44 Questions
| Total Attempts: 265

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Questions and Answers

- 1.Statistics is the study of _____________.
- A.
Testing and interpreting statistical hypotheses about a relationship

- B.
Mathematical analysis using samples instead of populations

- C.
Summarizing, analyzing, or drawing inferences about a relationship

- D.
Inferring something about a population from a sample

- 2.Which of the following is not a variable?
- A.
Personal fantasies

- B.
The final score of the Yankees game on 10/17/09

- C.
Body temperatures of people who are NOT sick

- D.
Age

- 3.Why is it important to record demographics?
- A.
Different populations act differently

- B.
The IRB mandates it for studies conducted

- C.
There's no way to tell if you're measuring a consistent estimator

- D.
There's no way to tell if you're measuring a sufficient estimator

- 4.How is an ordinal variable more detailed than a nominal variable?
- A.
0 means the total absence of the variable

- B.
The categories are qualitative groupings

- C.
The categories possess value

- D.
The distance between the categories is equal

- 5.How is a ratio variable more detailed than an interval variable?
- A.
0 means the total absence of the variable

- B.
The categories are qualitative groupings

- C.
The categories possess value

- D.
The distance between the categories is equal

- 6.What kind of variable is a person's height?
- A.
Discrete

- B.
Continuous

- C.
Ungrouped

- D.
Grouped

- 7.What kind of frequency distribution is the above?
- A.
Ungrouped frequency distribution

- B.
Grouped frequency distribution

- C.
Relative frequency distribution

- D.
Cumulative frequency distribution

- 8.What kind of frequency distribution is the above?
- A.
Ungrouped frequency distribution

- B.
Grouped frequency distribution

- C.
Relative frequency distribution

- D.
Cumulative frequency distribution

- 9.What would a stem and leaf plot look like for:10, 11, 13, 13, 21, 31, 36
- A.
10, 11, 13, 13 21 31, 36

- B.
1 | 0, 1, 3, 3 2 | 1 3 | 1, 6

- C.
10s X X X X 20s X 30s XX

- D.
10s+ XXXX 20s+ XXXXX 30s+ XXXXXXX

- 10.In a positively skewed distribution, ____________.
- A.
The bulk of the scores are on the left side

- B.
The bulk of the scores are on the right side

- 11.Kurtosis is the measure of ______________.
- A.
The amount that the peak is shifted positively or negatively

- B.
The shape of the distribution's peak

- C.
Whether the distribution has enough scores (N)

- D.
The cumulative relative frequency

- 12.B would be described as being ___________.
- A.
Mezokurtic

- B.
Hypokurtic

- C.
Platykurtic

- D.
Leptokurtic

- 13.A would be described as _______________.
- A.
Mezokurtic

- B.
Hypokurtic

- C.
Platykurtic

- D.
Leptokurtic

- 14.The mode is an especially poor choice of measuring central tendency when ___________.
- A.
The distribution is bimodal

- B.
The distribution is heavily positively skewed

- C.
The distribution is leptokurtic

- D.
The distribution is a normal curve

- 15.The median is a better choice of measuring central tendency than the mean when _____________.
- A.
The distribution is bimodal

- B.
The distribution is heavily positively skewed

- C.
The distribution is leptokurtic

- D.
The distribution is a normal curve

- 16.The sum of deviations [ Summation (X-Xbar)] is always equal to ____________.
- A.
The mean

- B.
The median

- C.
0

- D.
It's possible for it to be different every time

- 17.In which of the following situations would just providing the mean without also providing variability be bad?
- A.
Giving the mean number of meters a guided missile lands from the target but not the variability

- B.
Giving the mean amount of IQ increase seen in children in a single year but not the variability

- C.
Giving the mean number of crimes committed by a demographic but not the variability

- D.
All of the above

- 18.___________ is the measure of variability most affected by outlier scores.
- A.
Range

- B.
Interquartile range

- C.
Variance

- D.
Standard deviation

- 19.When calculating variance for a sample, we use the following formula:Sum of Squares / (N-1)What benefit is there to subtracting 1?
- A.
Makes sure studies cannot be done with case studies (N=1)

- B.
The lower the number of participants, the more the -1 increases sample variability

- C.
If we don't subtract 1, the sum of deviations won't equal 0

- D.
Subtracting 1 makes the distribution appear more normal like

- 20.Why do we use standard deviation instead of variance?
- A.
Standard deviation takes into account the N of the sample

- B.
Standard deviation is less susceptible to outlier scores than the variance.

- C.
Standard deviation has the same scale of measurement as the mean

- D.
Standard deviation takes into account degrees of freedom of the sample

- 21.Which of the following is not a requirement of a perfect normal distribution?
- A.
Identical mean, median, and mode

- B.
Asymptotic distribution

- C.
Has a standard deviation of 1.

- D.
Has range of negative infinity to positive infinity

- 22.
- A.
Standard deviation = 1

- B.
Mean = 0

- C.
Easier to compare values across variables

- D.
Converting scores to a standard normal distribution turns the distribution into a perfect normal distribution

- 23.If I were to look at the scores on a test from a single classroom and assume the findings apply to the whole school, I would be using ___________.
- A.
Descriptive statistics

- B.
Inferential statistics

- C.
Sample statistics

- D.
Population statistics

- 24.Which of the following is true?
- A.
All consistent estimators are unbiased estimators

- B.
All unbiased estimators are consistent estimators

- C.
Not all biased estimators are consistent estimators

- D.
Consistent estimators are never biased estimators

- 25.Which of these is the crappiest type of sampling?
- A.
Snowball sampling

- B.
Convenience sampling

- C.
Random sampling

- D.
Stratified random sampling

- 26.Why isn't random sampling as good as stratified random sampling?
- A.
Random sampling does not give everyone an equal chance of participation

- B.
Random sampling is not independent

- C.
In random sampling you run the risk of asking both the old grandma at the grocery store as well as the grandpa she's with

- D.
Random sampling doesn't guarantee representativeness

- 27.The sampling distribution of a normally distributed variable with N = infinity would be...
- A.
Mezokurtic

- B.
Platykurtic

- C.
Leptokurtic

- D.
Random

- 28.The Law of Large Numbers states ___________.
- A.
Point estimators become increasingly less stable at large numbers

- B.
The larger the sample you take, the more likely you are to come close to the population mean

- C.
A sample is normally distributed when adding more people won't bring you any closer to the mean

- D.
Central limit theorom does not apply to significantly high values of Z

- 29.What is the estimated standard error of the mean?
- A.
The average distance away a score is from the mean

- B.
The average distance away a sample mean is from the population mean

- C.
The square root of the population variance

- D.
The likelihood that the sample mean is within 1 standard deviation of the population mean

- 30.Why might a WISC administrator not refer to an IQ of 89 as below average?
- A.
Because the FSIQ is an imperfect point estimator and therefore we really have no idea what the real score is

- B.
Because the FSIQ has not been found to be statistically valid or reliable

- C.
Because 42% of children score below 89 so it's really not that far below average

- D.
Because the 95% confidence interval falls between 88-96 so we're not all that certain the score is really below average

- 31.If I tell you that you got a Z score of -2 on the WAIS, you should feel:
- A.
Alarmed

- B.
Average

- C.
Appropriately proud

- D.
Incredibly proud

- 32.Which of the following is false about H0 and H1:
- A.
They must be mutually exclusive

- B.
They must be appropriate for the rejection criteria

- C.
There can be no overlap or exceptions

- D.
They must be all encompassing

- 33.I'm running some screening tests to see which kids should be monitored more closely next year because the screening test indicates they're at risk for learning disorders. What might I set my alpha to?
- A.
.005

- B.
.10

- C.
.95

- D.
.995

- 34.I'm writing software for missile-detection radar, to alert the Pentagon in case the Commies try to nuke us. What should I set my alpha to?
- A.
.005

- B.
.10

- C.
.95

- D.
.995

- 35.__________ is when you accept the null hypothesis when it's false.
- A.
Type 1 Error

- B.
Type 2 Error

- C.
H0 Error

- D.
H1 Error

- 36.__________ is used when you have a sample mean, estimated standard error, population mean, and N.
- A.
Independent samples t-test

- B.
Repeated measures t-test

- C.
One sample t-test

- D.
Bivariate t-test

- 37.__________ is used when you have two sample means, two estimated standard errors, and two Ns.
- A.
Independent samples t-test

- B.
Repeated measures t-test

- C.
One sample t-test

- D.
Bivariate t-test

- 38._________ is used when you compare two sample means from one population.
- A.
Independent samples t-test

- B.
Repeated measures t-test

- C.
One sample t-test

- D.
Bivariate t-test

- 39.If I'm doing a t-test and my N = 30 and I want to use 95% confidence, I should look up the t-table value at:
- A.
29 and .05

- B.
29 and .95

- C.
30 and .05

- D.
30 and .95

- 40.If I'm doing a t-test and my N = 32, I should look up the t-table value at:
- A.
30

- B.
40

- C.
Average 30 and 40

- D.
Average 30 and 40 with 80% weight on the 30

- 41.Independent samples t-test requires assuming all of the following except:
- A.
Each subject is randomly and independently selected from the population

- B.
Measurement is done on ratio variables

- C.
Assumption of homogeneity of variance

- D.
Scores in population form normal curve

- 42.Repeated measures t-test eliminates one of the assumptions from independent samples t-test, which?
- A.
Each subject is randomly and independently selected from the population

- B.
Measurement is done on ratio variables

- C.
Assumption of homogeneity of variance

- D.
Scores in population form normal curve

- 43.Say I test the effect of milk consumption on height by monitoring the height of students in a classroom where milk is supplied daily and the height of students in a classroom where milk is not supplied daily. I'm going through the steps to make a study and set my rejection parameters to t=2.045 with an alpha of .05. After I run my analysis, I discover that my independent samples t-test has returned me t=1.940. What conclusion should I reach, and what error am I at risk of committing?
- A.
Accept null hypothesis; Type 1 Error

- B.
Accept null hypothesis; Type 2 Error

- C.
Reject null hypothesis; Type 1 Error

- D.
Reject null hypothesis; Type 2 Error

- 44.Say I test the effect of milk consumption on height by monitoring the height of students in a classroom where milk is supplied daily and the height of students in a classroom where milk is not supplied daily. I'm going through the steps to make a study and set my rejection parameters to t=2.045 with an alpha of .05. After I run my analysis, I discover that my independent samples t-test has returned me t=1.940. I accept the null hypothesis, therefore, what is my conclusion?
- A.
With an alpha of .05, milk consumption over the course of a year does not alter students' heights

- B.
With an alpha of .05, milk consumption over the course of a year does alter students' heights

- C.
With an alpha of .05, this study was inconclusive and it is unclear what effect milk consumption over the course of a year has on students' heights

- D.
If the t-test returned 1.940, it is an indication that the N was too low and the study should be redone