search for: sigalit

Hello, How do I sample observations with replacement from a normal distribution with a specific mean and s.d? (I want to see the sample, not only the statistic.) Thank you, Sigalit. [[alternative HTML version deleted]]

...i] <- rnorm(1,mean=18.531,sd=9.499) } v <- data.frame(y, aps, tiss) log_v <- glm(y~., family=binomial, data=v) summary(log_v) I want to do a repetition of this 600 times (I want to have 600 logistic models), and see all the coefficients of the covariates aps & tiss. Thanks in advance, Sigalit. [[alternative HTML version deleted]]

...1 2 1 11 2 1 11 2 1 11 2 2 8 3 2 8 3 2 8 3 3 12 2 3 12 2 . . i tried: tapply(icu1$aps_st, icu1$hidclass, function(z) mean(unique(z))) but it's counting every row and not every id. thank you, Sigalit. [[alternative HTML version deleted]]

hello, I have a simple question: I want to compute the average of 6 variables, my data looks like this: t0 t1 t2 t3 t4 t5 1 32 34 36 40 38 40 2 35 37 38 36 33 39 . . . I want the mean of t0-t5 for each row (observation). thank you, sigalit. [[alternative HTML version deleted]]

...2 && age<32) age1==1 if (age>=32 && age<52) age1==2 if (age>=52 && age<72) age1==3 if (age>=72 && age<100) age1==4 but I get the results only for the first observation. how can I apply this condition to all observations? Thanks in advance, Sigalit. [[alternative HTML version deleted]]

...xp(-0.834+0.002*x[i]+0.023 +z[i])) x and z generated from normal distribution. I get 300 different probabilities And I want to generate variables from bernulli distribution with P for every observation: T[i]<-rbinom(1,1,p[i]) But i get missing values for T. What I'm doing wrong? Thank you, Sigalit. [[alternative HTML version deleted]]

...0 warnings: the condition has length > 1 and only the first element will be used in: if (dept == "icu") pdeti == 0.95 the condition has length > 1 and only the first element will be used in: if (dept == "reg") pdetr == 0.8 I would appreciate any suggestions, thank you, Sigalit. [[alternative HTML version deleted]]

...omial,data=dat1) summary(log_u) Estimate Std. Error z value Pr(>|z|) (Intercept) -0.54247 0.24658 -2.200 0.0278 * unit1 -0.13052 0.22861 -0.571 0.5680 aps 0.03098 0.01433 2.162 0.0306 * tiss0 0.02522 0.01101 2.291 0.0219 * Thank you, Sigalit. [[alternative HTML version deleted]]

...binom(1, 1, .6) + x2[j] <- rbinom(1, 1, .8) + y2[j] <- z2[j]*x2[j] + } > mean(y2) [1] 0.515 > and this I want to simulate 200 time, in order to see the distribution of y1 and the distribution of y2. How can I repeat it and see all the results? (all the 200 means of y1 and y2) Thank you, Sigalit. [[alternative HTML version deleted]]

...data that looks like this: Id var1 var2 var3.. 1 0 1 0 1 0 1 1 2 2 2 2 Not all id's have the same no. of observations. At the first stage I want to count how many people in the survey, how many have 1 in var1, etc. How do I do that? Thank you, Sigalit. [[alternative HTML version deleted]]

...0 0 3 0 0 3 0 0 3 0 0 and i want to filter out those obs. that has mort30==1 (mort30 is constant over idn). how can i use "if...else" and filter out those unwanted obs.? I appriciate the help, sigalit. [[alternative HTML version deleted]]

...suming the person is sick, is .95, if he is from group Y its .80. i want to know the joint probability: p(the person has the disease and tested sick)=P(D+,T+). my problem is how to write the conditional prob. Thanks for your help, also reference on this subject (binomial simulation) would be great. Sigalit. [[alternative HTML version deleted]]

hello, I want to do a single Imputation method on binary data set. Is it possible to use imp.cat from CAT package? I have a problem defining "theta" when data is binary. Do you know any references on the subject? Thank you, Sigalit. [[alternative HTML version deleted]]

...z1[i] <- rbinom(1, 1, .6) x1[i] <- rbinom(1, 1, .95) y1[i] <- z1[i]*x1[i] } my question is : how to generate the covariates aps, which can get values between 2-37, and tiss, which can get values between 9-36. I want at the and to get similar results as the expected model. Thank you, Sigalit. [[alternative HTML version deleted]]

Hello, I have a question about "qplot": How can I add another line to the same plot ? (like function "lines" in "plot"). Thank You, Sigalit. [[alternative HTML version deleted]]

Hi, I'm trying to do a double for loop like this: for (k in 1:1000){ for (i in 1:200){ y[i]<-rbinom(1,1,0.8) x1[i]<-ifelse(y[i]==1,rnorm(1,mean=20, sd=2),rnorm(1,mean=16, sd=2.2)) .... } for (j in 1:300){ .... } } Does anyone know a good reference about double loops? Thank you, Sigalit [[alternative HTML version deleted]]

...tion, but for every id I have a different no. of rows (obs.). If I write: table(x$class, x$infec) I don't get the right frequencies because I should count every id once, if id 1 has 20 observations It should count as one. can I use unique func. here? Hope it's clear. thank you, Sigalit. [[alternative HTML version deleted]]

...and 3, to see if there are any age differences, and want to count every id once (not all id numbers have the same number of rows). i tried: with( subset(x1, !duplicated(idn)), t.test(age[class=="1"],age[hidclass=="3"] ) but it didn't work. any suggestions? thank you, sigalit. [[alternative HTML version deleted]]

...ction plotEst like this: plotEst(ests,y = dim(ests)[1]:1, xlab="sensitivity", xtic=x1, xlim=range(xtic)) and got the Error: Error in strsplit(x, as.character(split), as.logical(extended), as.logical(fixed), : non-character argument in strsplit() What am I missing? Thank you, Sigalit. [[alternative HTML version deleted]]

...atrix OR with 3 columns (for OR estimate and lower and upper confidence limits) and 1000 rows OR[k,]<-oddsratio(t)$measure["estimate"]? I tried: "exposure==1" or "measure["estimate"]" and it gives me missing value "NA". I appriciate any help, Sigalit. [[alternative HTML version deleted]]