planetqhe and the IB

Random Behaviour

Experimental vs Theoretical

Compound Events I

Compound Events II

Expectations and Distributions

Distributions and Hypotheses

Probability in the real world



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Technical Notes:

The majority of the spreadsheets in this site make use of Microsoft Excel, and its random number generator. Every time you press the F9 key on your computer, Excel generates random numbers (with the RANDBETWEEN function and recalculates the spreadsheet according to how I have programmed the sheet, so every F9 gives you another trial of the experiment. All the 'working out' is hidden behind the graphs or blanked out by setting the font colour the same as the background - its easy to alter this and have a look at how I programmed the activities. Some of the spreadsheets keep running totals of successes and these spreadsheets also feature Reset buttons. Please note that for technical reasons, I cannot program these buttons to start with zero for all registers, so there is a small built-in bias, but for a lot of large trials it is negligable.

You can use these features to collect data and import the data into a statistics programme like Autograph. For example see the exemplar from the planetqhe and the IB section. 

In order to run the Excel spreadsheets, you'll need to have the Analysis ToolPak Add-In installed. It's really easy to do. Just open up Excel and go to Tools on the menu bar, and follow: Tools->Add-Ins->Analysis ToolPak (check box). This gives Excel the functionality to create random numbers each time you press F9 and update your spreadsheet accordingly. You can either run these spreadsheets in your browser, or - in the case of Birthdays USA 1978, Experiment two and Radioactive decay spreadsheets, you might want to download them directly to your own computer by right-clicking on the "enter activity" buttons and choosing "save target as". (These activities require you to add formulae or charts to the sheet).

I have programmed some macros in the Experiment one, Families Special Dice, Birthdays, Maternity, Chevalier de Mere and Alex/Beth spreadsheets. Your computer will tell you this and warn you not to open them unless you trust the writer of the macros not to slip in a virus. You can trust me - but of course the usual provisos apply - no responsibility accepted.

One file - The Birthday Problem- uses the FATHOM dynamic statistics application. If you don't have it, Download the Fathom Demo but remember that this version will not let you print nor save. 

Tech Help for the Families, Special Dice, Birthdays, Maternity and Chevalier de Mere spreadsheets;
the tallying of scores requires the use of a circular formula which is not allowed in the normal calculation mode. So we need to do the following; Tools-Options-Calculation-Automatic Iteration - Maximum Iterations 1 - OK

The spreadsheets are sized between 37K and 353K so they do take some time to download. Please be patient.

If you do not have Microsoft Excel installed on your computer don't panic - you can download a free Excel viewer here.