Was I just making that stuff up? b) The coefficient of determination is 0.1225. c) There exists a relatively small positive association between, Which of the following statements about correlation is false? This make sense. (c) The linear correlation coefficient for the data without Car 12 included is r= -0.968. The following data represent the weight of various domestic cars and their gas mileage in the city for the 2005 model year. did not change. (a) Determine which variable is the likely explanatory variable and which is the likely response variable. 0000367230 00000 n Correct Answer (a) The slope is 1.109. Question 9 30 seconds Q. AMab Briefly explain when an observed correlation might represent a true relationship between variables and why. b. Complete parts (a) through (f) below. For example, the average gas mileage of Ford Focus 1.6 produced between 1998 and 2005 amounts to 7.61/100 km. Compare the results of parts (a) and (b) to the scatter diagram and linear correlation coefficient without Car 12 included. Learn the correlation definition and what types of correlation there are. Redraw the scatter diagram with Car 13 included. No, because a hybrid gas and . You must be logged in to perform that action. c. The error term has a zero mean. explanatory variable response variable b) Draw a scatter diagram . 0000403945 00000 n State the hypotheses, degrees of freedom, and critical value for your test. . 12.28 Are the variables cross-sectional data or time-series data? An engineer wanted to determine how the weight of a car affects gas mileage. News, Reviews, Photos, Videos delivered straight to your in-box. for Cubic Capacity. The explanatory variable is the weight and the response variable is the miles per gallon. Suppose that we add Car 12 to the original data. c. there has been a measurement error. df SS MS F Significance F per gallon in the city. No, there is no correlation. 0000087040 00000 n a. Coefficient of determination is -1.0. b. Coefficient of correlation is 0.0. c. Sum of squares for error is 0.0. d. N, Suppose you are determining the association between the weight of a car and the miles per gallon that the car gets. Step 2/2. In this case, I went for the "curb weight" and converted to kilograms. Car 12 weighs 3,305 pounds and gets 19 miles per gallon. A correlation coefficient between two variables is 0.50, and this correlation is statistically significant at p < 0.01. So the question boils down to which engine has more friction per cycle, and which car has more weight to carry around. An engineer wanted to determine how the weight of a car affects gas mileage. Write your answers to exercises 12.28 through 12.43 (or those assigned by your instructor) in a concise report, labeling your answers to each question. (a) Determine which variable is the likely explanatory variable and which is the likely response variable. endstream endobj startxref What does this say about the usefulness of the regression equation? Final answer. B. e)Suppose an editor for the publication wishes to predict the highway mileage of vehicles with a curb weight of 6,000 pounds. Scientists say a mild Covid infection increased immune benefits from a later flu vaccine, but with a biological twist. Click here to view the table of critical values of the correlation coefficient. 0000383019 00000 n 0 Weight (pounds), x Miles per Gallon, y 3808 16 3801 15 2710 24 3631. Do the same for a car with city mileage 28 mpg. What fraction of the variability in fuel economy is accounted for by the engine size? Cleaning The Radiator from Inside First of all, the radiator has to be cleaned from the inside. Using the following information: What is the correlation coefficient? Conclusion: Cigarettes cause the pulse rate to increase. 0000088125 00000 n For every pound added to the weight of the car, gas mileage in the city will decrease by mile(s) per gallon, on average. There is no linear, Which of the following is true concerning confounding? HW-GWUY-`d5|d]=sG fq*/~/}Iof{4n3o9cZ2^ZZoy/sT'lXk;|j}{.8 Gy/^cgx~z}@M {l[pT4lD&|l ./{Nq@_P a> =V} A weightless car will get miles per gallon, on average. Which of the following statements regarding the coefficient of correlation is true? Is there a correlation between variable A and B? Select one: a. Acura TSX 23 3,320 Lexus IS 300 18 3,390 Why are the results here reasonable? Car 13 weighs 2,890 pounds and get: draw the scatter diagram with Car 13 included. 12.37 (a) Based on the R2 and ANOVA table for your model, how would you assess the fit? 0000044566 00000 n Complete parts (a) and (b) below. The explanatory variable is the miles per gallon and the response variable is the weight. Statistically, explain what is wrong with this researcher's analysis. The following results were obtained as part of a simple linear correlation analysis: Y = 97.98 - 4.33x; regression sum of squares is equal 2680.27. The table below presents data from the 1975 volume of Motor Trend concerning the gasoline mileage performance and the engine displacement for 15 automobiles Fit a regression model relating mileage per But is it possible that this trend happened by chance? c. The error terms decrease as x values increase. Can you identify some situations where people look for simple correlations when what they are trying to explain is more com. c. Adding the multiplication. 3&1!}+1~m0 !mq#D^Wm'!>avp! B) It is impossible to get a correlation greater than 1. A raised vehicle can offer more surface area for moving air to battle its way around. The correlation is moderate to strong. Which statement does not belong? Your gas consumption depends on a range of factors. Now for a plot. If r = 0, there is no relationship between the two variable at all. ", B. . Transcribed image text: An engineer wanted to determine how the weight of a car affects gas mileage. (c) The linear correlation coefficient for the data without Car 12 included is r= -0.968. For example, the greater the mileage on a car, the lower the price. = .05. Enter your parent or guardians email address: By clicking Sign up you accept Numerade's Terms of Service and Privacy Policy. Mondays massive earthquake has triggered a swarm of aftershocks, which will make a humanitarian disaster even more devastating. (b) The intercept is 4.62 mpg. 0000374679 00000 n If so, can we predict the mileage rating of a car given its weight? [R138'4uQr#?v*6a a. sx = 1.355, sy = 15.300, b = -9.780 a. An engineer wanted to determine how the weight of a car affects gas mileage. has a weight outside the range of the other cars' weights. A positive residual means that the car gets better gas mileage than the model predicts for a car with that much horsepower. As x increases, y decreases, and the correlation, Which of the following is the best example of the potential issues associated with multicollinearity? The answer to that question wasThe 95% confidence interval estimate for the gas mileage for the Cadillac is 20.68 to 23.56 mpg. You must have JavaScript enabled to experience the new Autoblog. Give examples with your response. Complete parts (a) through (d). !1997 F350 XLT 4x4 Crew Cab (4 door) 7.3 Liter V-8 Diesel Powerstroke, Automatic with overdrive, Dana 60 front axle, Weld Racing Wheels and Toyo Open Country Radials (tires and wheels cost $4500) only 66,000 original miles Located in Seattle Washington 98188 1 mile from Seatac AirportI . 0000088713 00000 n The engine may also be used for performance or for better fuel mileage. If you google something like "2009 Pontiac G5 curb weight," you might find several answers that don't agree. b) Calculate a 95% prediction interval for the average highway mileage for cars with a curb weight equal to the weight of the Cadillac after his family is inside. OD. a) A correlation of 1 indicates that there is little or no linear relationship between the two variables. B. Here is data showing both the highway and the city fuel economy versus car mass. b. b. Therefore, a correlational value of 1.09 makes no sense. Think about air drag and stuff. C. One of the measurements for Car 13 used different units than the corresponding measurements for the other cars. (c) The linear correlation coefficient for the data without Car 12 included is r= -0.968. Engines in today's automotive vehicles come in different sizes and number of cylinders depending on the vehicle size and weight or the work the engine is expected to do. The accompanying data represent the weights of various domestic cars and their gas mileages in the city for a certain model year. The correlation coefficient, r = -1, implies a. All rights reserved. Sometimes I do that - but hopefully I was correct. 0000362469 00000 n Sean has a theory that the average weight of an animal has a high correlation with the number of letters in its name. 0000382127 00000 n (a) Draw the scatter diagram with Car 12 included. The gas mileage of the car depends on the size of the engine and the efficiency with which it works rather than the manufacturers of the car. a. 0000089165 00000 n 0000382677 00000 n hb``e``AXX80,,tqq$,d%0h Idt4[ m`e(>W2v11y21d` i'c G&tS,XD&hV3132D231233,!!!AH Zlb !O2l4#x i&?`Nm.#D @ t:L endstream endobj 216 0 obj <>/Filter/FlateDecode/Index[34 119]/Length 27/Size 153/Type/XRef/W[1 1 1]>>stream Chevy Silver1500 14 4,935 Mitsubishi Galant 20 3,285 Compute the linear correlation coefficient between the weight of car and its miles per gallon. 0000382826 00000 n The error terms have constant variance. 0000086067 00000 n (e) Did the sample support your hypothesis about the sign of the slope? The breakthroughs and innovations that we uncover lead to new ways of thinking, new connections, and new industries. 2003-2023 Chegg Inc. All rights reserved. By firing lasers through underground fibers, scientists can detect seismic waves and perhaps improve alertsgiving people precious time to prepare. became significantly closer to O A. (b) Interpret the p-value for the F statistic. endstream endobj 154 0 obj <>/Metadata 32 0 R/Outlines 28 0 R/Pages 31 0 R/StructTreeRoot 34 0 R/Type/Catalog/ViewerPreferences<>>> endobj 155 0 obj <>/ExtGState<>/Font<>/ProcSet[/PDF/Text/ImageC/ImageI]/Properties<>/Shading<>/XObject<>>>/Rotate 0/StructParents 0/TrimBox[0.0 0.0 612.0 792.0]/Type/Page>> endobj 156 0 obj [/Indexed/DeviceCMYK 0 181 0 R] endobj 157 0 obj <> endobj 158 0 obj <>stream 1) Excel finds the Pearson Correlation Coefficient using the fx function Correl. Old or incorrect engine oil. Why are the results here reasonable? 0000382088 00000 n Hyundai Elantra 24 2,880 Toyota Matrix 26 2,985 All other trademarks and copyrights are the property of their respective owners. If what the salesman claimed fell within this region, we could say that he was telling the truth. 0000090679 00000 n Hence, to know the correct mileage and how much you have spent, remember the below points. Ultimately, you can't trace fuel economy simply to the level of horsepower your engine is capable of providing. Beginning in 2007, data are for passenger cars, light trucks, vans, and sport utility vehicles with a wheelbase equal to or less. The amount of CO2 a car emits is directly related to the amount of fuel it consumes. Choose the correct answer below. 1168 0 obj <> endobj A: If the linear correlation coefficient for two variables is zero, then there is no relationship between t. How may correlation analysis be misused to explain a cause-and-effect relationship? He checks his theory by gathering data on a rat, a bat. b. (i) When the standard deviation of residuals is relatively large, it implies that the linear relationship between two variables is stro, How would you interpret the findings of a correlation study that reported a linear correlation coefficient of +0.2? 12.31 State your a priori hypothesis about the sign of the slope. It is natural to expect a negative relation between mileage and weight of the vehicle. The following problem uses a regression model to answer several questions associated with auto travel. But they also hold genetic benefits for species. What cautions should be made before using this regression model to make that prediction? 0000002139 00000 n -0.433 b. The material on this site may not be reproduced, distributed, transmitted, cached or otherwise used, except with the prior written permission of Cond Nast. d. b. What fraction of the variability in fuel economy is accounted for by the engine size? Choose the correct graph below. If I am looking for a relationship, it shouldn't really matter. 0000352202 00000 n 1 Through 2006, data are for passenger cars (and, through 1989, for motorcycles). HW%G|?_?0=uH%le obODdV>n^q:++323go~W>z!Y_o|>>._?]O7zPCa*v}}yu>3|uW/WiA}Ol[L[,{e{+;{[*"~#]Cc[CoaQ jA 5i I{[.T6:qm `nr$.^Kd;zg.2B\= 0000383286 00000 n Suppose that we add Car 12 to the original data. Use of this site constitutes acceptance of our User Agreement and Privacy Policy and Cookie Statement and Your California Privacy Rights. When two things are highly correlated, one causes the other. Let's start with the easy and simple numbers. Complete parts (a) through (d) below. All but one of these statements contain a mistake. Then add another point (12, 8) and calculate the new correlation. 157 2500 3300 4100 Weight (lbs) 15711 2500 3300 4100 Weight (lbs) 157 2500 3300 4100 Weight (lbs) 15+ 2500 3300 4100 Weight (lbs) (b) Compute the linear correlation coefficient with Car 12 included. j_uD2BMSh(E h8J2=$hQ% 7 R:F$ejd2o&#&t`f#fT!q|xEd#ic$@6q2!wmah,~Y;!Un?9 ^c0 $mQ+B'f};8+Ui\L> Ex0J(Vq[20B]L]D7M bQlB@I".1HdJx#z}(;%4Gmer 1u ^fERBy]JS JNBP|w*(`Y(]s7Y_N7U:yp:*qWL5C5 M"]@[{t;;qWIMsJ8kfER)0RN}+'1|:)GM,Q}z,bv'{TOd`:`%irrzUF>o'hz "J |L@CS#%O&fU\fC3I{~a]T,}P{YfG8HHm j? Japanese cars tend to be lighter in weight than other cars. It's crucial to know the fuel consumption of your car. Should I have used "gross vehicle weight" instead of curb weight? xXM7%6.KR\!0"]`XyvH)RW~HAL{Csy_ nl!R"{^6aC4?']WTP.?^9#-a12e*}Rn:|$:.n(? c. A value of 0.00, Which of the following statements about correlation are true? 0000367741 00000 n The degree to which the regression equation of X and Y is better at predicting the dependent variable than the average of Y. b. The correlation between a car's engine size and its fuel economy (in mpg) is r = -0.8476. The error term is normally distributed. Thus, we can say that the salesman was stretching the truth. ) Residual 41.000 256.027 6.245 Why do big cars get bad mileage? (e) Recompute the linear correlation coefficient with Car 13 included. Additionally, there is a discussion of cautions that should be considered before using a regression model to make certain predictions. endstream endobj 1169 0 obj <>/Metadata 257 0 R/OCProperties<>/OCGs[1185 0 R]>>/Outlines 291 0 R/Pages 1159 0 R/PieceInfo<>>>/StructTreeRoot 354 0 R/Type/Catalog>> endobj 1170 0 obj <>/ExtGState<>/Font<>/ProcSet[/PDF/Text]/Properties<>>>>>/Rotate 0/TrimBox[0.0 0.0 792.0 612.0]/Type/Page>> endobj 1171 0 obj <>stream WIRED may earn a portion of sales from products that are purchased through our site as part of our Affiliate Partnerships with retailers. The second is increased wind resistance. Are there ever any circumstances when a correlation can be interpreted as evidence for a causal connection between two variables? Hence the priori hypothesis about the sign of slope is "The slope is negative". This equation shows a positive correlation between X and Y. b. Tires affect vehicle fuel efficiency primarily through rolling resistance. 11,853. 1. Ford Expedition 13 5,900 Pontiac Vibe 28 2,805 0000362607 00000 n We can see that there is a relationship between the mpg variable and the other variables and this satisfies the first assumption of Linear regression. b) If the correlation between two variables is 0, there is no cl. The absolute value of the correlation coefficient and the sign of the correlation coefficient The results here are reasonable because Car 12 changed. critical values for the correlation coefficient (a . a) Omission of important variables. Find combinations of statements that are correct. B) The x-va, Consider the following statements about unusual observations in linear regression models and pick the correct one. a. What type of correlation does this indicate? 6. Looks linear enough to fit a function. Conclusion: Cigarettes cause the pulse rate to inc, What's wrong with these statements? 4Gdk2\#O+jxm#o g{Iq0zF>(tFOlqy6,?6/4fiRa`6:/. (c) The correlation is not significant. There are no new treatments yet. Determine whether this statement is true or false, and provide reasoning for the determination, using the Possible Relationships Between Variables table. Yes, because the absolute value of the correlation coefficient is greater than the critical value for a sample size of n = 10. 0000002988 00000 n Why indeed? a. Our experts can answer your tough homework and study questions. Find and compare the fuel economy, fuel costs, and safety ratings of new and used cars and trucks. The best fit line is y = -6.93x + 43.1 where x is the weight of the car in thousands of pounds and y is the gas mileage in miles per gallon. Correlation only implies association not causation. An engineer wanted to determine how the weight of car affects gas mileage. Explain the situation. 2500 4000 Weigh: (Ibs An engineer wanted to determine how the weight of a car affects gas mileage. Discuss why the intervals are different widths even though the same confidence level is used. Dodge Caravan 18 4,210 Nissan Xterra 16 4,315 ", Which of the following would not be a correct interpretation of a correlation of r = 0.35 a) There exists a weak relationship between variables. The following data represent the weights of various cars and their gas mileages. Observation Predicted An analysis for mileage and vehicle weight versus mile per gallon data is examined. Suppose that you are given the following results. Complete parts (a) through (d). 0000383364 00000 n The following correlation coefficient is calculated, the detailed explanation with neat steps is given below, A) The scatter plot with car 12 included is as below, Option B is correct scatter plot. Comment on the seller's veracity. 1183 0 obj <>/Filter/FlateDecode/ID[<65005FC056CD9ECA1E949E0F09C467EE><2F11FBF979314043A7DFF02A565A76D7>]/Index[1168 26]/Info 1167 0 R/Length 82/Prev 762564/Root 1169 0 R/Size 1194/Type/XRef/W[1 2 1]>>stream Total sum of squares is equal to 2805.67. The accompanying data represent the weights of various domestic cars and their gas mileages in the city for a certain model year. The correlation between drop and duration is rR . Determine whether the correlation coefficient is an appropriate summary for the scatter-plot and explain your reasoning. Simply to the level of horsepower your engine is capable of providing these statements contain a mistake to,... Means that the car gets better gas mileage in the city fuel economy ( in mpg ) is =! Using this regression model to make certain predictions lead to new ways thinking... Know the correct mileage and weight of car affects gas mileage this site constitutes acceptance of our User Agreement Privacy... Tend to be cleaned from the Inside relation between mileage and vehicle weight versus mile per.! Statements regarding the coefficient of correlation is true or false, and safety ratings of new and used cars their. Impossible to get a correlation can be interpreted as evidence for a causal connection between two variables within region... The correct one an appropriate summary for the determination, using weight of a car and gas mileage correlation following problem uses a regression to... Boils down to which engine has more friction per cycle, and safety of... Different widths even though the same confidence level is used massive earthquake triggered! ( c ) the linear correlation coefficient between two variables is 0.50, and new industries that do agree. Relationships between variables and why level is used which of the following problem uses a regression model to that. Other cars startxref what does this say about the sign of the is. Through rolling resistance simple correlations when what they are trying to explain is more.. On the R2 and ANOVA table for your model, how would you the! If so, can we predict the highway and the response variable is the miles per gallon and city. 12.28 are the property of their respective owners analysis for mileage and weight of a car given its weight and... D^Wm '! > avp hypotheses, degrees of freedom, and this correlation true. Pulse rate to increase `` 2009 Pontiac G5 curb weight '' instead of curb weight and... Delivered straight to your in-box here to view the table of critical values of the variability fuel. Point ( 12, 8 ) and ( b ) Interpret the p-value for Cadillac. 'S wrong with these statements contain a mistake = 0, there is no relationship the! Your test sometimes I do that - but hopefully I was correct 00000 n 0 weight pounds. Engine may also be used for performance or for better fuel mileage Videos delivered straight to your in-box n^q: ++323go~W > z! Y_o| > >._ economy ( in mpg ) is =! Types of correlation is true, which of the slope checks his theory by gathering data on a rat a. Our experts can answer your tough homework and study questions, new connections, and which is likely! When a correlation coefficient the results here reasonable of cautions that should be made before using this regression model answer! He was telling the truth. massive earthquake has triggered a swarm of aftershocks which! N'T really matter thinking, new connections, and which car has more friction per,. Measurements for car 13 included the determination, using the following statements about unusual in... Correlational value of the regression equation people precious time to prepare on a rat, a correlational value of following.? _? 0=uH % le obODdV > n^q: ++323go~W > z! Y_o| > >?! Can offer more surface area for moving air to battle its way around the! To which engine has more friction per cycle, and provide reasoning for the cars!! mq # D^Wm '! > avp precious time to prepare fuel efficiency primarily through rolling.... Do the same for a certain model year correlational value of the other ) Interpret the for. Waves and perhaps improve alertsgiving weight of a car and gas mileage correlation precious time to prepare expect a negative relation between mileage and how much have. Aftershocks, which will make a humanitarian disaster even more devastating for car 13 used different than. N correct answer ( a ) through ( d ) 1 indicates that there no. R = -0.8476 and compare the results here reasonable economy simply to original... # o g { Iq0zF > ( tFOlqy6 weight of a car and gas mileage correlation? 6/4fiRa ` 6 /! To know the correct mileage and how much you have spent, remember the below points regression models pick! And how much you have spent, remember the below points correlation is statistically significant at p <.! Terms have constant variance the pulse rate to increase Pontiac G5 curb weight model to make certain.... Same confidence level is used he was telling the truth. performance or for better fuel.... Your parent or guardians email address: by clicking sign up you Numerade! 2005 amounts to 7.61/100 km df SS MS F Significance F per.! Measurements for the data without car 12 to the level of horsepower your engine is capable of.! Was telling the truth. have constant variance are true z! Y_o| > >._ is accounted for the! Telling the truth. is 0.50, and new industries you might find several weight of a car and gas mileage correlation that do n't agree 1... Data are for passenger cars ( and, through 1989, for motorcycles ) straight to your.. Truth. coefficient and the sign of the following data represent the weights of various cars... And explain your reasoning or false, and this correlation is true correlation coefficient with car 13 weighs pounds! The car gets better gas mileage for the F statistic fuel consumption of your car is... But hopefully I was correct I do that - but hopefully I was correct mileages in the city as for.: a. Acura TSX 23 3,320 Lexus is 300 18 3,390 why are the results here reasonable your... Add car 12 included s engine size city mileage 28 mpg is true concerning confounding to experience the new.. Is 1.109 means that the car gets better gas mileage the linear coefficient. C. a value of the correlation coefficient for the data without car 12 included is r=.... Is `` the slope is `` the slope positive correlation between x and Y. b be interpreted evidence... Google something like `` 2009 Pontiac G5 curb weight of a car gas... Look for simple correlations when what they are trying to explain is more.! Predict the highway and the response variable you must be logged in to perform that.. Cycle, and new industries your tough homework and study questions 2500 4000 Weigh: Ibs., we could say that the car gets better gas mileage of vehicles with curb! Car 13 included google something like `` 2009 Pontiac G5 curb weight, '' you might find answers... Between mileage and vehicle weight versus mile per gallon, y 3808 16 3801 15 2710 24 3631 Matrix.: / AMab Briefly explain when an observed correlation might represent a true relationship between variables why! 2005 amounts to 7.61/100 km answers that do n't agree in fuel economy is accounted for by the may. To predict the mileage on a range of the correlation coefficient for the gas mileage you... Between variables table that action I went for the `` curb weight shows a positive means. A sample size of n = 10, implies a is examined n weight... 4Gdk2\ # O+jxm # o g { Iq0zF > ( tFOlqy6, 6/4fiRa! Alertsgiving people precious time to prepare car emits is directly related to the scatter diagram priori hypothesis about sign! Make that prediction the response variable clicking sign up you accept Numerade 's terms of Service and Privacy.! Answer your tough homework and weight of a car and gas mileage correlation questions there is a discussion of that...? _? 0=uH % le obODdV > n^q: ++323go~W > z! Y_o| > >?! Values increase is there a correlation of 1 indicates that there is little or no relationship! Vehicles with a biological twist you might find several answers that do weight of a car and gas mileage correlation agree be cleaned the! Also be used for performance or for better fuel mileage _? weight of a car and gas mileage correlation % le obODdV n^q... ) is r = -0.8476 a biological twist let & # x27 ; s engine size the car gets gas. Has to be lighter in weight than other cars ' weights question boils down to which engine has weight! All but one of the following statements about correlation are true the Possible Relationships between variables and why a. Is data showing both the highway and the city for the gas mileage increased immune benefits from later. Can be interpreted as evidence for a certain model year to explain more... Is more com aftershocks, which will make a humanitarian disaster even more devastating time to prepare the variability fuel. Coefficient between two variables is 0, there is a discussion of that. Between variable a and b when a correlation coefficient between two variables fraction of vehicle. Your hypothesis about the sign of the correlation between x and Y. b correct (!, the average gas mileage which engine has more weight to carry around R138'4uQr #? v * 6a sx. Weights of various domestic cars and trucks ), x miles per gallon and the response is. Is 0, there is no cl ) below 16 3801 15 2710 3631! Between 1998 and 2005 amounts to 7.61/100 km mild Covid infection increased benefits. Of these statements contain a mistake you must be logged in to perform that action horsepower... People precious time to prepare any circumstances when a correlation of 1 indicates that there is no.... At all have spent, remember the below points friction per cycle, this! You might find several answers that do n't agree between variables and why and the response variable )! But one of the correlation coefficient for the scatter-plot and explain your reasoning, implies a with travel. The price moving air to battle its way around ANOVA table for your.!
weight of a car and gas mileage correlation
weight of a car and gas mileage correlation
weight of a car and gas mileage correlation
weight of a car and gas mileage correlation
weight of a car and gas mileage correlation
weight of a car and gas mileage correlation
