maix stat exam 2010 q3: an experiment is a study design that allows us to prove a cause-and- effect...

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MAIX STAT EXAM 2010 Q3: An experiment is a study design that allows us to prove a cause-and-effect relationship. A (comparative) experiment: I. Manipulates factor levels to create treatments. II. Randomly assigns subjects to these treatment levels. III. Compares the responses of the subject groups across treatment levels. A. I B. II C. III D. I and II E. I and III F. II and III G. ALL OF THE ABOVE H. NONE OF THE ABOVE

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MAIX STAT EXAM 2010 Q3: An experiment is a study design that allows us to prove a cause-and-

effect relationship. A (comparative) experiment:I. Manipulates factor levels to create treatments.

II. Randomly assigns subjects to these treatment levels.

III. Compares the responses of the subject groups across treatment levels.

A. I

B. II

C. III

D. I and II

E. I and III

F. II and III

G. ALL OF THE ABOVE

H. NONE OF THE ABOVE

MAIX STAT EXAM 2010

Data in JMP is (are) organized numbers and or characters with a context where the rows refer to the “WHAT” and the columns to the “WHO” of the study data

A)AGREEB)DISSAGREE

MAIX STAT EXAM 2010

In the following table of car data.

Level Count

American 212

Asian 102

European 45

TOTAL 359

What is the FREQ and REL FREQ of “Europen CARS”?

a) 212 and 0.591= (212/359)

b) 102 and 0.284=(102/359)

c) 45 and 0.125=( 45/359)

d) ALL of the ABOVE

American

Asian

European

50 150

Count

.10 .30.50

Probability

212

102

45

American

Asian

European

MAIX STAT EXAM 2010 Wish of the following statements about the Standard Normal Density

(z tables) is NOT TRUE

a) It ALWAYS has mean 0 and variance 1

b) It is derived from ANY Normal Density if we “standardize” it by subtracting its mean and dividing by its standard deviation

c) Tables of it can be found in any STAT book and it could be used to answer ALL questions concerning ANY NORMAL distributions

d) ALL of the above

e) NONE of the above

MAIX STAT EXAM 2010

What is the correct answer for the std dev of the following set: 22,23,24,25,26.

a) zero

b) 1

c) 2.49

d) 2.5

e) SQRT(2.5)

f) None

MAIX STAT EXAM 2010 The picture supplied represents the age distributions

(for those 33 that submitted their personal info).

Q) a)Is the mean larger than the median for age (years) and b) is the distribution positively skewed

a) AGREE (YES & YES)

b) DISSAGREE (YES, NO)

c) DISSAGREE (NO, YES)

d) DISSAGREE (NO, NO)

MAIX STAT EXAM 2010

The picture supplied represents the age distribution (for those 33 that submitted their personal info).

Q) a)The IQR is 3 years and

b) because of that only students younger than 19.5 and older than 28 should be marked as outliers.

a) AGREE (YES & YES)

b) DISSAGREE (YES, NO)

c) DISSAGREE (NO, YES)

d) DISSAGREE (NO, NO)

MAIX STAT EXAM 2010 The picture supplied represents the age and sex distributions (for

those 33 that submitted their personal info).

Q) a)The standard Err Mean is calculateda) Std Dev / 32

b) Std Dev / 33

c) Std Dev / SQRT(32)

d) Std Dev / SQRT(33)

MAIX STAT EXAM 2010 The picture supplied represents the age and sex distributions (for

those 33 that submitted their personal info).

Q) Is the mean age significantly different than 24 (years) based on the 95% CI provided

a) AGREE

b) DISSAGREE

MAIX STAT EXAM 2010

The picture supplied represents the age and sex distributions (for those 33 that submitted their personal info).

Q) To test the one-tail alternative that the mean age is Higher (>24) then we should reject the null

a) AGREE (reject Ho)

b) DISSAGREE (fail to reject Ho)

MAIX STAT EXAM 2010 Q1: If weight was measured in kilograms (kg) and height was

measured in centimeters (cm) then if their correlation was .72 then it’s units are in ___.

a) kg*cm

b) kg/cm

c) cm/kg

d) NONE of the above (it does not have units)

MAIX STAT EXAM 2010 Q1: If weight was measured in kilograms (kg) and height was

measured in centimeters (cm) then if their correlation was .72 then we can conclude RSquare=(.72)2 > .5 which implies that both a little over 50% of the variations in weight can be explained by height and vise versa.

a) AGREE

b) DISSAGREE

MAIX STAT EXAM 2010

The picture supplied represents the Weight (kg) to Height (cm) (for those 33 that submitted their personal info).

Q) a) Is the a significant negative linear relationship

b) The RSquare is >50%

a) AGREE (YES & YES)

b) DISSAGREE (YES, NO)

c) DISSAGREE (NO, YES)

d) DISSAGREE (NO, NO)

MAIX STAT EXAM 2010

The picture supplied represents the Weight (kilos) to Height (cm) (for those 33 that submitted their personal info).

Q) a) Did you agree from the least

squares line that for every one cm that

“you grow”(height) we should expect

on average that your weight will

increase by less than one Kilo

a) AGREE

b) DISSAGREE

MAIX STAT EXAM 2010 The analysis of AGE by SEX for those 33…

Q) a) Did you agree

something MUST BE WRONG

since it appears that a 34 year old M is

is not an outlier when both 33 and 34 year old females are “appearing too old” since they are marked as outliers.

a) AGREE

b) DISSAGREE

MAIX STAT EXAM 2010

The analysis of AGE by SEX for those 33…

The two tail test for testing the null hypothesis of no difference in the average age of males and females (STAT MAIX students) against the two tail alternative leads us to reject the null

a) AGREE

b) DISSAGREE

MAIX STAT EXAM 2010

Q2) Under the null hypothesis of (independence) the expected (E) number of low birth weight babies born to smoking mothers is

189* (74/189)*(59/189)=23.1

A.TRUE

B.FALSE

Q3) The (2,2) cell Chi Square contribution is calculated by using the observed (O=30) and expected (E=23.1) by the following formula

A. (E-O)2 / O

B. (E-O) / E

C. (O-E)2 / E

D. (O-E) / E

E. NONE OF THE ABOVE

MAIX STAT EXAM 2010

MAIX STAT EXAM 2010 Q4) The Pearson overall Chi Square

statistic for testing the Ho null hypothesis of independence is calculated by summing the cell Chi squares contributions with (2-1)*(3-1)=2 degrees of freedom (d.f.) for each cell and the conclusion is

A. TRUE and NOT reject Ho

B. FALSE and reject Ho

C. TRUE and reject Ho.

D. FALSE and reject Ho E. NONE OF THE ABOVE

MAIX STAT EXAM 2010

The objectives of simple linear regression are:a) To compare the values of the response variable given the

identification level of a nominal predictor variable.b) To assess the significance of the predictor variable in explaining

the variability or behavior of the response variablec) To predict the values of the response variable given the values of

the predictor variable.d) ALL OF THE ABOVEe) B and C only

MAIX STAT EXAM 2010 A pharmaceutical manufacturer would like to be able to claim that its new headache relief medication is better than those of rivals. Also it has two methods fro formulating its product, and it would like to compare these as well. From a small experiment use the data HEADACHE.JMP In the data set from this small experiment the categories in the column Drug are: (1) active component #1, (2) active compound #2, (3) rival product and (4) control group (aspirin).

Q) Is the test that we use to compare the four drugs here an extension of Two-Group t test other ways called one-way Anova test

A. AGREEB. DISSAGREE

MAIX STAT EXAM 2010

What decision can be reached from these data without changes:

a) Reject the null

b) Fail to reject the null at the 5% alpha level.

c) Cannot tell

-20

-10

0

10

20

30

Pain

Relie

f

Active 1 Active 2 Control Rival

Drug

Drug

Error

C. Total

Source

3

61

64

DF

501.2687

4236.0334

4737.3022

Sum of Squares

167.090

69.443

Mean Square

2.4061

F Ratio

0.0759

Prob > F

Analysis of Variance

Oneway Anova

Oneway Analysis of PainRelief By Drug

MAIX STAT EXAM 2010 Failing to reject a FALSE null hypothesis “translates to letting a criminal go free” which is usually refer to as Type II Error

A. AGREE

B. Dissagree

MAIX STAT EXAM 2010 We always reject the null hypothesis if the P value

is SMALLER than the alpha level of significance (usually 5% that we usually refer to as Type I Error).

A. AGREE

B. DISSAGREE

MAIX STAT EXAM 2010 The Central Limit Theorem (CLT) states that ________ , the sampling distribution of the sample mean of samples of size n drawn from the same population will approach a ____ distribution, In addition we know that this distribution will have a mean equal to the population mean and a std deviation equal to ______________.

1 n increases, 2 population std. deviation , 3 population mean

4 / n , 5 Normal , 6 Uniform, 7 population median, 8 IQR/n A. 1, 5, 8,B. 1, 5, 2, C. 6, 2, 7,D. 6, 2, 8,E. NONE OF THE ABOVE

A level C confidence interval for a ________ has two parts.• An interval of the form ______ __________ • A ______ C, which gives the ______________ that

__________________.1) zero , 2) two sigma, 3) confidence level, 4) interval found this way catch the parameter value, 5) margin of error 6)population parameter, 7) probability 8) sample 9) sampling distribution 10) statistic 11) the parameter equals the statistica) 6, 10, 5, 3, 7, 4b) 10, 6, 5, 3, 7, 11c) 6, 10, 5, 3, 7, 11 d) 10, 6, 5, 3, 7, 4 e) NONE OF THE ABOVE

MAIX STAT EXAM 2010

MAIX STAT EXAM 2010

General Addition Rule:For any two events A and B,

P(A or B) = P(A) + P(B) + P(A and B)

If the events are mutually disjoint then the above formula becomes

P(A or B) = P(A) + P(B) since P(A and B) =0

A. TRUE

B. FALSE

MAIX STAT EXAM 2010 The general multiplication rule states that

A. The P(A and B)= P(A) + P(B|A)

B. The P(A and B)= P(B) + P(A|B)

C. Reduces to the multiplication rule if A and B are independent that is P(A and B) = P(A)*P(B)

D. ALL OF THE ABOVE

E. NONE OF THE ABOVE

MAIX STAT EXAM 2010 The graph display to help us investigate how RAIN relates to ALTITUDE, LATITUDE AND COASTDIST is called:

a) Segmented bar chart

b) Histogram

c) Stem and leaf plot

d) Scatterplot(s)

e) NONE of the above

MAIX STAT EXAM 2010

(A) AGREE, (B) DISSAGREE The graph display below to investigate how RAIN relates to

ALTITUDE, LATITUDE AND COASTDIST suggests the following conclusions about the correlations:

WEAK +, MODERATE + , WEAK -

MAIX STAT EXAM 2010 A manufacturer claims that lifespan for their copy machines (in months) can be described by a Normal model N (=42,=7). What percent we expect to still work beyond the first 35 months

a) 25%

b) .50

c) 75%

d) .95

e) NONE OF THE ABOVE

MAIX STAT EXAM 2010 The best defense against bias is randomization in which each individual is given a fair random choice of selection. Nevertheless most Sample Surveys suffer (things that might go bad that will usually result) with some form of bias such as:

I) Undercoverage II) Nonresponse bias III) Voluntary response bias IV) Response bias

A. I B. IIC. IIID. IVE. NONE OF THE ABOVE F. USUALLY MORE THAN ONE OF THE ABOVE

MAIX STAT EXAM 2010 Q3: An experiment is a study design that allows us to prove a cause-and-

effect relationship. A (comparative) experiment:I. Manipulates factor levels to create treatments.

II. Randomly assigns subjects to these treatment levels.

III. Compares the responses of the subject groups across treatment levels.

A. I

B. II

C. III

D. I and II

E. I and III

F. II and III

G. ALL OF THE ABOVE

H. NONE OF THE ABOVE