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5. Use cases

Now that we've got nice reports, and a deep warm feeling of being scientifically valid, one may wonder -- what's the actual practical point? Well, in addition to having firm data for further hit prob analysis (such as, for example, Bryan Litz's excellent WEZ modelling), there are a few immediate practical uses, mostly relying on knowledge of confidence intervals:

Load development

Q: How do we know if load A is better than load B?
A: We shoot until confidence intervals no longer overlap.

4.5. Pulling analytic reports

Two buttons --

One -- save report:

Saves the analysis report, as it appears on the screen, to a vector image file in SVG format.

Two -- export shots table:

Saves the project shots as a table in CSV format (can be opened by Excel, Libreoffice/Openoffice Calc, etc.) for further analysis. The co-ordinates of shots are in real units (mm or inches, depending on project settings), relative to PoA.

4.4. Confidence

Proper confidence intervals is probably the most valuable feature of TARAN, as it allows you to know how much you can trust your measures (and also, incidentally, to discard statistically invalid bullshit claims).

4.3. Hit probability calculator

Notice the slider 0%..99%.

It is a basic hit probability calculator. Any non-zero position of the slider displays a red circle with the associated radius and hit probability.

Of course, it only works for the same conditions as for the project targets -- specifically, the same distance -- but can be a valuable tool for classic (ISSF or CISM) sport shooters, for score estimation, and can also provide an immediate answer to idle questions like "how likely am I to hit a 1 MOA circle".

4.2. Measures of precision

As mentioned here and here, a single group's extreme spread as a measure of rifle precision is both scientifically invalid and practically useless.

Rifle precision can, however, be rather accurately described by known statistical models. TARAN uses the Rayleigh distribution model to calculate precision parameters. The outcome of the modelling is presented in the left-hand pane:

4.1. Point of impact

In the centre, the orange circle represents the average PoI for all shots from all groups. Basically, it tells you how much off is your scope zero from the PoA (red circle).

The pale orange area around the average PoI is error margin. The error margin corresponds to 95% confidence, and, strictly speaking, means that if I shot an infinite number of similar projects, in 95% of the cases the true average PoI would be somewhere in this pale orange area (which may be different for each project).

4. Analysis pane

When we're done with all targets and all groups in the project, we can switch to Analysis pane

The analysis pane is why TARAN has been written in the first place (the rest of it is just callipers with attitude).

It represents aggregated data from all shots registered in the project. As a reference, a 1MOA circle is drawn in dotted orange.

3. Targets management (back to the project pane)

Once we're done with a target, we can get back to the project pane to add more targets to the project, and have a general overview.

"Add target", as you can guess, adds a new target.

To delete a target from the project, click on the target header with the "Delete target" icon

Clicking on a target image selects it and switches to the Target pane.

2.5. Target image export

Suppose I have shot some beautiful groups, and want to show off on my favourite Internet forum. TARAN has a feature for that:

The "Export image" button saves the current target image with all marked groups and shots.
- The target image is saved at the current zoom level
- All groups are selected, with ES and average PoI info boxes displayed
- The image is stamped with the project parameters (project title, distance, calibre), software version and timestamp

2.4. Multiple groups on the same target

Of course, you can. Just mark a new PoA, and it starts a new group.

The lower group is selected -- it has extreme spread displayed, and appears in brighter colours.

You can select a group either by clicking on the group's PoA, or -- notice changes in the left-hand navigation pane:


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by Dr. Radut