Category: Quantitative Methods / Explanation
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Augmented Dickey-Fuller (ADF) Test
Time Series and Stationarity: Time series in statistics is a series of data points ndexed in time order. Most commonly, these data points are considered at successive equally spaced points in time. Thus, we obtain then a sequence of discrete time data. Examples of time series are daily measures of fever, yearly counts of an epidemic in a…
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White Neural Network Test
Scope: Check for neglected nonlinearity in time series data or regression models. Consequences of non-linearity when linear approaches are used: Biased estimates, poor predictions and inaccurate understanding of the relationships between variables. In all cases, misleading conclusions can be derived, while non-linear models have to be considered. H0: Linearity in “mean” * Decisions before the…
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Presentation Of Statistical Data – Graphical Analysis
DOT DIAGRAMS IT IS THE PLACEMENT OF THE AVAILABLE PRICES IN A LINEAR SECTION * IT IS SUITABLE FOR A SMALL NUMBER OF OBSERVATIONS SOME OBSERVATIONS • THE AVERAGE CONSUMPTION PER GALLON OF GASOLINE IS VERY CLOSE FOR THE 3 CARS • THE VARIABILITY OF GASOLINE CONSUMPTION IN CAR 3 IS SMALLER TOO MANY VALUES…
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Presentation of Statistical Data 2
CONSTRUCTION OF FREQUENCY DISTRIBUTIONS – EXAMPLE: WEIGHT OF STUDENTS IN A FOURTH-GRADE 55, 51, 57, 63, 64, 55, 66, 70, 65, 62, 72.3, 51.5, 60.7, 52.3, 53.1, 54.7, 65.2, 62.7, 60.8, 55.2, 55.4, 57.7, 58.1, 60.4, 65. CLASS=6 (STURGESS TYPE=5.41022) CLASS WIDTH=3.6 The graph of a grouped distribution is made with the Histogram. FREQUENCY POLYGON…
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Hurst Exponent
Time series in statistics is a series of data points indexed in time order. Most commonly, these data points are considered at successive equally spaced points in time. Thus, we obtain then a sequence of discrete-time data. Examples of time series are daily measures of fever, yearly counts of an epidemic in a country, and the daily closing value of…
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Presentation of Statistical Data1
The most common way of presenting data is:FREQUENCY DISTRIBUTIONS AND HISTOGRAMS TERMINOLOGYFREQUENCY: The number of data in a class.RELATIVE FREQUENCY: The percentage of all data values that are in a class.HISTOGRAM: The graphical presentation of (relative) frequencies FREQUENCY DISTRIBUTION: CONSTRUCTION KEY POINTS IN CONSTRUCTING FREQUENCY DISTRIBUTIONS Note: Grouping data leads to loss of information. The…
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Data Types – Sources of Statistical Information – Research Types
DATA TYPES QUANTITATIVE: NUMERICAL OBSERVATIONS RESULTING FROM MEASUREMENT (e.g. Weight, Height, Age, Salaries, Stock Market Prices, Number of Products) QUALITATIVE: CATEGORIC OBSERVATIONS (NON-NUMERICAL) RESULTING FROM A SURVEY QUESTION (e.g. Gender (Male, Female), Marital Status (Married, Single), Type of Housing (Detached House, Apartment Building), Educational Level (First Degree, Second Degree, Third Degree) COMMENTS ON QUALITATIVE DATA:…
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Basic reason for using statistics – descriptive statistics
In many fields and many sciences, e.g. physics, biology, medicine, economics, etc., it is necessary to collect and analyze data concerning a set of objects in order to draw conclusions about it. Descriptive statistics: deals with the concise and effective presentation of the data of a statistical survey. (the other broad category is the inferential…
Quantitative Data Analysis 