Before we can understand the present state of the psychology of religion – with its frequent emphasis on empirical data – it can be helpful to understand the field’s history. The prominent theoreticians that we explore in this chapter – James, Freud, Jung, Maslow, Fromm, Allport, Becker, Frankl, and others – remain influential in the twenty-first century, but they are also controversial. William James’ biography and writings show that debates about religion were never purely intellectual matters for the great scientist and philosopher. Freud’s theorizing on religion is discussed in detail, including his ideas on the origin and meaning of mystical religious experiences, the roots of theistic belief in wish-fulfillment, the notion of religion as a universal obsessional neurosis, and the assessment of the historical importance of religion for civilization. This discussion of Freud is followed by consideration of Carl Jung’s more sympathetic outlook on aspects of religion. The chapter concludes with a comprehensive discussion of the many ways humanistic and existential thinkers have studied religion and spirituality.

Intersymbol interference (ISI) occurs for linear dispersive channels (i.e., channels where the transfer function is not flat within the transmission band). Hence, an obvious strategy to avoid ISI is to divide the transmission band into a large number of subbands, which are used individually in parallel. If these bands are small enough, such fluctuations of the channel transfer function can be ignored and no linear distortions occur that would have to be equalized. In this chapter, we study this idea in the particular form of orthogonal frequency-division multiplexing (OFDM). It is shown that even starting from the frequency-division multiplexing idea, the key principle behind OFDM is blockwise transmission and the use of suitable transformations at transmitter and receiver. We analyze OFDM in detail and show how the resulting parallel data transmission can be used in an optimum way. OFDM is compared with the equalization schemes discussed in the previous chapter, and incorporated in the unified description framework.

This chapter presents a discussion of the nature of psychological tests, how they are constructed, and how clinical psychologists use them. It shows that most psychological tests can be categorized as measuring (a) intellectual abilities; (b) attitudes, interests, and values; or (c) aspects of personality, including psychopathology. Tests can also be categorized according to the kinds of responses requested – some ask for brief, easily scored responses (such as true or false), whereas others require longer, more difficult-to-score responses (such as stories or drawings). The chapter presents descriptions of the tests that are most commonly used by clinicians. It also provides information about the tests’ psychometric properties, including how their designers seek to avoid bias when the instruments are used with diverse client populations. It also discusses these tests’ clinical utility. The chapter concludes with a summary of recent developments in psychological testing.