significance

  1. marit-rk

    What test to report?

    Hi everyone, So first let me give some background information on my study. Research question: Are there differences on helpfulness between online vinyl record reviews with the indication of a verified purchase and online vinyl record reviews without this indication? This indication of a...
  2. B

    Calculating Power

    Hi Everyone, I am doing a correlation analysis to see which variables impact the quota achievement of a set of sales reps at my company. I am trying to figure out how significant my results are, but am not sure if I am calculating the statistical power the right way. I'm grouping quota...
  3. A

    p values, alpha, and errors

    I was speaking with a classmate about subject heading for this thread and it made me a bit confused. Here are my thoughts: the way I explain p value: probability of observing effect when, in reality, there is no effect. This translates to probability of data given the null (null=there is no...
  4. M

    Z test: can I use it in this context ?

    Hello all. Nice to meet you. I would like to consult you regarding a problem I'm facing: Imagin you have a dataset containing all of the operating workplaces in a certain city (say, 500 in number). The dataset contains the workplace name, average salary and percentage of workers by race and...
  5. U

    Checking significance of bias.

    In a new design, estimator seems to be biased but efficient than the existing design. Now I want to check whether the bias of the estimator based on new design is significant. The formula of the variance of the estimator based on new design is intractable. How can I check the...
  6. A

    Reporting Dummy Variables and Determining Significance

    Hi all, I was just wondering, how does a person determine the significance of a categorical variable in a hierarchical regression model if one dummy variable is significant and the other is non-significant? So basically, the categorical variable (X) I am examining has three levels, so...
  7. N

    Question regarding RM ANOVA

    Dear readers, I have question about my Repeated measures output. I wanted to check for my hypothesis (whether Dutch, masculinized voices in men were more attractive then foreign, masculinized voices in men for a short-term relationship) a three-way interaction between...
  8. F

    significance test begin of puberty

    Hello, I am running a metaanalysis about the age of girls and boys at the beginning of puberty (Tanner-stages) and it would be great if someone could help me out with two questions about significance tests for mean/median value differences. question 1: In SPSS I have the data of the...
  9. J

    Event Study: T-Stat for Cumulative Abnormal Returns

    I am performing an event study using the market model theory. Rit = αi + βiRmt + εit With Abnormal Returns(AR) ARiτ = Riτ − αi − βiRmτ. So to test the significance of the Cumulative Abnormal Return's(CAR's), one must calculate the variance of the aggregated AR's across firms and then sum...
  10. K

    Lack of homogeneity of Variance in two-way ANOVA

    Hi, I am currently analyzing my data in SPSS. Since I am testing the effect of two independent variables on a dependent one, I was planning on using a two-way independent ANOVA. (I have a between subjects design). IVs: 1. Experimental condition (2 levels) 2. Personality grouping (3...
  11. K

    Stats Help needed for a project!

    Hi Stats Fans, I need your help, as I am stuck with data I collected for a project. I am currently gathering responses about mitigation strategies against fatigue. I am questioning people about what mitigation strategies against fatigue they have experienced as helpful. It is a multiple...
  12. L

    Evaluation of impact over time

    I have 3 groups and their data: incoming customers incoming funds When looking on 2 week resolution, I check the percentage difference and can evaluate the impact on these parameters. If I have 5 weeks, data for each week, I need a better statistic to evaluate the impact on the parameters...
  13. C

    How to show statistical significance of one choice in a 4 choice question?

    Participants are shown a video of two performers. They are then asked to select an option from the following 4 choices: 1. Performer A exhibits emotion. 2. Performer B exhibits emotion. 3. Both performers exhibit emotion. 4. Neither performer exhibits emotion. My responses are about 0%...
  14. P

    Question on Standard Error

    If I need to compute the standard error for a bunch of students' test averages, and there are 20 students, each of whose score is itself an average of 8 tests, will my N for SEM=sdev/SqRt(N) be 20? Or will it be 160? In other words, if my bar graph plots the mean of 20 students' averages, but...
  15. M

    Help with statistical power?

    Hi, I'm doing a study looking at the ability of a test to detect a change in bacterial numbers pre- versus post-treatment [i.e. not treatment effect, but pilot study looking at efficacy of the test used]. I've done a chi-square test and got a significant result (p<0.05). However given that I...
  16. Q

    Beginner questions: Clinical trial

    Hi there! I am a medical student working on my PhD, and I am analyzing some data for a meeting. Since we don't learn much about statistics (at least not here in Germany :D), I have some beginner questions and I would be extremely happy if you could help me. The first question is the most...
  17. H

    Correlation matrix with significance

    Does anyone have a ready-made function or know a way to produce a correlation matrix with asterisks marking significance levels in R?
  18. N

    significance of the difference between two values

    Hello all, I'm working on a skew-normal distribution and would like to know if the difference between 2 values of the data set is significant. It's the distribution of Mutual Information between couples of lemmas (100,000 of them). You can see the distribution on the jpg image. What I...
  19. C

    Author's interpretation of Odds Ratio and Confidence intervals

    Hi all, Having some difficulty understanding the results of this paper I am including in a review. It compares the effects of 3 interventions aimed at preventing HIV on couple's relationships. A multivariate logistic regression is used and effect estimates are given (which we are told are odds...
  20. D

    Simspons Diversity Index

    I have calculated the simpsons diveristy index for three different strata: Understorey (1-D= 0.55), Subcanopy (1-D=0.77), canopy (1-D=0.83) How can I test if there is a significant difference between these? Do I need to? Any help would be greatly appreciated. I have had a play around in...