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Evaluate relative importance of variables in regression using standardized regression coefficients approach in R

We provide effective and economically affordable online training courses for R and Python, click here for more details and course registration ! In linear regression analysis, one may be very interested in relative importance of independent variables, that is, which variable contributes most in explaining the variation of response variable. There are several approaches for this purpose. One of them is standardized regression coefficients, which measure how much change of response variable in standard deviation Read more…

By wilsonzhang746, ago

How to calculate probabilities for Exponential distributions in R

We provide effective and economically affordable online training courses for R and Python, click here for more details and course registration ! Exponential distribution is a continuous distribution that models random time between events (until next event occurs) during a Poisson process, which is a process with constant occurrence rate and independence among each individual event. Exponential distribution has the following probability density function: Where positive parameter β denotes the mean time between events, and Read more…

By wilsonzhang746, ago

How to calculate normal distributions in R

We provide effective and economically affordable online training courses for R and Python, click here for more details and course registration ! Normal distribution is a continuous random variable distribution with bell-shaped probability density curve. It is widely used in statistical data analysis, and the basis for many other distributions as well. The probability density function can be expressed as In which the two parameters μ and σ, are its mean and standard deviation, respectively. Read more…

By wilsonzhang746, ago

How to calculate Continuous Uniform distribution probabilities in R

We provide effective and economically affordable online training courses for R and Python, click here for more details and course registration ! Continuous Uniform distribution is used to model a flat probability existence with a range (A,B). Its probability density can be depicted as The follow figure shows probability density curve for a Continuous Uniform distribution defined with range (1,3). In R programming, we can use following functions in computation of Continuous Uniform distribution. dunif() Read more…

By wilsonzhang746, ago

How to calculate Poisson distribution probabilities in R

We provide effective and economically affordable online training courses for R and Python, click here for more details and course registration ! Poisson distribution is used to model the random number (x) of event occurrence during a Poisson process, which focus on the occurrence of same random events during a fixed time period (t) with a constant occurring rate (lambda). The calculation formula of the probability x can be expressed as: In R programming, function Read more…

By wilsonzhang746, ago

How to calculate Geometric distribution probabilities in R

We provide effective and economically affordable online training courses for R and Python, click here for more details and course registration ! Geometric distribution is to model the random trial number X until a first success, in Bernoulli trial experiments, with constant success rate p. The probability of x can be calculated as Geometric distribution is a special case of Negative Binomial distribution, which models the X trial is the n success trial. R programming Read more…

By wilsonzhang746, ago

How to read csv file using Numpy in Python

We provide affordable online training course(via ZOOM meeting) for Python and R programming at fundamental level, click here for more details. Numpy module has a function genfromtxt() that is used to read tabular data format into an array. The option for the function is the file name in working directory, delimiter and first line as variable name. The following example shows how to read a csv file into an structured array. You can see Numpy Read more…

By wilsonzhang746, ago

How to save and read Numpy array in Python

We provide affordable online training course(via ZOOM meeting) for Python and R programming at fundamental level, click here for more details. When you are doing data analysis with Numpy module in Python, it is not uncommon that the array data information needs to be stored on local driver, then it is possible to read it again later into working session. Numpy provides two functions on this purpose. save() function is used to save an Numpy Read more…

By wilsonzhang746, ago

How to create structured arrays in Python

We provide affordable online training course(via ZOOM meeting) for Python and R programming at fundamental level, click here for more details. We know Numpy arrays are data objects that store same type of data in one object. However, this statement is not strictly correct. Numpy provides also availability to create array that allows different data types in it. This kind of array is called structured array. Let us see an example. We have seen, A1 Read more…

By wilsonzhang746, ago

Broadcasting of Numpy arrays in Python

We provide affordable online training course(via ZOOM meeting) for Python and R programming at fundamental level, click here for more details. If two Numpy arrays may having different shapes take operations, e.g. addition or subtraction, and their shapes are compatible for such operation. This is called broadcasting. The prerequisite of broadcasting is that either two arrays have the same shapes, or at least one axis of an array is 1. In the latter case, this Read more…

By wilsonzhang746, ago