Yesterday we blogged about how out of whack David Cunliffe’s power graph was. We presented a nother view from the same data.
Another reader has emailed with his thoughts.
Haven’t really followed the arguments aroundÂ powerÂ prices. But what really grinds my gears is bad data analysis. I have done quite a bit of normalizing of data in my time and although it is a powerful tool, it has to be used with caution because it can really skew the data. As soon as I saw Labours press release I was suspicious about why they chose to normalize to the date they did.
Thanks to previous correspondent who made the raw data easily available, I normalized the data to 1990, as this was the closest data point to the reforms that people complain about. Also have blocked out via color who was inÂ power. Because of the data, I have “logged” the y-axis, so the changes are non-linear wrt this axis.
NZ is in black / bold. Shows that the price rise was not due to the early 90′s reforms. As there was almost no price increase from 1990 to year 2000. Furthermore the price was increasing before the reforms, then had reduced increases post reforms. So it is impossible to blame the reforms for the price increases.Â Read more »