#HISTOGRAM IN EXCEL 2016 ONLINE HOW TO#

Note: the theoretical mean is given by kp, and the variance by kp(p+1). The closer these statistics obtained from the data and from the parameters, the better the fit. The first result of interest for us is the value of the k and p parameters of the negative binomial distribution (fitted using the maximum likelihood method), and the estimates of the sample and theoretical mean, variance, skewness and kurtosis. Interpreting the results of a distribution fitting analysis Select the following options in the tab Charts. In the Options tab, activate the Goodness of Chi-square tests, which is necessary to test our assumption. The one that is adapted to our case is the second one. XLSTAT offers two different formulations of the negative binomial distribution. We let XLSTAT estimate the parameters of the negative binomial distribution function. In the General tab, select column B in the Data field.

Select the data on the Excel sheet named Data. The Distribution fitting dialog box then appears. Select the XLSTAT / Modeling data / Distribution fitting command (see below). Setting up the dialog box to fit a distribution

#HISTOGRAM IN EXCEL 2016 ONLINE HOW TO#

The following video shows you how to reproduce those results.Р”Р„s we are satisfied by this result, we can now use the distribution fitting tool to test if the sample follows a negative binomial distribution. The computations begin once you have clicked on the OK button, and the new histogram appears (see sheet 'Histogram1'). In order to verify if the frequencies of the new classes are greater than 5 and decrease regularly, we create a new histogram, specifying this time the bounds of the intervals in the tab Options. For this reason, we create a list of bounds that seems coherent with our problem: 0,1,2,3,4,5,10,15,20,40. Since we want to test the fit between the negative binomial distribution function and the sample (the Chi-square test requires that there is are least 5 data in a class), and because of the uncertain precision of the counts of the bacteria, it seems necessary to group the counts into larger classes. Creating a histogram specifying the bounds of the intervals In one sample, over 36 colonies have been counted.

We also notice that the frequency decreases quickly. That is, in more than one sample out of five, no bacteria has been found. On the histogram we can see that the most frequent value is 0, which represents over 20% of the data. The histogram is displayed on the sheet Histogram below the Summary Statistics table and followed by a table where the statistics of the histogram are available. The results will then be displayed on a new sheet.

The Sample labels option is left activated because the first row of the data selection contains the name of the sample.Р”В¬lick on the OK button to launch the computations. We activate the discrete option because the counts are discrete values. In the general tab, select column B in the Data field. Once XLSTAT is open, select the XLSTAT / Visualizing data / Histograms command (see below). Setting up the dialog box to create a histogram In the Bact-Data column you will find the counts for the 200 samples. The number of colonies has been counted after 72 hours of incubation. The data correspond to an experiment where 200 samples of water from a river were cultured on medium with nutrients to determine the presence or absence of bacterial contamination with Escherichia coli. Data to create a histogram and fit a distribution This distribution is often used to represent the aggregation/dispersion phenomenon of bacteria in water environments. The purpose of this tutorial is to generate a histogram and test if a sample follows a negative binomial distribution using the XLSTAT distribution fitting tool in Excel.

Histogram in excel 2016 online