0

Real data collection with N = 2

Thu 24 May, 2012 11:10 am
I performed an actual scientific experiment and I was only able to collect 2 data points. I am wondering what kind of statistical method I can use to analyze the data.

I performed a similar experiment before where I was able to collect 4 data points. I calculated the mean, the standard deviation of the population and a confidence interval for this population of N = 4. Could I also calculate the same things for a population of N = 2 ?
• Topic Stats
• Top Replies
Type: Question • Score: 0 • Views: 2,063 • Replies: 3
No top replies

JPB

2
Thu 24 May, 2012 11:13 am
@karambole,
Sure, but the width of your confidence interval is going to be huge. The more values you have in your data set the more confidence you'll have in predicting the true mean of your data. N=4 isn't very large either. You usually want to see n=20 or more before your CI is going to have much value.
0 Replies

engineer

1
Thu 24 May, 2012 02:08 pm
@karambole,
What was your hypothesis? If you conduct a very well controlled experiment you might be able to use two data points to refute a hypothesis, but it depends on what you are doing.
farmerman

1
Thu 24 May, 2012 06:57 pm
@engineer,
The only thing I can clearly see where the two points would be valid, would be a "trend Line" that would continue data into a realm of low field confidence already.

In other words,it could be used with an analytical machine, say a geiger counter that would clearly and accurately trnslate counts into disintegrations per second. AT the lowest end of the counters quantitative limit we could extend its use by a trend line with two (or more) data points that extend the quantitative limit further down .
Single or double point quantitation points are often used to extend lab instruments useful fields into really low concentration levels.
0 Replies

Related Topics

1 in 5 women get raped? - Discussion by maxdancona
How will you die? - Discussion by Robert Gentel
Statistics - probability - Question by jrl06
Sampling formula - Question by Moses mbeya

1. Forums
2. » Real data collection with N = 2