## Combining two plots...

Hello,

does anyone know a way to combine two plots in one where one is created with ScatterPlot3D (Package:Statistics) and the other one with plot3D (Package:plots)?

Normally you would write something like this:

but that only works if the plots are from the same package...

## Fit a Graph with 3 points...

I'm wondering why the fit routine gives weird results, when telling him to fit

with(Statistics):

X:=Vector[column](3, {1 = 616.3096, 2 = 616.3248, 3 = 616.3342}, datatype = sfloat, storage = rectangular, order = Fortran_order, shape = []);

Y:=Vector[column](3, {1 = 99590., 2 = 127564., 3 = 144223.}, datatype = sfloat, storage = rectangular, order = Fortran_order, shape = []);

g:=Fit(a+b*x+c*x^2,X,Y,x)

It's telling me: Warning, model is not of full rank

If I calculate the coefficients the direct way (well the fit should be exact,because we only have 3 values and 3 parameters) I get:

M:=Matrix(3, 3, {(1, 1) = 1, (1, 2) = 616.3096, (1, 3) = 379837.52305216, (2, 1) = 1, (2, 2) = 616.3248, (2, 3) = 379856.25909504, (3, 1) = 1, (3, 2) = 616.3342, (3, 3) = 379867.84608964}, datatype = anything, storage = rectangular, order = Fortran_order, shape = []);
V:=Vector[column](3, {1 = 99590, 2 = 127564, 3 = 144223}, datatype = anything, storage = rectangular, order = Fortran_order, shape = []);
with(LinearAlgebra):
C:=MatrixVectorMultiply(M^-1,V)

Hi all.

I want to know how do I declare symbol in maple. Say y=2x+b, I want maple to treat this y as a function of x with b as a constant (or symbol). How should I do that?

More specificaly, I am trying to ask maple to do some calculation for me. and it returns me "Fail". So I am suspecting that maple didn't take other letters as symbol. Here is my code:

with(Statistics); h := RandomVariable(Exponential(H)); simplify(PDF(h, t))

with(Statistics); g := RandomVariable(Exponential(G)); simplify(PDF(g, t))

constants := constants, Ps Pr

PDF(Ps*g*h/(Pr*g+2), t)

but maple return:

Fail

## How to type "bar over Y," the average symbol in Ma...

Hello, I am a student typing up my homework assignments with maple, and I am takinng Inferential Statistics.  I can't figure out how to make the bar over a variable, so I can note the average.  It is just a line over a letter.  Kind of when notating a vector without the arrow.  It would be very helpful because I can't figure out how to make that symbol, it is not listed on the symbols list on the left side.

Thanks!

## Create Dendrogram for Cluster Analysis in Statisti...

Hi all,

I tried to used some statistical methods to analyze the data in maple and encountered some problems.

I wanted to perform a cluster analysis to quantify differences among individual samples and hoped to create the dendrogram like this:

For example, each sample is assigned to a cluster and there are about 4 main clusters plus additional outliers in this case through the dendrogram method.

But I didn't find any related command to create this kind of graph. How to realize this analysis in Maple?

I'd appreciate any help on this topic. Thank a lot.

## Statistics question ...

I have a statistics task that is very complicated to me, and I would really appretiate some help!

I believe that I have completed task a, but task b and c seems to be too hard for me to grasp.

Here is a presentation of the task text:

xi 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
yi 12.3 12.8 16.8 17.9 20.5 22.7 24.9 27.5 26.9 29.4 30.3 34.2 36.4 36.7 41.1

Assume that the data represents independent realizations of a "linearlnormal" model.

Yi = α + β xi + ei i = 1..15,

where ei˜N(0,σ), where sigma is unknown.

(a) create a scatterplot of the data {f(xi,yi)}15 ; i=1
Then calculate the empiric correlation coefficient.

(b) Find the minimum least square estimate for α & β.

(c) Create a 95% confidence interval for the parameter β. What does this confidence interval express?

Is there anyone out there who are able to help me with some maplecode?

Soeta

## Plotting a data set using ...

Hi folks,

from an experiment I gathered some data which I am now trying to display in a nice plot. The data contains x and y values (as well as errors for the y values, that are not part of my problem however). It appears that 'ErrorPlot' (Statistics package) seems to be the tool to use in my case, however I am not able to figure out how to assign the x values to the y values. By default Maple uses positive integers as the x values for any input set. Let's say my data is

x:=[1,5,8,9,10,15]

y:=[4,3,2,8,9,9] (with errors yr:=[0.5,0.5,0.5,0.5,0.5,0.5])

then, now matter how I try, the x values assigned are always 1,2,3,.. . Doing sth. like

> ErrorPlot([x,y]);

displays the sets of x and y each being assigned to integers rather than plotting y over x.
Can anybody help me with this issue?

tl;dr

How do I assign individual x values for my set of data using 'ErrorPlot' (from the Statistics pkg)?

Thank you very much!

Greets,
mulo

## histogram plot error...

Hi,

When I try the example of a histogram plot from the help system (under Statistics, Histogram), I get an error.

The example (entered in document mode) and error follow below.  Can someone please shed light on this?

`with Statistics; with(plots):N := RandomVariable(Normal(0, 1)):A := Sample(N, 1000):P := DensityPlot(Normal(0, 1), color = "Niagara Red"):Q := Histogram(A, averageshifted = 4, style = polygon, color = "LightSlateGrey"):`

## Density Plot Not as expected...

To plot the density function of the continuous uniform distribution on [-1,1], my initial attempt was:

plot(Statistics:-PDF(Statistics:-RandomVariable(Uniform(-1,1)),x), x = -1.1 .. 1.1);

See plot below.

But I wanted something more like the wikipedia image (without the labels, naturally):

See plot below.

In words, I expected a horizontal line on the left of x=-1 and on the right of x=1 (at y=0), and I expected no vertical line at the x=-1 and x=1 points ...

## AutoCorrelation Maple vs MatLab...

what is the difference between the autocorrelation function of Maple and MatLab function xcorr?

> N := 1024;
> f1 := 1;
> FS := 200;
> n := Vector([`\$`(0 .. N-1)]);
> x := evalf(`~`[sin](2*Pi*f1*n/FS));
> t := Vector([`\$`(1 .. N)]/FS);
> plot(t, x, axes = box, gridlines, color = blue, title = "Sinwave of frequency 1000Hz [FS=8000Hz]", labels = ["Time, [s]",

"Amplitude"], labeldirections = ["horizontal", "vertical"]);

## Compute power of tests...

Is it possible to display on a same graph the error of type I and type II error given n, alpha and beta?

PowerTest

applet.zip

Gracias

## problems plotting growth models...

hello

This is what I have written out in Maple, and I have been trying to plot into a graph, but am having no luck at all.  Do you have any advice for what my next step should be. I'm using a simplified version of Brain and Cousens model.

> restart;

> with(plots);

> with(Statistics);

y := (x) -> (d+fx)/(1+h*x^b) , x > 0

b := 2; d := 1; h := 1;

This is the question: Let b = 2, d = 1 and h = 1