Skip to main content
Statistics LibreTexts

11.3: Biometrics Lab #3

  • Page ID
    2941
  • \( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)\(\newcommand{\AA}{\unicode[.8,0]{x212B}}\)

    Name: ______________________________________________________

    You are studying the growth of a hybrid species of Alaskan pine in three levels of soil moisture (wet, moderate, and dry) over a period of 30 days (0, 5, 10, 20, and 30). You want to determine if this species grows differently over time given different starting levels of soil moisture. Use the given data to test this claim (α = 0.05). If the interaction is significant, at what point does the difference in growth between the levels of soil moisture over time become significant? Use the factor plot and the Grouping information to specifically identify the difference in your conclusion.

    Moisture

    Days

    Growth

    Moisture

    Days

    Growth

    Moisture

    Days

    Growth

    Dry

    0

    7.78

    Moderate

    0

    10.926

    Wet

    0

    8.116

    Dry

    0

    8.09

    Moderate

    0

    9.162

    Wet

    0

    10.473

    Dry

    0

    7.27

    Moderate

    0

    7.83

    Wet

    0

    8.654

    Dry

    0

    11.35

    Moderate

    0

    8.604

    Wet

    0

    6.901

    Dry

    0

    11.94

    Moderate

    0

    9.324

    Wet

    0

    7.565

    Dry

    0

    10.89

    Moderate

    0

    6.462

    Wet

    0

    9.169

    Dry

    5

    7.152

    Moderate

    5

    8.456

    Wet

    5

    10.039

    Dry

    5

    9.117

    Moderate

    5

    11.012

    Wet

    5

    9.994

    Dry

    5

    7.671

    Moderate

    5

    7.541

    Wet

    5

    8.045

    Dry

    5

    10.823

    Moderate

    5

    9.482

    Wet

    5

    9.445

    Dry

    5

    12.309

    Moderate

    5

    9.473

    Wet

    5

    8.024

    Dry

    5

    9.756

    Moderate

    5

    10.2

    Wet

    5

    7.783

    Dry

    10

    9.096

    Moderate

    10

    8.582

    Wet

    10

    7.679

    Dry

    10

    5.864

    Moderate

    10

    9.934

    Wet

    10

    11.671

    Dry

    10

    9.445

    Moderate

    10

    9.279

    Wet

    10

    10.567

    Dry

    10

    7.136

    Moderate

    10

    6.651

    Wet

    10

    9.66

    Dry

    10

    6.869

    Moderate

    10

    10.546

    Wet

    10

    7.646

    Dry

    10

    8.716

    Moderate

    10

    7.927

    Wet

    10

    8.953

    Dry

    20

    4.716

    Moderate

    20

    2.903

    Wet

    20

    7.368

    Dry

    20

    3.528

    Moderate

    20

    4.91

    Wet

    20

    6.539

    Dry

    20

    4.964

    Moderate

    20

    4.998

    Wet

    20

    7.034

    Dry

    20

    5.004

    Moderate

    20

    4.954

    Wet

    20

    7.258

    Dry

    20

    3.824

    Moderate

    20

    3.279

    Wet

    20

    6.309

    Dry

    20

    4.356

    Moderate

    20

    3.528

    Wet

    20

    7.223

    Dry

    30

    1.053

    Moderate

    30

    0.748

    Wet

    30

    4.909

    Dry

    30

    1.287

    Moderate

    30

    0.997

    Wet

    30

    5.891

    Dry

    30

    1.11

    Moderate

    30

    0.7

    Wet

    30

    4.223

    Dry

    30

    0.832

    Moderate

    30

    1.018

    Wet

    30

    3.997

    Dry

    30

    1.082

    Moderate

    30

    1.007

    Wet

    30

    2.616

    Dry

    30

    1.095

    Moderate

    30

    1.083

    Wet

    30

    3.995

    Open Minitab and enter the data into a spreadsheet. Select STAT>ANOVA>General Linear Model.

    Click in the Response box and select GROWTH for the Response box, and enter MOISTURE, DAYS, and MOISTURE*DAYS (interaction term) in the Model box, as shown.

    Image39227.PNG

    Under OPTIONS, select “Adjusted (Type III)” under Sums of Squares. Click OK.

    Under COMPARISONS, select “Pairwise comparisons” using “Tukey” method and enter the two main effects and interaction (MOISTURE, DAYS, and MOISTURE*DAYS) in the terms box (click in the box first to select).

    Check the Grouping Information box. Click OK.

    Image39235.PNG

    Under RESULTS, select “Analysis of Variance Table” for Display of Results. Click OK.

    Under FACTOR PLOTS, enter MOISTURE and DAYS in both the main effects and interaction plot box. Click OK. Click OK.

    Is the interaction term significant? __________________

    Write the p-value ________________________________

    Use the third Grouping Information Using Tukey Method (for the interaction) and the Factor plot to determine where the differences are for each treatment.

    Attach a complete conclusion describing the differences in growth for this species over the 30 days for the 3 different levels of soil moisture.


    This page titled 11.3: Biometrics Lab #3 is shared under a CC BY-NC-SA 3.0 license and was authored, remixed, and/or curated by Diane Kiernan (OpenSUNY) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.