# Search results

1. ### Creating a scale with dichotomous and continuous items

Check out Principal Component Analysis
2. ### How to test this scenario?

So you have a population of all people, and four samples drawn from that population, called red, brown, blonde, and black. Since this is a problem where sample sizes differ, we should use a z-score that takes sample size into account. Normal z score = (observation - average)/(standard...
3. ### Cross-national comparison best methodology and research questions advice

I hypothesize attitudes toward justice correlate with annual wages. Does the survey taker earn more than the median for 1 person? More than ten people? Less than 1/5th?
4. ### Chance performance in a binary response task

80/100 = 4/5 of answers are true, 1/5 of answers are false. If the subject knows this, then their best guessing strategy is to guess true 4/5 of the time and false 1/5 of the time.
5. ### A coincidence isn't that unlikely?

Gambler's Fallacy
6. ### A coincidence isn't that unlikely?

The Gambler's Fallacy is a trick of memory, where the observer considers what has been observed but doesn't remember what hasn't taken place.
7. ### Question Regarding Standard Deviation of Rate Vs. Time

Mean for the rate in ml/s wasn't calculated in the original, so I madea copy and added it (blue outlined cells) I also agree the time to complete the fill operation is a better measure. The average speed in ml/sec varies considerably between pumps, and so a small variance in the smallest...
8. ### simple count - type of data

Let's say I'm a test subject, and I recall 15 words. That information alone isn't very informative until we also include the fact there are 50 words. Then we have a proportion: 15 out of 50 words = 15/50 = 3/10 = 30% of the total words.
9. ### An investor is considering funding of a new video game.

Confidence Level: 90% Margin of Error: 5% According to this sample size calculator, the ideal sample size is 271 for very large population, the first answer listed in post #4
10. ### Help with experience-sampling data analysis plan and multilevel linear modelling

Standard error solves problems that standard deviation alone can't. Standard deviation -- average distance away from average -- is good for some problems, but doesn't have anything to say about sample size. Whereas standard error takes into account the sample size; it's still standard...
11. ### Help with experience-sampling data analysis plan and multilevel linear modelling

The problem you're referring to is standard error = (standard deviation) / Sqrt(sample size), used for z-score = (observation - mean)/(standard error) that measures how outstanding an individual is relative to the sample average. As the sample size goes up the standard error goes down, and so...
12. ### Help with experience-sampling data analysis plan and multilevel linear modelling

Example data, with polynomial trend line for x starting attitude = x^0 = 0.875 velocity = x^1 = 0.196x rate of change (acceleration) = x^2 = 0.161x^2
13. ### Help with experience-sampling data analysis plan and multilevel linear modelling

So it's a measurement that can change over time, and you're interested in the rate of change, aka acceleration. enjoyment / sessionTime^0 = location enjoyment / sessionTime^1 = velocity enjoyment / sessionTime^2 = acceleration
14. ### Standard deviation of an average of a number of results

The data given isn't normally distributed It's skewed by 0.5395 and so calculations on the area beneath the curve will have to take that into account.
15. ### Help writing hypotheses!

yes, the two standard deviations are part of the denominator. The MATH thing doesn't seem to be translating LaTex.
16. ### Help writing hypotheses!

Statistics Knowledge Portal corellation(x,y) = covariance(x,y) / standard deviation(x) * standard deviation(y)
17. ### Help writing hypotheses!

correlation and p values
18. ### Help writing hypotheses!

There are four possible outcomes to a hypothesis test
19. ### Help writing hypotheses!

That's a decision threshold you must choose, typically selected as 0.05 For example:
20. ### Help writing hypotheses!

Two hypotheses, stated as the opinion hypothesis vs it's alternative: H1: There is a positive correlation between FDS and SAS H0: There isn't a positive correlation between FDS and SAS H1: There isn't a correlation between FDS and STAI H0: There is a correlation between FDS and STAI The p...