sure is easy in minitab ... one can draw a very nice curve (it's easy but,
hard to post here) but, to make a distribution easy for viewing we can
MTB > rand 100000 c1; <<< generated 100000 values from
SUBC> chis 4. <<< a chi square distribution with 4 degrees of freedom
MTB > dotp c1
Dotplot: C1
Each dot represents up to 778 points
.
.::.
:::::
.::::::.
:::::::::
::::::::::.
:::::::::::::.
::::::::::::::::::......................... . .
+---------+---------+---------+---------+---------+-------C1
0.0 6.0 12.0 18.0 24.0 30.0
MTB > desc c1
Descriptive Statistics: C1
Variable N Mean Median TrMean StDev SE Mean
C1 100000 4.0123 3.3729 3.7727 2.8350 0.0090
Variable Minimum Maximum Q1 Q3
C1 0.0080 29.4143 1.9236 5.4110
not quite as fancy as the professional graph but, will do in a pinch
At 06:27 PM 2/21/02 -0800, David Heiser wrote:
>-----Original Message-----
>From: [EMAIL PROTECTED]
>[mailto:[EMAIL PROTECTED]]On Behalf Of Ronny Richardson
>Sent: Wednesday, February 20, 2002 7:29 PM
>To: [EMAIL PROTECTED]
>Subject: Chi-square chart in Excel
>
>
>Can anyone tell me how to produce a chart of the chi-square distribution in
>Excel? (I know how to find chi-square values but not how to turn those into
>a chart of the chi-square curve.)
>
>
>Ronny Richardson
>---------------------------------------------------------------------------
>Excel does not have a function that gives the Chi-Square density
>
>The following might be helpful regarding future graphs. It is a fraction of
>a larger "package" I am preparing. It is awkward to present it in .txt
>format.
>
>
>DISTRIBUTION DENSITY CUMMULATIVE I NVERSE
>Beta BETADIST
>BETAINV
>Binomial BINOMST CRITBINOM
>Chi-Square CHIDIST CHINV
>Exponential EXPONDIST EXPONDIST
>F FDIST FINV
>Gamma GAMMADIST GAMMADIST
>GAMMAINV
>Hyper geometric HYPGEOMDIST
>Log Normal LOGNORMDIST LOGINV
>Negative Binomial NEGBINOMDIST
>Normal(with parameters) NORMDIST NORMDIST NORMINV
>Normal (z
>values) NORMSDIST NORMSINV
>Poisson POISSON
>t TDIST TINV
>Weibull WEIBULL
>
>You have to build a column (say B) of X values.
>
>Build an expression for column C calculating the Chi-Square density, given
>the x value in col B and the df value in A1.
>
>It would be "=exp(($A$1/2)*LN(2) + GAMMALN($A$1/2) + (($A$1/2)-1)*LN(B1) -
>B1/2)" without the quotes.
>You can equation-drag this cell down column C for each X value.
>
>Now build a smoothed scatter plot graph as series 1 with the X value column
>B and the Y value as column C.
>
>DAHeiser
>
>
>
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