significance test

1. Most appropriate statistical test for this nested design

I currently am conducting a study where I have three variables: one that is binary, and two numerical variables as measured on a ratio scale. Each of the subjects in my study has values for each of the three variables. Variables: Condition (binary): Values 0 and 1 Pre (ratio) Post...
2. [R] Difference between regression lines significant?

Hi, I'm a PhD student researching processes of technology maturation. For this purpose I collected patent data which I want to use to differentiate between 3-6 yet arbitrary maturtiy phases (e.g. technology introduction, growth, maturity, decline). For several different technologies I have...
3. (Using R) What’s the right test to compare for significance?

First of all, many thanks for looking at this post. My problem is partly technical knowledge (or lack of), but mainly one of perception! I’ve been searching the web, looking at forum posts, help files, etc, but can’t quite get my head around the issue to come up with a satisfactory answer...
4. Correlation and significance with dependent observations

Hi, I am trying to correlate two variables of which one variable has dependent observations as it is data derived from a social network. I am intending to use Spearman's rank correlation coefficient. As I understand conventional methods for significance test do not provide reliable results...
5. Testing Difference of Values from Lognormal Distribution?

I have data that fits a lognormal distribution really well. My primary goal is to create a statistical classifier using this distribution to apply to new data from the same source. Essentially, I have 2 possible values, I choose the bigger one (based on the lognormal density) and then attach a...
6. Significance testing between ratios

Hi, I'm working with employment data to compare my local region with Pennsylvania's employment as a whole. I'd like to determine whether differences from the overall ratio are significant, e.g. my region has 20.23% of PA's 5,426,530 jobs. But in, say, the Air Transportation sector, we have...
7. Intraclass Correlation Coefficients: Significant Difference when H0~=0?

I'm trying to determine whether two intraclass correlation coefficients are statistically significantly different. The catch is that the two samples are between subjects, and the null hypothesis is that the difference between rho1-rho2 = .5. I've done a Fisher's Z' transform, but the confidence...
8. How to check association between an interval variable & nominal variable?

There is a collection of data of 2000 patients. I want to know the age of onset of Diabetes (an interval variable) has any relationship to the presence or absence of Albumin in urine (a nominal variable). What is the best test I can use to check whether there is any significant association...
9. Which Significance test do I use?

Hi, I've just started a new stats unit and it turns out my brain is a little dustier than I first thought. Would someone be able to give me a hint about which significance test to use for these questions? Question 1 - A student plants 76 seedlings of a rare species to see if they will...
10. Which data types & correlation method?

Dear all, I'm a new graduate student and not yet proficient at statistics in research. Please help me confirm/correct the following questions. * I want to examine if streaming video viewing styles correlate with reading frequency, comprehension, and speed. 1. one kind of data is 4...