1 Pertemuan Kesembilan Sampling and Data Collection Matakuliah: MN J0412/ Riset Pemasaran Tahun: 2007 Versi:

2 Learning Outcomes Pada akhir pertemuan ini, diharapkan mahasiswa akan mampu : Mahasiswa dapat menyisihkan sampel dan populasi tanpa menghilangkan unsur

3 Outline Materi Materi 1: Required Steps in Sampling Materi 2: Types of Sampling Plans Materi 3: Non Probability Samples Materi 4:Probability Samples Materi 5: Sample Size

4 6-Step Procedure for Drawing a Sample Define the Target Population Identify the Sampling Frame Select a Sampling Procedure Determine the Sample Size Select the Sample Elements Collect the Data from the Designated Elements Step 1 Step 2 Step 4 Step 3 Step 5 Step 6

5 Classification of Sampling Techniques Sampling Designs Nonprobability Samples Convenience Judgment Quota Probability Samples Simple Random Statified Proportionate Disproportionate Cluster Systematic Area

6 Distribution of Sample Means for Different Samples Sizes, Population Shapes n = 2 Populations n = 5 Sampling Distributions of mean n = 30

7 Relationship Between Parameters of Parent Population and Derived Population ABCDEFABCDEF ElementTotal Parent Population Mean:   X i N Variance:  2   (X i -  ) 2 (3-10.5) ( ) 2 N 6 = = = = = = = 10.5

8 Derived Population of All Possible Distinguishable Samples ABC ABD ABE ABF ACD ACE ACF ADE ADF AEF BCD BCE BCF BDE BDF BEF CDE CDF CEF DEF ElementTotalMean X j

9 Derived Population Mean: =( ) 2 + (7-10.5) ( ) 2 20 Variance:  2  = 5.25 E( x )  x L  x j j =1 L L  ( x j j =1 L - E(x)) 2 20 == = = 10.5 = _x_x

10 Distribution of Variables in Parent and Derived Population Values of x Values of X Absolute Frequency Absolute Frequency

11 Example Calculations of Generating a Confidence Interval with a Stratified Sample III IIIIV n 1 = 100 x 1 =  X i1 = 3.2 n1n1 x 1 ) 2  (X i1 =.14 n1n1 s 1 2 = ^ n 3 = 100 x 3 =  X i3 = 5.8 n3n3 x 3 ) 2  (X i3 =.20 n3n3 s 3 2 = ^ n 4 = 100 x 4 =  X i4 = 7.2 n4n4 x 4 ) 2  (X i4 =.18 n4n4 s 4 2 = ^ n 2 = 100 x 2 =  X i2 = 4.6 n2n2 x 2 ) 2  (X i2 =.12 n2n2 s 2 2 = ^

12 Size and Strata in Parent Population N 1 = N 2 = N 3 = N 4 = N = x st = = 1/10(3.2) + 5/10(4.6) + 3/10(5.8) + 1/10(7.2) = 5.08 = (1/10) 2 (.14) + (5/10) 2 (.12) + (3/10) 2 (.20) (1/10) 2 (.18) = =.0226 NhxhNhxh N  L h=1 WhxhWhxh  L s x st =  L h=1 Whs2xhWhs2xh = NhNh N 2 (s h ) 2 nhnh ^  L h=1 2 s x st = I. II. III. IV ()