michelle ji, sam shober, april zhang. goal: assess dietary needs of people in our area determine...
TRANSCRIPT
Michelle Ji, Sam Shober, April Zhang
Dietary Needs
Our TopicGoal: Assess dietary needs
of people in our areaDetermine whether men or
women were picker eatersConducted survey that
asked participants if any of the following were applicable:VegetarianDiabeticAllergic to any foodsDietingA picky eater
Took note of age range and gender
Oral Surveying ProcedureSystematic Random
Surveying Method Choose
shopping/entertainment centers with heavy foot traffic
RandInt locations to use
Survey every third person that passes
Pros: wide variety of people in
older age groupsCons:
Few teenagers Inconclusive data for
testingFewer non-response than
Facebook surveyingConclusion:
Most accurate/representative overall
Facebook ProcedureSystematic Facebook
Surveying MethodMake event and
invite all friendsEvery third response
is counted in data
Pros:More than 400 responsesReceived more data that
was in our favorConditions met proceed
to testing
Cons:Only two people outside
of 15-20 age rangeConclusion:
Most amount of data overall and in allowed us to test
Most representative of teenage age range
Background InformationVegetarianism
Lacto-Ovo (milk & eggs)Ovo (only eggs)Lacto (only milk)Pescatarian (fish & seafood)Strict (no meat/dairy/eggs
but other animal products allowed)
Vegan (no animal products for consumption or use)
Vegetarian Stats (2008)7.3 million Americans are
vegetarians3.2% of Americans are
vegetarians
Background InformationVegetarians
59% female 41% male 42% 18-34 years old 40.7% 35-54 years old 17.4% over 55 years old
Food Allergies 4% of Americans have food
allergies 6% of children have food
allergies 2% of adults have food allergies
60% female, 40% male Tree nuts, peanuts, milk, eggs,
soy, wheat, fish, shellfish account for 90% of food allergies
Background InformationDieting
Dieting industry earned 55 billion dollars in 2006
Estimated 72 million dieters in US
In last 10 years, 70% of females and 30% of males have been on a diet1/3 of women and ¼
of men are currently on a diet
Background InformationDiabetes25.8 million people
have diabetes8.3% population0.26% people under 20 11.3% people above 2026.9% people above 6511.8% men 20 or older10.8% women 20 or
older
Pre-Survey/Test PredictionsFemales will
demonstrate pickier eating habits than males ie, more females will
identify themselves as having a food allergy, being vegetarian, or being on a diet
Prediction based on personal experience as well as commentary from some survey participants
Exploratory Analysis: Gender and Dieting
In our sample…11.67% of females were on
a diet4.76% of males were on a
dietConclusion:More females than males in
Bucks and Montgomery County that frequent shopping and entertainment centers are on a diet.
More likely that any given male or female will not be on a diet rather than on a diet
Dietno yes
20
40
60
80
100
120
140
Gender
F M
count
Collection 3 Bar Chart
Collection 3
RowSummary
Column Summary
Diet
yes
Diet
no
F
MGender
120 14
84 4
204 18
134
88
222
S1 = count
Exploratory Analysis:Age and Dieting
In our sample… 6.15% of teens were on a diet 9.09% of young adults on a diet 17.5% of middle age adults were
on a diet 0% of senior citizens were on a
diet
Conclusion: Middle aged adults (age 31-59)
are more likely to be on a diet than any other age group
Very rare to find senior citizens on a diet in Bucks/Montgomery County
In all age groups, it is more likely to find someone not on a diet than on a diet.
Dietno yes
40
80
120
Age
15-20 21-30 31-59 60+
count
RowSummary
Column Summary
Diet
yes
Diet
no
15-20
21-30
31-59
60+
Age
122 8
30 3
33 7
19 0
204 18
130
33
40
19
222
S1 = count
Exploratory Analysis:Vegetarians (In general)
In our sample,6.31% of people
were vegetarians93.69% of people
were not vegetariansConclusion:Most people in the
Bucks and Montgomery area are not vegetarians
40
80
120
160
200
Vegetarian_Y_N
no yes
count
Collection 3 Bar Chart
Collection 3
RowSummary
Vegetarian_Y_N
yes
Vegetarian_Y_N
no
208 14 222
S1 = count
1 Prop Z Test
State Check* SRS * random sample* np * 222(.0631) nq > 10 222(.9369) >10* pop > 10n * all vegetarians > 2220conditions met normal model 1 Prop Z Test
032.:
032.:0pH
pH
A
p= .0631n=220
^
^
Determine if the proportion of vegetarians in Bucks/Montgomery County is equal to the proportion across America.
^
1 Prop Z Test
= 2.6297
P(z>2.6297)= .0043
We reject the Ho because our p-value of .0043 is less than an alpha level of .05.
We have sufficient evidence that the proportion of vegetarians is greater than 3.2%.
Therefore, we can conclude that the proportion of vegetarians in Bucks and Montgomery County is greater than the proportion of vegetarians all across America.
p= .0631n=220
^
npp
ppz
)1(
ˆ
Exploratory Analysis:Picky Eaters by Gender
In our sample,15.9% of males were picky
eaters19.4% of females were picky
eatersConclusion:Both males and females are
more likely to not be a picky eaters than to be a picky eaters.
It appears as if there are more female picky eaters than male picky eaters. To be sure, we need a 2 Prop Z test…
Pickyno yes
20
40
60
80
100
120
140
Gender
F M
count
Collection 3 Bar Chart
RowSummary
Column Summary
Gender
M
Gender
F
no
yesPicky
108 74
26 14
134 88
182
40
222
S1 = count
2 Prop Z TestTo determine if a larger proportion of Bucks/Montgomery County women identify themselves as picky eaters compared to Bucks/Montgomery County men.
State Check*2 independent SRS * random sample* nWpW * 134(.194) nWqW > 10 134(.806) > 10 nMpM 88(.1591)
nMqM 88(.8409)
* popW > 10nW *all female picky eaters > 1340
popM > 10nM * all male picky eaters > 880
conditions met normal distribution 2 Prop Z test
pW= .194 pM=.1591nw=134nM=88
^
^
^
^
^ ^
2 Prop Z Test
= .6625
P(z>.7134)= .2538
We fail to reject the Ho because our p-value of .2538 is greater than an alpha level of .05.
We have sufficient evidence that the proportion of Bucks/Montgomery County female picky eaters is equal to the proportion of Bucks/Montgomery County male picky eaters.
MW
MW
nqp
nqp
ppz
ˆˆ
ˆˆ
MWA ppH
ppH MW
:
:0
^ ^
Exploratory Analysis:Gender and Food Allergies
In our sample…18.66% of females had food
allergies6.8% of males had food
allergiesConclusion:More likely to find a male or a
female without food allergies than with food allergies.
It appears that females are twice as likely to have food allergies than males.
To be sure these variables are related, we need a x2 test of homogeneity…
RowSummary
Column Summary
Allergies_YN
yes
Allergies_YN
no
F
MGender
109 25
82 6
191 31
134
88
222
S1 = count
Allergies_YNno yes
40
80
120
Gender
F M
count
X2 Test For HomogeneityTo determine if food allergies is related to gender.
State Check*Categorical * Gender and allergiesdata are categorical*SRS * Random sample* All expected * all expected cell countscell counts > 5 > 5
conditions met x2 distribution x2 test for homogeneity
Collection 3
RowSummary
Column Summary
Allergies_YN
yes
Allergies_YN
no
F
MGender
109 25
82 6
191 31
134
88
222
S1 = count
X2 Test For HomogeneityHo: There is no association between gender and food
allergies.Ha: There is an association between gender and
food allergies.
=6.1962P(X2>6.1962)=.0128 df=1
We reject the Ho because our p-value of .0128 is less than an alpha of .05.
We have sufficient evidence that there is an association between gender and food allergies.
...712.18
)712.1825(
29.115
)29.115109(
exp
)exp( 2222
ected
ectedobserved
ApplicationWomen in Bucks/Montgomery County
are more likely to have food allergies.However, our 2 Prop Z Test shows that
the proportion of female picky eaters is equal to the proportion of male picky eaters in Bucks/Montgomery County.
ApplicationProportion of vegetarians in
our area is greater than the proportion throughout AmericaCould be because of difference
in years (the study we referenced came from 2008)Concern with healthy eating
habits might have peaked since 2008more people may start becoming vegetarian
Or, our area could be more open to vegetarianism and healthy eating than other places throughout the country
Bias and Error No foot traffic at certain
locations Voluntary response bias
Facebook and man at Genaurdi’s
People carrying heavy loads, on the phone, walk past us, have little kids, listening to music, etc
Systematic random sampling is not an ideal method Explaining Large Groups
Wording of questions AP vs. High School
Non response bias People’s personal opinions or
perceptions Flexi-tarian, healthy eaters,
etc Age groups
15-20 on Facebook Older people at grocery stores
Stores closed at the times we want to survey
People giving unserious answers
Under-coverage People away for Memorial
Weekend or not out shopping while we were conducting our survey
Personal OpinionsSurveying in person is
definitely one if not the most difficult type of data collection Encounter strange people Probably will never be
utilized again, for any future projects (unless required)
Facebook data collection is the most efficient if you have many ‘friends’ But will probably be the
most biasedSurprised that women and
men were equally ‘picky’ eaters
Conclusions/Recap of Data Dieting:
Females > males in Bucks/Montgomery County on diet
31-59 most likely to be on diet Senior citizens will most likely NOT
be on a diet Residents in this area more likely
NOT to be on diet Vegetarians:
Most people in the Bucks/ Montgomery are not vegetarians
Proportion of vegetarians in Bucks/ Montgomery > proportion of vegetarians across America
Picky Eating: Proportion of female and male picky
eaters in Bucks/Montgomery County are the same
Males and females within this area are more likely to NOT be picky eaters
Food Allergies There is an association between gender
and food allergies Females > males
More likely to NOT have food allergies in Bucks/Montgomery
Surveying: Some methods better than others
Depends on time allotted and results you are hoping to get
Future Try different surveying methods Survey according to time of day
Attempted but was futile Survey more people Survey in a wider variety of places Make sure all questions are the same
when asked Be more clear about restrictions
Definition of picky eater/vegetarian is different depending on the person
Overall Conclusion: It is not likely to find picky eaters (in general) in the Bucks/Montgomery County area whether out of choice or inevitability.
Observations While Surveying“Save the world”Asking for a prize“REJECT THE NULL
HYPOTHESIS!”Voluntary response bias
NOT through Facebook2nd person in our
survey came up to April and asked to answer the questions
“See Food Diet”Couples and Picky
Eating