• Their principal use is twofold: 1. Within organizations, the collection, analysis g , , y and dissemination of these data ensuring that they have a positive experience with y p p the company’s goods and services services. 2. 2 Although sales or market share can indicate how well a firm is performing currently, satisfaction is an indicator of how many customers will make further purchases in the future future.
• There are various ways to obtain customer g feedback with regard to their satisfaction levels with the product(s) and the company. Some of them are, company Some of them are – Telephone follow‐up Telephone follow‐ – Customer complaint data Customer complaint d l data – Direct customer visits Direct customer visits – Customer advisory councils Customer advisory councils – User conferences User conferences
• Th There are ththree common methods t gather survey th d to th data: face‐to‐face interviews, telephone interviews, and mailed questionnaires.• The personal interview method requires the interviewer to ask questions based on a pre‐structured pre‐ questionnaire and to record the answers answers.• Telephone interviews are less expensive than face‐to‐ face interviews. These can be monitored by the research t h team t ensure th t th specified i t i to that the ifi d interview procedure is followed.• The mailed questionnaire is less expensive However, expensive. this savings is usually at the expense of response rates rates.
Face‐to‐Face Telephone Interview Telephone Interview Mailed Mailed Interview Questionnaire Gives very high Less expensive and special Very Lessdegree of validity methods needed to increase Expensive butof the data efficiency. more chances for low response p rate.The major The limitations of this Questionnairelimitations are method are the lack of direct developmentcosts and factors observation, the lack of using requiresconcerning the exhibits for explanation, and professionalinterviewer.i i the li i d group of potential h limited f i l knowledge and k l d d respondents—those who can experience and be reached by telephone. should be dealt with accordingly.
Survey se Rate ations Length of bility view pling bits dity ed st Spee ype of S Observa Exhib Cos Valid Interv Flexib espons Samp Re O TyIn Person – – + – + – + – ++ ++ + + ++Phone + + ++ + + – – – +Mail ++ – –– – – – + + +– – – = Disadvantage – – = Worst g + = Advantage ++ = Best + – = Could be an Advantage or a Disadvantage
• Wh th customer b When the t base i l is large it i t costly t large, is too tl to survey all customers. customers• Estimating the satisfaction level of the entire customer population through a representative sample is more efficient efficient.• To do that Scientific probability sampling methods are used.• There are four basic types of probability sampling sampling: – Simple Random Sampling – Systematic Sampling – Stratified Sampling – Cluster Sampling. Sampling.
• I systematic sampling one simply goes d In t ti li i l down a list taking every kth individual, starting with a randomly selected case among the first k y g f individuals.• Systematic sampling is simpler than random sampling if a li t i extremely l li list is t l long or a l large sample is to be drawn.• However there are two types of situations in However, which systematic sampling may introduce biases: – (1) The entries on the list may have been ordered so that a trend occurs and – (2) the list may possess some cyclical characteristic that coincides with the k value.
• I In a stratified sample, we first t tifi d l fi t , and . • The strata are usually based on important variables pertaining to the parameter of interest. t i i t th t fi t t• Stratified sampling, when properly designed, is more efficient than simple random sampling and more efficient than simple random sampling and systematic sampling.• Stratified samples can be designed to yield greater p g y g accuracy for the same cost, or for the same accuracy with less cost.
• I t tifi d In stratified sampling we sample within each li l ithi h stratum. Sometimes it is advantageous to divide the . • A cluster sample is a simple random sample in which each sampling unit is a cluster of elements. hi h h li it i l t f l t• Usually geographical units such as .• Cluster sampling is generally less efficient than p g g y simple random sampling, but it is .
• H l How large a sample i sufficient? l is ffi i t?• The answer to this question and .• The higher the level of confidence we want from the sample estimate, and the smaller the error margin, , and vice versa. versa• For each probability sampling method, , some of which (such as that for cluster sampling) are quite complicated.
• The following formula is for (e.g., percent satisfied) based on on : NZ × p(1 − p ) 2 n= NB 2 + [ Z 2 × p (1 − p)] N – Population Size for 80% Confidence Level, Z = 1.28 Z – Z Statistic from normal distribution for 85% Confidence Level, Z = 1.45 P – Estimated Satisfaction Level for 90% Confidence Level, Z = 1.65 B – Margin of Error for 95% Confidence Level, Z = 1.96
• The five‐point satisfaction scale ( h fi i if i l (very satisfied, satisfied, neutral, dissatisfied, and very dissatisfied) is often used in customer satisfaction surveys. • The data are usually summarized in terms p of percent satisfied. • In presentation, run charts or bar charts to show the trend of percent satisfied are show the trend of percent satisfied are often used.