estimation

问题 Sure you could divide the remaining file size by the current download speed, but if your download speed fluctuates (and it will), this doesn't produce a very nice result. What's a better algorithm for producing smoother countdowns? 回答1: I wrote an algorithm years ago to predict time remaining in a disk imaging and multicasting program that used a moving average with a reset when the current throughput went outside of a predefined range. It would keep things smooth unless something drastic

问题 Sure you could divide the remaining file size by the current download speed, but if your download speed fluctuates (and it will), this doesn't produce a very nice result. What's a better algorithm for producing smoother countdowns? 回答1: I wrote an algorithm years ago to predict time remaining in a disk imaging and multicasting program that used a moving average with a reset when the current throughput went outside of a predefined range. It would keep things smooth unless something drastic

问题 I'm trying to make a parameters estimation on Lotka-Volterra model with Scilab (I am a total neophyte). When I try to run the script, Scilab warns about incoherent subtraction. I guess my problem is the same as in this topic, but the solution there uses a Matlab function. Here is my script: // 1. Create Lotka Volterra function function [dY]=LotkaVolterra(t,X,c,n,m,e) IngestC = c * X(1) * X(2) GrowthP = n * X(1) MortC = m * X(2) dY(1) = GrowthP - IngestC dY(2) = IngestC * e - MortC endfunction

问题 It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center. Closed 7 years ago . I have a J2ME CLDC Blackberry app which I need to port to the Android. Some of the features: client/server communication using HTTPS reading/writing PIMs, files on device memory, SD card listeners on PIMs changes

问题 I use the formula exp(X) as the rate for a markov chain. So the ratio of selecting one link over another is exp(X1)/exp(X2). My problem is that sometimes X is very large, so exp(X) will exceed the range of double . Alternatively: Given an array of X[i], with some X[i] so large that exp(X[i]) overflows the range of double , calculate, for each i, exp(X[i]) / S, where S is the sum of all the exp(X[i]). 回答1: This pseudo-code should work: Let M = the largest X[i]. For each i: Subtract M from X[i]

问题 So you've just been put on the spot by The Boss. You've got 15 minutes to come up with a back of the envelope estimate for the addition of some new feature. Your boss (fortunately) recognizes that you can't provide an accurate estimate in that time so expecting something that is in the right order of magnitude. The question is how do you go about giving a estimate in the time frame that is accurate to an order of magnitude? Note that this is meant to be a quick and dirty estimate, not

问题 Inspired by this xckd cartoon I wondered exactly what is the best mechanism to provide an estimate to the user of a file copy / movement? The alt tag on xkcd reads as follows: They could say "the connection is probably lost," but it's more fun to do naive time-averaging to give you hope that if you wait around for 1,163 hours, it will finally finish. Ignoring the funny, is that really how it's done in Windows? How about other OS? Is there a better way? 回答1: Have a look at my answer to a

问题 I am trying to estimate a simple AR(1) model in R of the form y[t] = alpha + beta * y[t-1] + u[t] with u[t] being normally distributed with mean zero and standard deviation sigma. I have simulated an AR(1) model with alpha = 10 and beta = 0.1 : library(stats) data<-arima.sim(n=1000,list(ar=0.1),mean=10) First check: OLS yields the following results: lm(data~c(NA,data[1:length(data)-1])) Call: lm(formula = data ~ c(NA, data[1:length(data) - 1])) Coefficients: (Intercept) c(NA, data[1:length

问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 2 years ago . I am a PHP developer, and I often have no idea in terms of days--let alone hours--how long something will take me at work. I am often writing new stuff, merging it with old legacy crap. I can tell my boss what week I will likely have something done--and maybe what half of what week--but I how in the world am I

问题 This question was migrated from Cross Validated because it can be answered on Stack Overflow. Migrated 3 years ago . I am relatively new to R, so I apologize if my questions isn't expressed well, or if there is excessive detail. What I'm doing here is taking a naturally occurring gas isotope of C12 and C13 that is produced at a linear rate (P) at respective fractions (F12 and F13) that sums to 1. The two isotopic gases are then consumed at rates k12 for C13 and k13 for C13. I then want to