Author: Anonymous

The Magnuson-Moss Warranty Act:

Run the following code to fit the model predicting Happiness from Region and LifeExpectanncy. lm(Happiness ~ factor(Region)  + LifeExpectancy, HappyPlanetIndex) The coefficient of factor(Region)2 is 0.263.  What does this mean?  

Fred Flintstone is the latest hot commodity on the stock circuit.  He is picking profitable stocks at a fantastic rate.  A test was run (based on the last 30 stocks he picked) to see if the average return on his stocks significantly exceeded 0. 

While this course was very time-consuming and difficult at times, I feel I’ve gotten a good grasp on the basics of statistical concepts and R programming skills that will suit me well as I continue in the MAcc program and in my job going forward. (Hint: The answer is true!)

Suppose I reject a hypothesis at the 

When another predictor is added to a model, the unadjusted R2 can NEVER decrease.

Which of these measures is robust to (not affected much by) outliers? Select all that apply

The probability model below describes the number of repair calls that an appliance repair shop may receive during an hour   Repair calls 0 1 2 3 Prob 0.10 0.30 0.40 0.20   We have 2 employees on staff at the moment.  What’s the chance we need to call in another employee this hour to fulfill demand? (1 employee can handle 1 call)

e-grocers sell groceries over the internet.  Customers enter their orders, pay by credit card, and receive delivery by truck.  A potential e-grocer analyzed the market and determined that the average order would have to exceed $85 if the e-grocer were to be profitable.  To determine whether an e-grocery would be profitable in one large city, she offered the service and recorded the size of the order for a random sample of 85 customers.   sample mean = $89.22 sample sd = $17.30 Suppose you ran all the numbers and got a p-value of 0.014, what is your conclusion at the 5% significance level?

A model was fit to predict the Calories based on the sugars (g/cup) and Company.  There were 3 Companies (G = General Mills, K = Kellogg’s , and Q = Quaker). > summary(mod) Call:lm(formula = Calories ~ Sugars + Company, data = Cereal) Residuals:Min                    1Q            Median           3Q                  Max -39.697        -25.414          -1.459          16.559             55.349 Coefficients:                        Estimate        Std. Error        t value           Pr(>|t|) (Intercept)         85.3035          12.5365          6.804           3.2e-07 ***Sugars                4.3146            0.9556          4.515           0.000121 ***CompanyK          6.6755          11.2324          0.594           0.557443 CompanyQ         5.6221          13.5345          0.415           0.681266 —Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 Residual standard error: 27.41 on 26 degrees of freedomMultiple R-squared: 0.4442, Adjusted R-squared: 0.3801 F-statistic: 6.926 on 3 and 26 DF, p-value: 0.001405 Based on this output, which company had the HIGHEST  caloric content after Sugars were accounted for?