coke phase ii 2

8/2/2019 Coke Phase II 2

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Running head: COKE ANALYSIS 1

Coke Analysis

Katie Votaw

Stats-1510

Taft College


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COKE ANALYSIS 2

Abstract

The purpose of this experiment is to determine if there is any significant variation in weight

between Diet Coke, Diet Pepsi, and Coke Zero. My hypothesis was that there would be no

difference in the weight of each brand of soda, but that if there were that Coke Zero would weigh

less than the other soda brands. A sample of 15 cans of each soda brand was randomly selected

from a larger group of cans using the TC-Stats I-pad application. TC-Stats was also used to

construct graphical displays, frequency distribution, and summary statistics tables in order to

assist us in determining any differences between the three sets of data. After determining that

our data sets were not normally distributed we chose to use the Kruskal-Wallis technique to

determine if there were any differences. The technique concluded that there was a difference in

the data sets which allowed us to then look at the median of each set of data which brought us to

the conclusion that Diet Pepsi not only varied from the other two brands in weight, but in fact

weighed less.


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COKE ANALYSIS 3

Coke Analysis

In this experiment I will attempt to determine if there is any significant evidence to prove

there is a difference between the weights of Diet Coke, Diet Pepsi, and Coke Zero products in a

can. Prior to collecting my data and finding my results my hypothesis is that there will not be

any significant difference in the weight between each of the different sodas due to the fact that

all are considered to be diet sodas and all contain the same fl. oz of product within the can. I

also feel that if there is any difference at all that Coke Zero will be the lightest only due to the

fact that it is marketed as more healthy than the other two diet soda products.

Method

Materials

A sample of 15 cans out of each products population was chosen to conduct this

experiment. A digital scale was used to weigh each of the selected cans. The TC-Stats app was

used to generate which numbered cans I would use for the simple random sample, to generate

summary statistics and graphical displays, and to apply the Kruskal-Wallis technique to the data

in order to determine if there was any significant difference between the weights of the three

brands.

Measures

While conducting this experiment we wanted to find out if there was a difference

between the weights of the canned products of Diet Pepsi, Diet Coke, and Coke Zero. In order to

find the answer I used the Kruskal-Wallis technique. The Kruskal-Wallis technique is used when

you have multiple sets of data which are not normally distributed and you want to determine if

one set of data is different from the others. While Kruskal-Wallis does not tell us who is


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COKE ANALYSIS 4

different, it tells us that there is a difference giving us the ability to reference back to the median

of each set of data to conclude which group is different from the others.

Procedure

Out of 85 total Diet Coke cans, 96 total Diet Pepsi cans, and 72 total Coke Zero cans I

used the TC-Stats I-Pad app to conduct a simple random sample of 15 cans from each group. I

then used the numbered cans selected by TC-Stats to perform my experiment. Each selected can

was weighed and the data was collected in order to create graphical displays such as histograms,

frequency distribution tables, and box-whisker plots. I then used TC-Stats to construct normal

plots of the data to determine if the ANOVA or the Kruskal-Wallis technique should be used to

determine if there was any difference between the three sets of data collected. After viewing the

normal plots it was determined that the collected data was in fact not normal. Because of this I

used the Kruskal-Wallis technique to determine if there was any difference between the sets of

data.

Results

Before conducting this experiment my hypothesis was that there would not be any

difference in the weight of the three brands of soda, but if there was any difference that Coke

Zero would weigh less than Diet Coke and Diet Pepsi because of its assumed higher health

value.

Using the Kruskal-Wallace technique with an alpha level of .05 we found significant

evidence (p-value= 0.0138) that we are to reject our null hypothesis (HO: c= p= z) that each

brand of soda will have the same weight and instead go with our alternative hypothesis (H A: At

least one ) that at least one brand of soda has a different weight. After conducting the research

my original hypothesis that there would be no difference between the weights of the three soda


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COKE ANALYSIS 5

brands was found to be incorrect. I had also stated that if there were a difference that Coke Zero

would be lighter this hypothesis was also found to be incorrect. Diet Pepsi in fact was

determined to have the lightest weight when compared to the other two soda brands.

Discussion

Based on this experiment we were able to determine there was a difference in the weight

of Diet Pepsi in a can compared to Diet Coke and Coke Zero in a can. After analyzing normal

plots of the data it was determined that the data was not normal therefore I chose to use Kruskal-

Wallis to determine if there were any differences in the data groups. Our results were that our

data at an alpha level of .05, contained a p-value of .0138 which concludes that we are to reject

the idea that there are no differences between the weights of our three soda brands. After

determining that there was a difference between the three data groups I reviewed the summary

statistics of the data. Diet Coke contained a median of 372.020, Coke Zero contained a median

of 372.090 and Diet Pepsi contained a median of 370.250 which shows us that there is enough

evidence to suggest that Diet Pepsi is different from the two other brands.


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COKE ANALYSIS 6

Figure 1: Raw data

The raw data shows the number corresponding to each soda can along its weight.

Diet Coke DataFigure 2: Diet Coke Frequency Distribution Table that shows us where the weight of the dietcoke cans is more heavily distributed.

Figure 3: Diet Coke Histogram gives us a visual display of the distribution of the diet coke

weights.

Diet Coke Numbers Diet Coke Diet Pepsi Number Diet Pepsi Coke Zero Number Coke Zero

52 369.38 50 371.03 54 373.44

60 369.64 6 370.25 66 372.12

78 374.82 88 370.6 29 372.77

22 370.79 85 370.5 65 371.32

1 370.86 32 367.79 39 374.89

73 372.14 14 366.35 12 370.34

41 370.02 75 366.57 51 371.57

9 373.24 3 372.58 18 372.09

30 373.24 52 374.47 14 368.26

59 373.2 11 369.54 33 375.84

13 373.49 74 371.33 61 371.12

21 373.54 51 369.39 52 371.164 367.97 81 370.26 8 373.46

57 370.59 29 368.84 46 373.25

45 374.9 55 367.55 64 368.5


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COKE ANALYSIS 7

Figure 4: Diet Coke Box-and-Whisker Plot shows where the median weight of the diet coke datais located.

Figure 5: Coke Zero Frequency Distribution Table shows us where the weight of the Coke Zerocans is more heavily distributed.


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COKE ANALYSIS 8

Figure 6: Coke Zero Histogram gives us a visual display of the distribution of the Coke Zeroweights.

Figure 7: Coke Zero Box-and-Whisker Plot shows where the median weight of the Coke Zero

data is located.


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COKE ANALYSIS 9

Figure 8: Diet Pepsi Frequency Distribution Table shows us where the weight of the Diet Pepsicans is more heavily distributed.

Figure 9: Diet Pepsi Histogram gives us a visual display of how the weights of the Diet PepsiCans are distributed.

Figure 10: Diet Pepsi Box-and-Whisker Plot shows us where the median weight of the Diet Pepsidata is located.


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COKE ANALYSIS 10

Figure 11, 12, & 13: Diet Coke, Coke Zero, and Diet Pepsi Normal Plots used to determinewhether to use the ANOVA or the Kruskal-Wallis technique. If the data is normal you use

ANOVA, if it is not normal you use Kruskal-Wallis.

Figure 11: Diet Coke data is not normal.


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COKE ANALYSIS 11

Figure 12: Coke Zero data is not normal.


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COKE ANALYSIS 12

Figure 13: Diet Pepsi data is not normal.


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COKE ANALYSIS 13

Figure 14: Summary Statistics for all Data shows a clear distinction between the median of theweight of Diet Pepsi and the weight of the other two brands.

Figure 15: Comparison Box-and-Whisker Plot for all Data shows a distinction between theweight of the Diet Pepsi and the weight of the other two brands.

Appendix:SourcesFigure 1 Raw Data

Figure 2 Diet Coke Frequency Distribution TableFigure 3 Diet Coke Histogram

Figure 4 Diet Coke Box-and-Whisker PlotFigure 5 Coke Zero Frequency Distribution Table

Figure 6 Coke Zero HistogramFigure 7 Coke Zero Box-and-Whisker Plot

Figure 8 Diet Pepsi Frequency Distribution TableFigure 9 Diet Pepsi Histogram

Figure 10 Diet Pepsi Box-and-Whisker PlotFigure 11 Diet Coke Normal Plot

Figure 12 Coke Zero Normal PlotFigure 13 Diet Pepsi Normal Plot

Figure 14 Summary Statistics for all DataFigure 15 Box-and-Whisker Plot for all Data

Coke Analysis Phase 1: http://katiev1985.wikispaces.com/Coke+Analysis+Phase+1


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