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Regression, Correlation and Hypothesis Testing

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Question 55

An operations manager at a data centre is monitoring the relationship between the external ambient temperature (TTT ∘C^\circ\text{C}∘C) and the daily energy consumption of the cooling system (EEE kWh). The following data were recorded over 10 separate days:

Temperature (TTT)18222528303235384042
Energy (EEE)14161819212223252628

[You may use: ∑T=310\sum T = 310∑T=310, STT=564S_{TT} = 564STT​=564, ∑E=212\sum E = 212∑E=212, ∑E2=4676\sum E^2 = 4676∑E2=4676, STE=319S_{TE} = 319STE​=319]

a.

Calculate SEES_{EE}SEE​.

[2]
b.

Calculate the product moment correlation coefficient (PMCC) for these data.

[2]
c.

Interpret the value of the correlation coefficient in context.

[1]
d.

State, giving a reason, whether or not your value of the correlation coefficient supports the use of a linear regression model for these data.

[1]
e.

Find the equation of the regression line of EEE on TTT, in the form E=a+bTE = a + bTE=a+bT.

[3]
f.

The manager notes that the forecast for the following day is 36 ∘C^\circ\text{C}∘C.

(i) Use your regression line to estimate the energy consumption for this forecasted temperature. (ii) Comment, giving a reason, on the reliability of your estimate.

[2]

Regression, Correlation and Hypothesis Testing Questions

  1. A Level
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