STATS MT Flashcards
calculation of probabilities of a population to make prediction and decisions
STATISTICS
what does continuous type of data requires
NORMAL PROBABILITY DISTRIBUTION
a probability distribution of continuous random variables
NORMAL PROBABILITY DISTRIBUTION
what is the shape of distribution curve
BELL
where is the relation of curve and center
SYMMETRICAL
what coincide at the center
MEAN MEDIAN MODE
what flatten out indefinitely along the horizontal axis but never touch
TAILS OF THE CURVE
what is the area under the curve
ONE
2 factors that affect the normal curve
MEAN
STANDARD DEVIATION
shifts the graph of the normal curve to the right or to the left
CHANGE OF VALUE OF MEAN
what determines the shape of the graphs
STANDARD DEVIATION
when standard deviation is large?
NORMAL CURVE IS SHORT AND WIDE
when standard deviation is small?
NORMAL CURVE IS TALL AND SKINNIER
a normal probability distribution that has myu equals 0 and standard deviation equals to 1
STANDARD NORMAL CURVE
refers to 68-95-99.7 percent
EMPERICAL RULE
measure of relative standing
Z SCORE
number of standard deviation a given value x is above so below the mean
Z SCORE
distance between a given value x and to the mean
STANDARD SCORE
useful for comparing observed values
STANDARD SCORE
if one score is positive and one score is negative
ADD SCORES
if both score in same direction ( both left / both right )
SUBTRACT SCORES
positive scores going to the right
SUBTRACT 0.5
positive scores going to the left
ADD 0.5
negative scores going to the right
ADD 0.5
negative scores going to the left
SUBTRACT 05
cannot be negative
AREA
atleast
GOING TO THE RIGHT
at most
GOING TO THE LEFT
above
GOING TO THE RIGHT
below
GOING TO THE LEFT
to get z score
X MINUS µ over standard deviation
to get x
STANDARD DEVIATION TIMES Z PLUS µ
to get µ
X MINUS STANDARD DEVIATION TIMES Z
to get standard deviation
X MINUS µ OVER Z
indicates the score or the observed score is above the mean
POSITIVE Z SCORE
indicates the score or the observed score is below the mean
NEGATIVE Z SCORE
set of all possible values of a variable
POPULATION
consists of one or more data drawn from the population
SAMPLE
a sampling method of choosing representatives from the population wherein every sample has an equal chance of being selected
RANDOM SAMPLING
most basic random sampling wherein each eelemnt in the population has an equal probability of being selected
SIMPLE RANDOM SAMPLING
done by lisitng all the elements in the population and selecting every nth element in your population list
SYSTEMATIC RANDOM SAMPLING
population is divided into different strata or divisions
STRATIFIED RANDOM SAMPLING
wherein each population is divided into clusters or groups and then randomly sleected
CLUSTER SAMPLING
measurement of quantity that describes the population
PARAMETER
the measurement of quantity that describes the sample
STATISTIC
a frequency distribution using the means computed from all possible random sample
SAMPLING DISTRIBUTION OF SAMPLE MEANS
difference between the sample mean and the population
SAMPLING ERROR
