Loblolly Analytic App

X. SHEN
October 25 2014


Developing Data Product
Data Science Specialization

Overview

Loblolly Analytic App is an analytical shiny application that summarizes the Loblolly pine tree data and fits a nonlinear model for different seed sources. This App allows the users to download a plot with the fitted curve based on the selected seed source.

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Data & Descriptive Statistics

The Loblolly data frame has 84 rows and 3 columns of records of the growth of Loblolly pine trees.

  • Height: a numeric vector of tree heights (ft).
  • Age: a numeric vector of tree ages (yr).
  • Seed: an ordered factor indicating the seed source for the tree.
summary(Loblolly)

     height           age            Seed   
 Min.   : 3.46   Min.   : 3.0   329    : 6  
 1st Qu.:10.47   1st Qu.: 5.0   327    : 6  
 Median :34.00   Median :12.5   325    : 6  
 Mean   :32.36   Mean   :13.0   307    : 6  
 3rd Qu.:51.36   3rd Qu.:20.0   331    : 6  
 Max.   :64.10   Max.   :25.0   311    : 6  
                                (Other):48

Fitted Nonlinear Model (seed=305)


Formula: height ~ SSasymp(age, Asym, R0, lrc)

Parameters:
     Estimate Std. Error t value Pr(>|t|)    
Asym   99.172      6.724    14.8  0.00068 ***
R0     -9.917      1.304    -7.6  0.00472 ** 
lrc    -3.085      0.112   -27.6  0.00010 ***
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

Residual standard error: 0.773 on 3 degrees of freedom

Number of iterations to convergence: 0 
Achieved convergence tolerance: 4.98e-07

Plot Fitted Nonlinear Curve (seed=305)

plot of chunk plot