how important is start time for time frame bars

[bigdavediode]

Quote from zedDoubleNaught:

Highs and lows are the only values that will be consistent, opens and closes can vary based on the time sampling.

Choosing different sample intervals or times becomes one method of smoothing.

So why would you think that highs and lows offer less noise? After all, they're only the highs and lows of fat-tailed, noisy data.

Try an experiment: try your highs and lows charting based on different start times and see how they compare to each other. I believe you'll find it's similarly erratic to your original method.

 

[Zr1Trader]

A Bullish hammer with a long tail on the 5 min for example could look like 1 red bar followed by 1 greenbar on the 2 min . It's understanding the price action and context that matters. But yes your millage may vary with indicators and different time frames if you are using a bar close sensitive approach . Range bars might help fix the issue.

 

[abetworth]

The likes of Steve Nison teach how to blend candles. When you have looked at them for long enough you start to see the patterns regardless of timeframe. Multiple brokers (demo is fine) is one option for different daily start times etc.

Quote from zedDoubleNaught:

I've read lots from various sources that goes along the lines of "wait for the bar to close over the XXX indicator", or another example is candlestick patterns that depend on the O-H-L-C values for the shape of the candle.
However, I think it is possible to change the shape of the candles, or candle patterns, or whether the close/open is around an indicator, by changing when the interval starts.
In the attached example, it is an hourly chart; usually charts start the bar on the hour, and close it before the next hour. For my study, I've extracted hourly bars from 5-minute data, starting on the hour (ex, 1:00, 2:00, 3:00 ...). For the comparison, I start the bar at the half hour (ex, 1:30, 2:30, 3:30 ...).

The 2 look generally close but with some differences. I marked 3 examples that stood out to me with blue arrows and labeled as 1, 2, 3. (I think they match up as the corresponding bars.)

In case 1, the On-the-Hour shows a tall wick and a short body. But the On-the-Half-Hour, these are 2 bars with long bodies, and no wick. Additionally, if you were looking for a close over an indicator, I'd guess the On-the-Hour would probably not signal, whereas the On-the-Half-Hour would.

Are these types of differences significant? Or do they somehow balance out with a large enough data set? I suppose they would affect pattern recognition or technical signals, the patterns or signals could change based on when the summarizing bar starts and ends. I suppose this is why they say draw trend lines or patterns based on highs and lows instead of closes, they seem to have consistent values between the 2 interpolations.