# variables

1. ### Is there a difference between z-score and effect size?

I just started teaching statistics to myself (I never had it in school but will need it when I start University). I have problems with z-scores and effect size. I think that you use a z-score if you want to know how a score compares to the mean or standard derivation. And you use the effect...
2. ### How to "stack" variables

Say that I have performed a survey in which I have asked subjects to use a three-item, five-point Likert scale to rate three scenarios. My data would be formatted to look something like this (Sx indicates scenario, Ix indicates item): Subject S1_I1 S1_I2 S1_I3 S2_I1 S2_I2 S2_I3 S3_I1 S3_I2...
3. ### Unique combination of variables

Hi guys I have 15000 observations across 7 variables. I need some help with the code to generate all possible unique combinations of variables. e.g. if I had 2 variables and 4 observations per variables V1=a,b,c,d V2=1,2,3,4 Then, combinations = a 1, a 2, a 3, a 4,b 1, b 2, b 3, b 4, c 1, c...
4. ### SPSS Graph of two variables

Hi, I'm new to SPSS - so sorry if this question is rather stupid... I have several variables that have the same values (all measure on a Likert 7 scale). How can I create a line graph with each line representing one variable, the x-axis representing the value (i.e. 'do not agree at all'...
5. ### What analysis to use

Dear all, I have 3 independent variables (1-5 Likert Scale) questions and I want to check how well these three can predict/explain my DV (1-5 Likert scale) The three independent variables are: 1. Quality of information 2. Accessibility of staff 3. Quality of technical advice My DV...

Hi! Please, please help! have a paper due in 8 days! and can't figure out how to work this out in SPSS. I am looking at whehter there is a relationship between unintended pregnancies (defined as the summation of mistimed and unwanted pregnancies) and experience with intimate partner violence...
7. ### Basic hypothesis question - variables

Hello, I am new to statistics so please excuse my ignorance. My question relates to a hypothesis which I would like to test. I know that hypotheses need and independent and dependent variable. My question is: Can there be two independent variables in a hypothesis. Example...
8. ### SPSS Help with Variable

Hello, I'm writing a thesis for an MSW program, and while my program has been interesting, it has completely neglected any information on how to actually analyze data in SPSS or what statistical analysis to use. At the risk of sounding like an idiot, please help me! Basically, I have...
9. ### 2 independent categorical variables. What test do I use?

Sorry if this has been asked before, if it has I couldn't find it. Also excuse me if I mix up terms, I'm a bit of a novice. My experiment had two categorical independent variables. 1.)The feeding history of the fly (protein fed or sugar fed) 2.)The type of substrate tested for preference...
10. ### Grouping educational level in different variables

hi there! I'm trying to apply a regression model based on the Human Capital Theory. Besides other independent variables, I have grouped the educational level (in years) in 4 distinct variables, in the following way: E1: variable that assumes values 1, 2, 3 or 4 in the case of the...

4. The following table lists 3 personnel records of a company. Staff ID Birthday Monthly Salary A123 4 March 1989 8,600 A037 23 June 1957 21,450 M015 19 September 1976 17,500 Staff id number has the format...
12. ### Linear Regression - variable issues!

Hi there, I am trying to run a linear regression on some data to investigate a mediating relationship. There are three variables: whether or not training was provided (IV), social skills (DV) and hours of self-study (MediatorV). My IV has two levels represented as 0 (control) and 1 (training...
13. ### "Is there a sig. difference in amount of subunits between 2 groups according to age"

Hello! I think I've said it all in the title. I need to run right statistics to answer my question. I guess I have 2 independent variables (age in days and group code (1=experimental group; 2=control group)) and 1 dependent (amount of subunits), right? O.K. so I found out, that I can't do a...
14. ### If a potential third variable is a function of two others, is necessarily redundant?

Say I am using regression analysis to try and estimate the assembly time for widgets (which can be produced in various sizes) given some possible independent variables: Width Height Quantity of pieces (different sizes used as components) Did the American League win the World Series etc...
15. ### Random variables and probability distributions

The question i need help to is below: Laboratory tests on a large shipment [several thousands] of radios revealed that 6.5% are defective. On arrival of the shipment at the local distributor, 30 of the radios were randomly selected for a promotion. (a) Define the random variable for...
16. ### Dummy Variables - How do I indicate to change graph color?

I'm extremely new to SAS and still find it pretty intimidating. I'm trying to graph the relationship between fish eggs and the age of the fish. I also have a dummy variable, month. I've successfully plotted the simple linear regression model without the month being included, but I wish...
17. ### Trying to find the correlation for 2 variable when controlling for 2 other variables

I summed up some of the info we are already provided: N=50 Having job and exam performance--- r= -.3 Having job and and Studying--- r= -.4 Studying and exam scores--- r= .70 We are suppose to calculate the correlation between having a job and exam scores while controlling for the...
18. ### Multiple Regression with Discrete and Continuous data in Excel

Hi, I've got lots of rows of data in Excel (around 3,500), and multiple variables. 1 of my variables is continuous (company revenues) 1 of my variables is a Yes or No 3 of my variables have a few (3-5) discrete options The output is money (continuous). I'm trying to use Excel to find...
19. ### Variables that are Both Predictors and Response Variables

I have been reading about variable/feature selection algorithms. All of the algorithms that I have seen presume that there is a clear distinction between predictive and response variables. However, I have some variables that could be either. I would like to analyze a large set of variables...
20. ### GLMM Predictor variables

Hi all, I have a quick question regarding predictor variables in a GLMM analysis, a subject I am new to. I am running a study investigating multi-modal communication in primates. specifically, primate gestures that accompany vocalizations. I have measured the call rate, call duration...