explanations while the white background parts use the values you supplied to show the calculations. |
The keypadUse the keypad to enter all of the values. Each value must be separated by a space. Decimal numbers are allowed. Use the 'Del' key to delete the last character entered. Use the 'OK' to dismiss the keypad and have the App calculate the new answers. The workings will also be updated at this point. |