In an analysis of daily soil evaporation (EVAP), Freund (1979) identified the following predictor variables:
MAXAT = Maximum daily air temperature
MINAT = Minimum daily air temperature
AVAT = Integrated area under the daily air temperature curve (i.e., a measure of average air temperature)
MAXST = Maximum daily soil temperature
MINST = Minimum daily soil temperature
AVST = Integrated area under the daily soil temperature curve
MAXH = Maximum daily relative humidity
MINH = Minimum daily relative humidity
AVH = Integrated area under the daily relative humidity curve
WIND = Total wind, measured in miles per day
In addition, Freund provided the following overall ANOVA table and significance tests about the regression coefficients.

a. Compute R2, and provide a test of significance. Use α = .01.
b. Compute R2j for each predictor.
c. Which, if any, variables are implicated as possibly inducing collinearity?
d. Freund (1979) noted that "some of the coefficients have 'wrong' signs." Based on what you know about evaporation, explain which coefficients have wrong signs, paying particular attention to those with extreme t-values.

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Source d.f MS Regression Residual 10 35 8,159.35 1.482.76 815.94 42.36 19.27 Total 45 9,642.11 Variable VIF 0.5011 0.3041 0.09219 2.232 0.2049 0.7426 1.110 0.7514 0.88 0.39 0.42 8.828 MAXAT MINAT AVAT MAXST MINST AVST MAXH MINH AVH 0.19 -2.12 0.98 1.54 -3.44 0.97 8.887 22.21 39.29 14.08 52.36 1981 25.38 24.12 -0.5563 0.00892 1.985