UNIT CODE DED 1204 UNIT TITLE INTRODUCTION TO SOCIAL STATISTICS Explain clearly and using relevant examples the scales of measurementMeasurement is the assigning of numbers to objects according to a set of rules.

Interval scaleThis scale deals with differences between objects. In marketing it measures attitudes, opinions and index. In permissible statistics it range, mean and standard. The best example is the Fahrenheit scale for temperature. Ratio scaleIn ratio scale zero point is fixed, ratios of scale values can be compared. An example is weight or height.

Nominal scale This scale deals with classifying objects and identifying numbers. Nominal scale are qualitative, the main statistic used is percentages and mode. Examples of nominal scale are social security numbers and numbering games players. Ordinal scaleThis scale categorizes and rank orders items. It does not contain equal interval. An example is rating scales and rank orders. Explain the following methods of data collection Case studiesCase study refers to a process or a record of research into the development of a single unit such as a person, group or situation over a long period of time. Diaries A diary is a book showing information gathered on how individuals spend their time on professional activities.

It can record both qualitative and quantitative data Critical incidentsA critical incident is any actual or alleged situation or event that creates a significant risk of serious harm to the mental or physical health, safety of a researcher. PortfoliosThis is a grouping of financial assets such as bonds, cash and stocks equivalents as well as their funds and counterparts. In 1995 five firm registered the following economic growth rates 26% , 32%, 41%, 18% and 36%Work out Arithmetic mean Geometric mean Harmonic mean Arithmetic mean (Sum of all values)/(Total number of values) (26+32+41+18+36)/5 = 153/5 AM = 30.6% Geometric mean ?(3&a×b×c) ?(26×32×41×18×36) = ?22104576 GM =280.6472 Harmonic meanHM = n/(1/x1+1/x2+1/x3+?1/x6) =n/(?_i^(n=)??1 1/xi?) 1/26+ 1/32+ 1/41+ 1/18 + 1/36 =0.0385+0.0313+0.0244+0.

0556+0.0278 =0.1776 5/0.1776 HM =28.

1532 A sample comprises of the following observations 14, 18, 17, 16, 25, 31. Determine the standard deviation of this sample Standard deviationX x^214 19618 32417 28916 25625 62531 961_________________ ??x ?_x?2 121 2651 (( ? ?x)?^2)/n = 121×121 6 = 14641 6 =2440.1667 ?_x?2 __ (( ? ?x)?^2)/n = 2651_2440.1667 =210.8333 (210.

8333)/(n-1) = (210.8333)/(6-1) =(210.8333)/5 =42.1667Standard deviation = ?(2&42.1667) = 6.4936 5.

The following table shows the part time per hour of a given number of laborers in the month of June 1997 Rate per hour (x) No of labourers Shs (x) f 230 7400 6350 2450 1200 8150 11 ______ Total 35Work out Coefficient of variation Coefficient of skewness Coefficient of variationx f fx ? x?^2 fx^2230 7 1610 52900 370300400 6 2400 160000 960000350 2 700 122500 245000450 1 450 202500 20500200 8 1600 40000 3200001780 35 8410 600,400 2345300S.D = ((?f)???(fx^2 )-???( fx)2??)/((?f) (?f-1) ((35)(2345300)-(?8410)?^2)/(35 (35-1)) (82085500 -70728100)/(35×34) 11357400/1190S.D = 9544.0336Mean = (?fx)/(?f) = 8410/35Mean = 240.2857 Coefficient of variation =(standard deviation)/mean×100 Coefficient of variation =?/µ×100 9544.

0336/240.2857 =39. 7195 × 100 CV = 3971.7195