Assiment thursday Flashcards
What are P-Values
An equation to findout what’s the probability of the theorized question. P can take any value between 0 and 1. The closer equation to 1 is most more probable then an equation to 0
What is a T test: Paired Two Sample for Means
Usallally used to mesure somthing in time eg before and after eg wieght before the diet and weght after. Measures two dependent samples and measure wither or not they signifigently differ from each means
What is a T test Two-Sample Equal Variances
Used when both variances are the same eg taking a sample size of two population and figureing out if they are the same ( Look at the p value)
What is Regression
Regression anaylisis is a satistical method that mesures the relationship between two or more variables of interest. Often it is shown in a graph with a line (the reggression line) to show the patten. or Regression is trying to find out which one affects Y the most
What is Correlation
Used to uderstand the relationship between variables
What are Descriptive Statistics
a set of methods used to summarize and describe the main features of a dataset
The mean, the mode, the median, the range
What is ANOVA Single Factor
Analysis of variance or ANOVA can be used to compare the means between two or more groups of values.
Using the P values what percentage is more likley to be probable 0.05 or 0.5
0.5
What is the independent variable
X
What is the dependent varable
Y
If the question was : what contribes to test score with other verables being, attendance, socail media, and learning at home what would be the test score be X or Y
Y becouse it is the dependent varble
Using the T statistics and the P t statstics is there signifcigent differences between 0.95 & 0.45
No there is not a significant differences because both percentages don’t go under 0.05. The P value is great then 0.05
How do you mesure the corrlation between varables
using a mesuring stytem eg -1 = not strong corrlation 0= medium corrlation 1= strong corrlation
In a graph does a posative corrlation go up or down
UP
In a graph does negative correlation go up or down
down
Can you still have a strong correlation if the correlation is a negative
yes becouse there is still a strong pattern
When is the corrlation not strong ?
When the data is spread out and a pattern is not clear eg 0.3 correlation will not show a strong pattern compared to 0.7
What does Statistically significant mean
Statistically significant is how you measure how its important or true it is to the variable effect. Eg Pirates and summer days may both see an in incress but they are not statistically significant
where do we look in the regression stats to
to find out the
if its Significantly significant
ANOVA
where do we look in the regression stats to
to find out the significance for each variable.
Coefficients intercepts
where do we look at the graph if we want to out if the model fits ?
(Looking in the reggresion graft)
regression statistics
Always use BEDMAS in eqshions, what does bedmas stand for?
Brackets, Exponents, Division/Multiplication, Addition/Subtraction
Work out this equation
Sales = 5,95(advertspent) +70000
Every Unit you put into advertising spend you get an increase of 5.95 everytime. How much money would you get if you spent 1000
12950
Im guessing
But i think the caculation should look like this
5.95 x 1000 + 7000
Sales=advertising spend+ c
Work out this eqaustion
Sales = 5,95(advertspent) +70000
Every Unit you put into advertising spend you get an increase of 5.95 everytime. You currently have an revanue of 555,000 how much money did you put into advertsing
555,000/5.95=93277.31- 7000 = 86277.31
revaune/advertsing spending-C(7000) = cost of advertsing ??
Confused
what does each of these mean
The mean,
the mode,
the median,
the range
Mean is the average of all of the numbers. Median is the middle number, when in order. Mode is the most common number. Range is the largest number minus the smallest number.
Uses of Regression ?
forecasting an effect and is used to predict the impact or impact of changes. This is used to understand how much the dependent variable changes with the evolution of the independent variable.eg, how much sales are increased with extra $1000 spent on marketing?
