Question

The percentage of variation in the amount of steam (Y in pounds) in production process of a chemical plan that can be attributed by the ambient temperature (X in degree Celsius) has been found to be 79 %. From the least-squares regression analysis, it was also found that for a 1-degree Celsius increase in ambient temperature the consumption of steam increased by about 16.75 pounds. Consider the following statements:

I. If the ambient temperature were measured in Fahrenheit, the value of the correlation would not change.

II. The more the ambient temperature, the higher the steam.

III. Correlation coefficient value is 0.888.

Which of the above statements is/are true?

Select one:

a. II only

b. II and III only

c. All statements are correct

d. I only

e. I and III only

Answer 1

Given that R square = 79% or 79/100 = 0.79

Correlation coefficient r = . So, option III is correct.

Slope coefficient is 16.75 , this means that  for a 1-degree Celsius increase in ambient temperature the consumption of steam increased by about 16.75 pounds. So, increase in temperature will increase the consumption of steam. Option II is also correct.

yes, it is correct that if the ambient temperature were measured in Fahrenheit, the value of the correlation would not change. This is because the slope and standard deviations for x and y remains same even after chaning to Fahrenheit. Therefore, option I is also correct.

Answer is

c. All statements are correct