Term
What are those two groups that Biostats is divided in? 

Definition
1. Descriptive 2. Inferential 


Term
What are the measures of central tendency? 

Definition
The Mean, The Median and The Mode 


Term
It is the most frequently value occurring in a dataset: A. Median B. Mean C. Mode 

Definition


Term
What is called the middle value in a ordered list of values from the smallest to the largest? A. Mean B. Mode c. Median 

Definition


Term
Inferential statistics allows to make general assumptions about a population. TRUE or FALSE? 

Definition
True: with Inferential Biostatistics you take data from samples of objects from a population and make generalizations about a larger population of subjects. 


Term
Inferential Biostatistics are NOT good for comparing treatment drugs. TRUE or FALSE? 

Definition
FALSE: Inferential Biostatistics are used to compare differences between treatment groups. 


Term
Significancy of a sample are composed by the characteristics of a sample that best describe a population. TRUE or FALSE? 

Definition
TRUE: it is essential that the sample is significative to accurately predict the population. 


Term
What does the Gaussian Curve show? 

Definition


Term
When we say that a probability distribution is symmetric about the mean we are referring to: 

Definition
NORMAL DISTRIBUTION or GAUSSIAN CURVE (Bell curve) 


Term
The Central Limit Theorem states that if you have a population with a MEAN and a STANDARD DEVIATION and take suffiCIently large samples from the population WITH REPLACEMENT, then the distribution of the SAMPLE MEAN will be approximately normally distributed. TRUE or FALSE? 

Definition


Term
What is the proportion of a population/sample between the MEAN and a +1SD? 

Definition


Term
In a normal distribution, a percentile 50 matches with: A. MEAN B. MEDIAN C. BOTH D. NONE 

Definition
"C: BOTH" In a normal distribution, the mean, median, and mode all have a corresponding zscore of 0 and are the 50th percentile. 


Term
in an asymmetrical distribution, where is the tail located when is positive skewed? 

Definition


Term
Starting from left to right, what is the other of the central tendency measurements when it is a negative skewed distribution? 

Definition
From left to right: MEAN , MEDIAN and MODE 


Term
What the order (from left to right) of the Median, Mode and Mean when the values al positive skewed? 

Definition
MODE, then MEDIAN and finally the MEAN 


Term
What's the lowest value in a positive skewed distribution? 

Definition


Term
What's the lowest value in a negative skewed distribution? 

Definition


Term
What is the hightest value in a positive skewed distribution? 

Definition


Term
What's best definition for the following: μ > M > Mode
a. Symetrical distribution b. Positive skewed c. Negative skewed 

Definition


Term
What is another name for Leptokurtosis? 

Definition


Term
In a distribution with positive Kurtosis: A) Heavier tails than normal distribution B) Weaker tails than normal distribution C) Same tails as normal distribution D) There are more values in the tails than in normal distribution E) A + D F) B + D G) NONE OF ABOVE 

Definition
"E" Positive Kurtosis has heavier tails and so more values in the tails than in a Normal Distribution 


Term
Leptokurstosis has more data in the tails than in the normal distribution: true or false 

Definition
TRUE: It has a heavier tail:more datas in the tails. This causes HIGH PEAKS. 


Term
Positive Kurtosis tend to have heavy outliers. When can you say it is a positive kurtosis? A. Kurtosis is =1 B. Kurtosis is < 3 c. Kurtosis is > 1 d. Kurtosis is > 3 e. Kurtosis is > 0 

Definition
D: Image result for pOSITIVE KURTOSIS HIGH PEAKS If the kurtosis is greater than 3, then the dataset has heavier tails than a normal distribution (more in the tails). 


Term
How do you interpretate when a Kurtosis value is less than 3? 

Definition
That the dataset has lighter tails thus the it is normally distributed. 


Term

Definition


Term
How do you call when you have a dataseet with an excess of extreme values and so your distribution is flatter than the normal distribution? 

Definition


Term
What type of variable is the Blood Type? A. NOMINAL B. ORDINAL C. CONTINIOUS 

Definition


Term
ORAL HYGIENE INDEX is a a variable type: 1. Discrete 2. NOMINAL 3. ORDINAL 

Definition


Term
AGE is a variable type: A. Ordinal B. Nominal C. Continuos D. Discrete 

Definition
A/B : age could be both nominal or ordinal 


Term
Satisfaction Level is a variable type: A. Ordinal B. Nominal C. Continuos 

Definition


Term
Years of Education is a variable type: A. Ordinal B. Nominal c. continuos 

Definition


Term
In count or discrete variable: there is no decimal numbers (1.15, 2.50, etc) ¿TRUE OR FALSE? 

Definition
TRUE: only whole numbers are included, starting from 0 to INFINITE. 


Term
Number of cavities in an oral cavity: A) NOMINAL B) CONTINUOS C) ORDINAL D) NONE OF ABOVE 

Definition
D) NONE OF ABOVE: The answer is DISCRETE because you count cavities from 0 


Term
LEVELS of CHOLESTEROL in BLOOD: A) Nominal B) Discrete C) Continuos D) Ordinal 

Definition
C) CONTINUOS (if it has numbers) or D) (if you clasify them as high  medium  low) 


Term
A Parameter is associated with: A) SAMPLE B) POPULATION 

Definition


Term
A Statistic is associated with: A) SAMPLE B) POPULATION 

Definition


Term
Write the Normal Distribution equation 

Definition


Term
Write the STANDARD NORMAL DISTRIBUTION equation 

Definition


Term
Write the formula of how to find µ 

Definition


Term
Write the formula of σ (Population Standard Deviation) 

Definition


Term
Write the formula to find "Z" 

Definition


Term
What is the formula to find the Median? 

Definition
Median = N + 1 / 2 . The result is the order of the value arranged in increasing order. 


Term
Write the formula to find the variance in POPULATION and in SAMPLE. 

Definition


Term
Write three symbols of population parameters and tell if they all are measured in the same units. 

Definition


Term
A numerical measure computed from a sample, such as sample mean, is known as a
a.population parameter
b.sample parameter
c.sample statistic
d.population mean 

Definition


Term
A numerical measure, such as a mean, computed from a population is known as a
a.population parameter
b.sample parameter
c.sample statistic
d.sample mean 

Definition


Term
Which of the following descriptive statistics is not measured in the same units as the data?
a.35th percentile
b.standard deviation
c.variance
d.interquartile range 

Definition


Term
How do you obtain the sample to obtain external validity? 

Definition


Term
What are the two properties that sample size influences on? 

Definition
1. The power of the study to draw conclusions
2. The precisions of the estimates 


Term
What does random sampling ensure? 

Definition
Random sampling ensures external validity . Less bias. 


Term
The sample mean is an unbiased estimator of the population mean. TRUE or FALSE 

Definition


Term
The sample range is an unbiased estimator of the population range. TRUE OR FALSE? 

Definition
FALSE: Range is ALWAYS BIASED 


Term
If I have a dataset of 7 values, how do I find the median? 

Definition
7+1 / 2 = THE FOURTH VALUE of the data set is the median. 


Term
The estimated precision of the sample mean increases with ___________ 

Definition


Term
CAN YOU CALCULATE THE GEOMETRIC MEAN WHEN AN OBSERVATION INCLUDES 0 (ZERO)? 

Definition
NO: You can only calculate geometric mean when the values of the observations are greater than zero. 


Term
When are the geometric and arithmetic mean the same? 

Definition
They will only be equal when the variance is ZERO. 


Term
What do you use to remove positive skew? 

Definition


Term
What happens to the geometric mean when you use LOG TRANSFORMATION DATA to remove positive skewness? 

Definition
The gemoetric mean INCREASES. 


Term
Is random sampling sufficient to ensure external validity? 

Definition
NO: Because some subjects may decline to participate 


Term
Name 4 SAMPLE MEASURES of spread (dispersion) 

Definition
1. Standard Deviation 2. Variance 3. Ranges 4. Interquartile ranges 


Term
When do you use the geometric mean? 

Definition
When the data values are expressed in RATIOS or in PERCENTAGES 


Term
The sample variance is unbiased: TRUE or FALSE? 

Definition


Term
How do you calculate a QUARTILE when n is ODD? 

Definition


Term
How to calculate q quartile range when n is even? 

Definition


Term
What's the equation to find a MEDIA? 

Definition

