## 2019-06-27

### Continent-Based DX in CQ WW: 2007

This post shows the number of QSOs for pairs of continents from the CQ WW contests for 2007. The plots are created from the augmented file (cq-ww-2005--2018-augmented.xz; see here for details of the augmented format) derived from the public logs.

The procedure is simple and is equivalent to that used for the zone-based analyses. We consider only QSOs that meet the following criteria:
1. marked as "two-way" QSOs (i.e., both parties submitted a log containing the QSO);
2. no callsign or zone is bust by either party.
A counter is maintained for every pair of continents and the pertinent counter is incremented once for each distinct QSO between stations in those continents.

Separate figures are provided for each band, led by a figure integrating QSOs on all bands. The figures are constructed in such a way as to show the results for both the SSB and CW contests on a single figure. (Any pair of continents with no QSOs that meet the above criteria appears in black on the figures.)

### Continents and Distance

We can also examine the distribution of distance for QSOs as a function of continent.

Below is a series of figures showing this distribution integrated over all bands and, separately, band by band for the CQ WW SSB and CQ WW CW contests for 2007.

Each plot shows a colour-coded distribution of the distance of QSOs for each continent, with the data for SSB appearing above the data for CW within each continent.

For every half-QSO in a given continent, the distance of the QSO is calculated; in ths way, the total  number of half-QSOs in bins of width 500 km is accumulated. Once all the QSOs for a particular contest have been binned in this manner, the distribution for each continent is normalised to total 100% and the result coded by colour and plotted. The mean distance for each continent and mode is denoted by a small white rectangle added to the underlying distance distribution. The 99% confidence range of the value of mean is marked by a small blue rectangle (typically entirely subsumed by the white rectangle). The median is marked with a vertical brown rectangle.

As usual, only QSOs for which logs have been provided by both parties, and which show no bust of either callsign or zone number are included. Bins coloured black are those for which no QSOs are present at the relevant distance.

The resulting plots are reproduced below.