Question

3. You have been asked to find if there is a correlation between the amount of calories per serving in a bowl of cereal versus the amount of sugar (in grams) in the cereal. The following data has been given for examination. Calories Sugar 18 200 23 210 12 170 12 190 37 220 19 175 23 201 22 210 32 210 11 190 11 197 205 29 a. Create a scatterplot of the given data. Be sure you explain your decision on which variable is the predictor and which variable is the response. (10 points) b. Using computer software, calculate the correlation coefficient and interpret what this value implies in relation to the data set. (5 points) C. Create a regression equation that models the data and describe the values of the slope and y-intercept with the data set. (5 points) d. Predict if a box of cereal has 25 grams of sugar per serving how many calories it will contain. (5 points) e. Predict if a box of cereal has 230 calories per serving how much sugar (in grams) it will contain. (5 points) f. Discuss any lurking variables could be relevant to analysis of this data set. (5 points)

Answer 1

250 200 150 Series1 100 50 0 O 10 20 30 40

On the X axis, is sugar (in grams) and Y axis is calories.

here, the predictor is sugar and the response variable is calories.

2.

	x	y
	18	200
	23	210
	12	170
	12	190
	37	220
	19	175
	23	201
	22	210
	32	210
	11	190
	11	197
	29	205
correlation	0.734
slope	1.258
intercept	172.073

The correlation coefficient is found using Excel, using the command =correl(knownXs,knownYs) and is found out to be 0.734 which indicates a positive relationship among the variables. that is, sugar consumed and calories are positively correlated.

3. The regression equation is given by Y = a+bX, where

Y is the estimated calories

a is the intercept found in excel using =intercept(knownYs,knownXs)=172.073

b is the slope found using =slope(knownYs,knownXs) = 1.258

Thus, Y = 172.073 + 1.258X

4. If X = 25, Y =172.073 + 1.258*25 = 203.523. It will contain 203.5 calories.

Only 4 subparts can be answered in a multiple part question. Please give the remaining as another question.

Thank you!