Correlation between Media Variables and Birth Rate

Abstract

The study purpose was to use the technique of cross-lagged correlation to investigate the following hypothesis: media development with regard to newspapers television radio and cinema has more of an influence on birth rate than birth rate has on media development. The expected influence should be negative with increases in the mass media variables leading to decreases in birth rate. Data were taken from U.N. Statistical Yearbooks for 1955 1965 and 1975. The 3 time points were chosen somewhat arbitrarily but in the belief that at least 10 years would be necessary for changes in the mass media to have an impact on birth rate. Data from 76 countries were gathered for the following variables: daily newspapers/1000 population television receivers/1000 population radio receivers/1000 population annual per capita cinema attendance and crude birth rate. In addition data were gathered for the following variables to be used as possible control variables: literacy rate education employment and per capita annual income. 12 different cross-lagged correlations described the relationships between birth rate and each mass media index with all 4 of these examined for 1955 versus 1965 1965 versus 1975 and 1955 versus 1975. Only 7 of the 12 cross-lagged correlations show a difference in the direction that would support the hypothesis and in most of these the difference is statistically significant when tested by the Pearson-Filon formula for cross-lagged correlations i.e. the relationship between radio and birth rate for 1955 versus 1965. The difference indicates that radio in 1955 is influencing birth rate in 1965 more than birth rate in 1955 is influencing radio in 1965. When zero order correlations between birth rate and the 4 media variables for each of the 3 years were analyzed there were significant negative correlations between media variables and birth rate for only 6 of the 12 instances examined. Newspapers had the predicted relationship with birth rate in 1955 and 1965 but not in 1975. Television did not have the predicted relationship with birth rate for any of the 3 years. Radio had the predicted relationship with birth rate in 1955 and 1975 but not in 1965. Cinema had the predicted relationship with birth rate in 1955 and 1965 but not in 1975. Introducing control variables by means of partial correlation found almost all of these relationships to be spurious.